Engineering Project Management Civil Engineering Department.
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Transcript of Engineering Project Management Civil Engineering Department.
Engineering Project Management
Civil Engineering Department
2
An-Najah National University
Civil Engineering Department
Faculty of EngineeringConstruction Engineering
andManagement
Nabil Dmaidi
April 10, 2023
3
Your Expectations of MeBe preparedBe on time
Teach for full 50 minute period
Fair grading systemFront load the class workDo not humiliate students
Practice golden ruleProvide real world examples
Make you think
April 10, 2023
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Topics1) Management Functions and introduction of construction project planning and scheduling2)Construction scheduling techniques3)Preparation and usage of bar charts4)Preparation and usage of the Critical Path Method (CPM)5)Preparation and usage of Precedence Diagramming Method (PDM)6)Issues relating to determination of activity duration7)Contractual provisions relating to project schedules8)Resource leveling and constraining9)Time cost tradeoff10)Schedule monitoring and updating.11)Communicating schedule12) Project control and earned value Control13) claims, Safety and Quality control
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Course Outline
Introduction and definitions Float Analysis
Importance of Scheduling The CPM Calculations
Networks, Bar Charts, and Brief introduction on:
Imposed Finish Date and Project Control and Earned
Value Analysis Resource Allocation /Leveling other CPM Issues Time/Cost Trade-off
Precedence Networks
Updating Schedules
Time-Scaled Logic Diagrams
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In order to understand project management, one must begin with the definition of a projectproject. A project can be considered to be any series of activities and tasks that :.
● Have a specific objective to be completed within certain specifications
● Have defined start and end dates
● Have funding limits (if applicable)
● Consume human and nonhuman resources (i.e., money, people, equipment)
● Are multifunctional (i.e., cut across several functional lines)
What is the Project
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OR
‘‘a temporary endeavor undertaken to create a unique product, service, or result’’
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Project Life CycleApril 10, 2023
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Five Process group
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Successful project management can then be defined as having achieved the project objectivesproject objectives:
● Within Time
● Within Cost
● At the desired performance/Technology level
● While utilizing the assigned resources effectively and efficiently
● Accepted by the customer
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What is Project Management Project management is the planning, organizing,
directing, and controlling of company resources for a relatively short-term objective that has been established to complete specific goals and objectives.
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The potential benefits from project management are:
● Identification of functional responsibilities
● Minimizing the need for continuous reporting
● Identification of time limits for scheduling
● Identification of a methodology for trade-off analysis.
● Measurement of accomplishment against plans
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The above definition requires further comment. Classical management is usually considered to have five functions or principles:
● Planning
● Organizing
● Staffing
● Controlling
● Directing
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Planning
– Where the organization wants to be in the future and how to get there.
Organizing
– Follows planning and reflects how theorganization tries to accomplish the plan.
– Involves the assignment of tasks, grouping oftasks into departments, and allocation of resources.
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Leading
– The use of influence to motivate employees toachieve the organization's goals.
– Creating a shared culture and values,communicating goals to employees throughoutthe organization, and infusing employees toperform at a high level.Controlling
– Monitoring employees' activities, determining if the organization is on target toward its goals, and making corrections as necessary
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Conceptual Skill—the ability to see the organization as a whole and the relationship between its parts.
Human Skill—The ability to work with and through people.
Technical Skill—Mastery of specific functions and specialized knowledge
Management SkillsApril 10, 2023
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Project management is designed to manage or control company resources on a given activity, within time, within cost, and within performance. Time, cost, and performance are the constraints on the project.
Constraints of the project April 10, 2023
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Resources We have stated that the project manager must control company resources within time, cost, and performance. Most companies have six resources:
● Money
● Manpower
● Equipment
● Facilities
● Materials
● Information/technology
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Actually, the project manager does not control any of these resources directly, except perhaps money (i.e., the project budget).
Resources are controlled by the line line managersmanagers .
The project manager project manager is responsible for coordinating and integrating activities across multiple, functional lines. The integration activities performed by the project manager include:
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● Integrating the activities necessary to develop a project plan
● Integrating the activities necessary to execute the plan
● Integrating the activities necessary to make changes to the plan
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Project Scheduling Project Scheduling Planning, Scheduling, Planning, Scheduling,
and Controland Control
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Planning and Scheduling
Planning and scheduling are two terms that are often thought of as synonymous
They are not!
Scheduling is just one part of the planning effort.
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Project planning serves as a foundation for several
related functions such as cost estimating, scheduling,
and project control.
Project scheduling is the determination of the timing and sequence of operations in the project and their assembly to give the overall completion time
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Planning is the process of determining how a project will be undertaken. It answers the questions:
1“ .What” is going to be done,2“ .how,”
3“ .where,”4 .By “whom”, and
5“ .when” (in general terms: start and finish).
Scheduling deals with “when” on a detailed level… See Figure 1 .
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The Plan
WhatHow much
By whom
where
Why
How
when
Figure 1 . Planning and Scheduling
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The PlanPMI defines project management plan as a ‘‘formal, approved document that defines how the project is executed, monitored and controlled”.
The plan can include elements that has to do with scope, design and alternate designs, cost, time, finance, land, procurement, operations, etc.
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WHY SCHEDUALE PROJECTS ?
1 -To calculate the project completion.
2 -To calculate the start or end of a specific activity.
3-To expose and adjust conflict between
trades or subcontractor.
4 -To predict and calculate the cash flow.
5-To evaluate the effect of changing orders ‘CH . ’
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6 -To improve work efficiency.
7 -To resolve delay claims , this is important in critical path method ‘CPM’ discussed later..
8 -To serve as an effective project control tool.
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The Tripod of Good Scheduling System1.The Human Factor : A proficient scheduler
or scheduling team.
2. The Technology : A good scheduling computer system (software and hardware)
3. The Management : A dynamic, responsive, and supportive management.
If anyone of the above three ‘‘legs’’ is missing, the system will fail.
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Scheduling and project management Planning, scheduling, and project control are extremely important components of project management.project management includes other components :• cost estimating and management,
• procurement,
• project/contract administration,
• quality management,
• and safety management.
These components are all interrelated in different ways.
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Quiz 1True or False:
1.There are no two projects that are identical
2.Every construction project needs a CPM schedule
3.Planning and scheduling are two names for the same function
4.The maintenance of a large office building is considered a project
5.The renovation of a large office building is considered a project
6.There is one standard way to break down the project into activities for the purpose of creating a schedule
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Bar (Gantt) ChartsBar (Gantt) Charts
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DEFINITION AND INTRODUCTION
• A bar chart is ‘‘a graphic representation of project activities, shown in a time-scaled bar line with no links shown between activities’’
The bar may not indicate continuous work from the start of the activity until its end.
or
Non continuous (dashed) bars are sometimes used to distinguish between real work (solid line) and inactive periods (gaps between solid lines)
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• Before a bar chart can be constructed for a project, the project must be broken into smaller, usually homogeneous components, each of which is called an activity, or a task.
Item ActivityM 10 Mobilization
Bars ( Month or Year )
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ADVANTAGES OF BAR CHARTS
1- Time-scaled
2- Simple to prepare
3- Can be more effective and efficient if CPM based - Still the most popular method
4- Bars can be dashed to indicate work stoppage.
5- Can be loaded with other information (budget, man hours, resources, etc.)
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Bar Charts Loaded with More Info.Such as : budget, man hours and resources .
10 12 7 11 10 9 15
500$
220$
400$
850$
140$ 500$
900$
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DISADVANTAGES OF BAR CHARTS
1- Does not show logic
2- Not practical for projects with too many activities-As a remedy, we can use bar charts to show:
1. A small group of the activities (subset)
2. Summary schedules
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Quiz 2
True or False:1.The bar representing a 4-day activity is twice as long
as a bar representing a 2-day activity in a bar chart
2.Bar chart method lost its applicability with the introduction of the Critical Path Method
3.Bars in a bar chart must be connected with relationship lines
4.A bar representing an activity in a bar chart may not be continuous
5.Bar charts and Gantt charts are two different methods.
6.Bar charts can be loaded with information other than the timeline of the project
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Basic NetworksBasic NetworksApril 10, 2023
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DEFINITION AND INTRODUCTION
• A network is a logical and chronological graphic representation of the activities (and events) composing a project.
• Network diagrams are the preferred technique for showing activity sequencing.
• Two main formats are the arrow and precedence diagramming methods.
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Two classic formatsAOA: Activity on ArrowAON: Activity on Node
Each task labeled withIdentifier (usually a letter/code)Duration (in std. unit like days)
There are other variations of labeling
There is 1 start & 1 end event
Time goes from left to right
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Arrow Diagramming Method (ADM)
1 .Also called activity-on-arrow (AOA) network diagram or (I-J) method (because activities are defined by the form node, I, and the to node, J)
2 .Activities are represented by arrows.
3 .Nodes or circles are the starting and ending points of activities.
4 .Can only show finish-to-start dependencies.
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i j
(a) Basic Activity
Activity Name
Node (Event) i
j > i
Each activity should have a unique i – j value
Node (Event) j
Basic Logic Patterns for Arrow Diagrams
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2 A
(b) Independent Activities
4 10 B 12
3 A 6 B 9
(c) Dependent Activities
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2
A
(d) A Merge
4
6B 8
(e) A Burst
C
Activity C depends upon the completion of both Activities A & B
8
A6
2B
4C
Activities B and C both depend upon the completion of Activity A
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(f) A Cross
20
18C
16 D14
A12
B
Activities C and D both depend upon the completion of Activities A and B
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ExampleDraw the arrow network for the project given next.
Activity IPA
A -B A
C A
D B
E C,D
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Solution :
10
30
4020 50
C
D
A
B
E
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Dummy activity (fictitious)
* Used to maintain unique numbering of activities.
* Used to complete logic, duration of “0” *The use of dummy to maintain unique
numbering of activities .
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4 10
4 10
11
A
B
A
B
Divide node to correct
Dummy
(a) Incorrect Representation
(b) Correct Representation
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ExampleDraw the arrow network for the project given next.
Activity IPA
A -B A
C A
D B,C
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10 3020 40
C
DA
B
Solution :
10
30
4020 50
C
DA
BDummy
Improper solution
proper solution
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ExampleDraw the arrow network for the project given next.
Activity IPA
A -B A
C A
D B
E B,C
F C
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Solution :
10
30
40
20 60
C
EA
B
Dummy 1
50Dummy 2
D
F
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Removal of Redundant Dummies
A
A
A
A
B
B
B
B
C C
Original Diagram Diagram after removal of redundant dummies
(a)
(b)
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A
A
A
A
C
C
B
C
B B
Original Diagram Diagram after removal of redundant dummies(c)
(d)
B E
C
E
E E
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Activity Depends Upon Immediately Preceding Activity (IPA)
ABC
-----A
A, B
-----AB
B CA
Redundant
Relationship
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Activity List with Dependencies:
Activity Description Depends Upon
ABCDEFGHJKLM
Site ClearingRemoval of TreesExcavation for FoundationsSite GradingExcavation for Utility TrenchesPlacing formwork & ReinforcementInstalling sewer linesPouring concreteObtain formwork & reinforcing steelObtain sewer linesObtain concreteSteelworker availability
----------A
A, B, CA, B, C
B, C, J, MB, C, D, E, KD, E, F, G, L
--------------------
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Activity Description Depends Upon
ABCDEFGHJKLM
Site ClearingRemoval of TreesExcavation for FoundationsSite GradingExcavation for Utility TrenchesPlacing formwork & ReinforcementInstalling sewer linesPouring concreteObtain formwork & reinforcing steelObtain sewer linesObtain concreteSteelworker availability
----------A
A, B, CA, B, C
B, C, J, MB, C, D, E, KD, E, F, G, L
--------------------
Removing Redundant Relationships:April 10, 2023
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AOA Representation
H4040
G4545
C
F
D3535
1515
1010
55B
A
2020
M
2525J
3030
E
L
K
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NODE NETWORKS MTHOD (AON)
a) Independent Activities
10A
10A
20B
20B
Activity number
Activity name
b) Dependent Activities
20B
20B
10A
10A
Link
LinkB depends on A
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30C
30C
10A
10A
20B
20B
40 D40 D
c) A Merge Relationship
C depends on A & BD depends on C
d) A Burst Relationship
20B
20B
30C
30C
40D
40D
10 A10 A
B depends on AC depends on BD depends on B
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e) Start & Finish Dummy Activities
AA
CC
BB
EE
DDAA
StartDummyStart
DummyFinish
DummyFinish
Dummy
CC
BB
EE
DD
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ExampleDraw the arrow network for the project given next.
Activity IPA
A -B A
C A
D B
E C,D
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Solution :
A E
C
DB
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ExampleDraw the arrow network for the project given next.
Activity IPA
A -B A
C A
D B,C
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A
C
D
B
Solution : April 10, 2023
69696969
ExampleDraw the arrow network for the project given next.
Activity IPA
A -B A
C A
D B
E B,C
F C
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Solution :
A PF
C
DB
E
F
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Lags and Leads
In some situations, an activity cannot start until a certain time after the end of its Predecessor.Lag Lag is defined as a minimum waiting period between the finish (or start) of an activity and the start (or finish) of its successor.
Arrow networks cannot accommodate lags. The only solution in such networks is to treat it as a real activity with a real duration, no resources, and a $0 budget.
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Examples
Place Concrete
3
Strips Forms 2
3
A lag in a node network
Place Concrete Strips Forms Cure Concrete
A lag in an arrow network
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The term leadlead simply means a negative lag. It is seldom used in construction. In simple language: A positive time gap (lag) means ‘‘after’’ and a negative time gap (lead) means ‘‘before.’’
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Recommendations for Proper Node Diagram Drawing
Incorrect Correct
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A
B A B
A
B
A
BImproper proper
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Improper Proper
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Improper Proper
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A
B
C
Improper Proper
A
B
C
PS
(a) Do not startstart a network with more than one node
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A
B
C
Improper Proper
A
B
C
PF
(a) Do not endend a network with more than one node
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The Critical Path The Critical Path Method (CPM)Method (CPM)
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Suppose you decide with your friend to go in hunting trip .
You must do specific activity such that the trip well be at the right way. The following activity must be done .
IntroductionApril 10, 2023
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From chart you can see that the 3rd activity (preparing the jeep) have the longest period of time any delay with this activity leads to delay in the trip this activity is a “critical activitycritical activity”
Critical activity : An activity on the critical path any delay on the start or finish of a critical activity will result in a delay in the entire project Critical path : The longest path in a network from start to finish
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Steps Required To Schedule a Project
The preparation of CPM includes the following four steps:
1 -Determine the work activities:The project must be divided into smaller activities or tasks.
The activity shouldn’t be more than 14-20 days (long durations should be avoided)
Use WBS in scheduling by using an order of letters and numbers
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2 -Determine activity duration: Duration = Total Quantity / Crew Productivity The productivity has many sources:
1 .The company 2 .The market
3 .Special books
Note: Note: The scheduler must be aware about the non-working days , such as holydays or rain days, etc……
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Estimating Activity Duration
Time Interval Time Interval is selected according to the
nature of the activity (seconds - minutes…)
It is common practice in construction industry to use calendar day.
Use one and only one time unit for any schedule.
1. From company’s record
2. From standard estimating guide
3.Interviewing field personnel.
Sources
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Weather and Contingency Allowance
Two approaches for assignment of weather allowance:1. Add the Weather Allowance at the end of the project as a
separate activity.
2. Add Weather Allowance to those affected by the weather.
3.Add weather allowance at the end of each construction segment (site preparation, foundation, … etc.)
Contingency itemsOther activities can be added to allow for contingency such as strikes
Time ZeroThe close of the work period immediately preceding the start
of the project.
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3 -Determine the logical relationships:
This step is a technical matter and obtained from the project manager and technical team, and logical relationships shouldn’t confused with constraints
4- Draw the logic network and perform the CPM calculations
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5-Reiew and analyze the schedule:
1 .review the logic
2 .Make sure the activity has the correct predecessor
3 .make sure there is no redundant activity
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6- Implement the schedule: Definition: take the schedule from paper to the execution.
7-Monitor and control the schedule:
Definition: comparing what we planed with what actually done.
8-Revise the database and record feedback.
9-Resource allocation and leveling.(will discuss in chapter 6)
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The WBS (Work Breakdown Structure) IT is used to break down the project from one
main and relatively big entity into smaller, defined, manageable and controllable units, usually called work groups or tasks, or, at the finest level of detail (which is undesirable) activities
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Take care!!!
The deeper you go into the lower levels of the WBS, the more detailed knowledge you’ll need to know.
A good rule of thumb is the rule of 1-5-5-5, which entails that each level be broken down into a maximum of five lower levels.
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Who develops the WBS?
A WBS is developed by the A/E at the end of the design phase.
and/or by the bidders during the proposal (procurement phase).
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The CWBS (Contract Work breakdown Structure )After contract award, the project manager
expands the WBS into a contract work breakdown structure (CWBS).
as the initial step in the PLANNING process.
The extended CWBS must include the levels at which required reporting information is summarized for submittal to the Owner
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Uses of the WBS The WBS is used to report program status
externally to the Owner.
The CWBS is used internally to plan the program in detail and to collect status information on a periodic basis for the lowest level of the CWBS, namely the schedule activities.
The basis for technical planning and project achievement.
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The CWBS
it is a major task to undo.
Why???
Because cost collections begins at a CWBS element,
The individuals assigned the responsibility for WBS/CWBS development should never lose sight of the fact that the WBS is used for technical planning and status achievement.
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House1.0
Structural Work1.1
fine works
1.2
Sub-Structure
1.1.1
Super-Structure
1.1.2
Finishing 1.21
Doors & Windowsframes
1.2.2
Electrical Works
1.3
Earthwork1.1.1.1
Foundation1.1.1.2
Columns1.1.2.1
Roof slabs1.1.2.2
Conduiting1.3.1
Light Fittings1.3.2
Plaster1.2.1.1
Floor tile1.2.1.2
Excavation1.1.1.1.1
Backfilling1.1.1.1.2
Level 1
Level 2
Level 3
Level 4
Level 5
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Conclusion
The work breakdown structure defines the product elements (work packages).
And their interrelations to each other and to the product.
The WBS mostly ends with project tasks.
Using the tasks you can extract project’s activities.
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TYPES OF ACTIVITIES
1. Production ActivitiesThose that can be taken directly from plans
and specifications
2. Procurement ActivitiesProcurement of material and equipment
3. Management Decision ActivitiesActivities that can be created by
management to avoid certain situationsDelay ConcreteCompany VacationDeer Hunting
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Events and Milestones
An event: a point in time that is usually the start or finish of a certain activity(s)Duration = 0
Important events are called milestonesmilestones such as NTP and finish milestones such as Substantial Completion
An activity has a start date and a finish date
An event / milestone has a start date or a finish date
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ExampleDraw the logic network and perform the CPM calculations for the schedule shown next.
Activity IPA Duration A - 5B A 8C A 6D B 9E B,C 6F C 3G D,E,F 1
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In mathematical terms, the ES for activity j is as follows : ESj =max( EFi )
where (EFi) represents the EF for all preceding activities.
Likewise, the EF time for activity j is as follows :
EF j= ESj + Dur j
where Dur j is the duration of activity j
Forward pass: The process of navigating through a network from start to end and calculating the completion date for the project and the early dates for each activity
Forward pass calculationsApril 10, 2023
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A5
G1
C6
D9
B8
E6
F3
22,23
5,11
5,13
13,22
13,19
11,14
0,5
Solution : April 10, 2023
103
In mathematical terms, the late finish LF for activity j is as follows:
) LFj =min(LSk
where (LSk) represents the late start date for all succeeding activities.
Likewise, the LS time for activity j (LS j) is as follows:
LS j= LFj - Dur j
where Dur j is the duration of activity
Backward pass: The process of navigating through a network from end to start and calculating the late dates for each activity. The late dates (along with the early dates) determine the critical activities, the critical path, and the amount of float each activity has.
Backward pass calculationsApril 10, 2023
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Solution :
A5
G1
C6
D9
B8
E6
F3
22,23
5,11
5,13
13,22
13,19
11,14
0,5
22,23
13,22
19,22
16,22
5,13
10,16
0,5
CPM ( ES = LS , EF = LF , TF = FF = 0)
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Four Types Of Floats
There are several types of float. The simplest and most important type of float is Total Float (TF) Total float (TF): The maximum amount of
time an activity can be delayed from its early start without delaying the entire project.TF = LS – ES or TF = LF - EF orTF = LF - Dur - ES
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Free Float: may be defined as the maximum amount of time an activity can be delayed without delaying the early start of the succeeding activities
FFi = min(ESi+1) - EFi
where min (ESi+1) means the least (i.e., earliest) of the early start dates of succeeding activities
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In the previous example we can find the free float and total float for each activity as the following :
Activity C’s free float, FF = 11 - 11 = 0 daysAnd Activity C’s total float, TF =16 - 11= 5 days …… and so on.
Activity Duration
ES EF LS LF TF FF
A 5 0 5 0 5 0 0B 8 5 13 5 13 0 0C 6 5 11 10 16 5 0D 9 13 22 13 22 0 0E 6 13 19 16 22 3 3F 3 11 14 19 22 8 8G 1 22 23 22 23 0 0
Critical activity Note : We must always realize that FF ≤ TF
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Interfering float: may be defined as the maximum amount of time an activity can be delayed without delaying the entire project but causing delay to the succeeding activities.
TF = FF - Int. or Int. F = TF - FF
Independent float (Ind. F): we may define it as the maximum amount of time an activity can be delayed without delaying the early start of the succeeding activities and without being affected by the allowable delay of the preceding activities.
Ind. Fi = min(ESi +1 ) – max(LFi-1) – Duri
Note: make sure that Ind. F ≤ FF
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Node Format
Activity Name
Activity ID
Duration
ES EF
LS LF
TF FF
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Example
Activity Duration IPA
A 5 -
B 8 A
C 6 A
D 9 B
E 6 B,C
F 3 C
G 1 D,E,F
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Tabular Solution
Activity Duration ES EF LS LF TF
A 5 0 5 0 5 0
B 8 5 13 5 13 0
C 6 5 11 10 16 5
D 9 13 22 13 22 0
E 6 13 19 16 22 3
F 3 11 14 19 22 8
G 1 22 23 22 23 0
April 10, 2023
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A5
F3
D9
E6
C6
B8
G1
5, 13
0, 5 13, 19
5, 11
13, 22
11, 14
22, 235, 13
0, 5 16, 22
10, 16
13, 22
19, 22
22, 23
A5
D9
B8
G1
5
3
8
All dates above represent the end of the day
Graphic SolutionApril 10, 2023
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Example
Activity Duration IPA
A 5 -
B 6 A
C 5 A
D 3 A
E 3 B
F 4 B, C
G 4 D
H 7 B,C,G
I 8 E, F
J 2 F
K 3 H, J
L 2 I, J
April 10, 2023
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A5
D3
B6
C5
G4
E3
F4
H7
I8
J2
K3
L2
PF
April 10, 2023
115
A5
D3
B6
C5
G4
E3
F4
H7
I8
J2
K3
L2
PF
0, 5
0, 5
5, 11
5, 10
5, 8
11, 15
11, 14
8, 12
15, 17
15, 23
12, 19
23, 25
19, 22
25
25
23, 25
22, 25
15, 23
20, 22
15, 22
12, 15
11, 15
11, 15
5, 11
6, 11
8, 11
1
3
1
3
5
3 3
Graphic SolutionApril 10, 2023
116
Activity ES EF LS LF TF FFA 0 5 0 5 0 0B 5 11 5 11 0 0C 5 10 6 11 1 1D 5 8 8 11 3 0E 11 14 12 15 1 1F 11 15 11 15 0 0G 8 12 11 15 3 0H 12 19 15 22 3 0I 15 23 15 23 0 0J 15 17 20 22 5 2K 19 22 22 25 3 3L 23 25 23 25 0 0
Tabular SolutionApril 10, 2023
117
End-of-Day Convention
The dates on the activities represent the “end of day”. That’s why we always start with day 0: end of day 0 = start of day 1
This concept is not applied in computer programs. In computer programs start dates (ES, LS) represent the beginning of the day while finish dates (EF, LF) represent the end of the day
April 10, 2023
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Exercise Solution Using The Computer
A5
D3
B6
C5
G4
E3
F4
H7
I8
J2
K3
L2
PF
1, 5
1, 5
6, 11
6, 10
6, 8
12, 15
12, 14
9, 12
16, 17
15, 23
13, 19
24, 25
20, 22
25
25
24, 25
23, 25
16, 23
21, 22
16, 22
13, 15
12, 15
12, 15
6, 11
7, 11
9, 11
1
3
1
3
5
3 3
April 10, 2023
119
Comments on the Solution
Near-critical activities may be as important as critical activities
It is a good practice for the project manager not to give subordinates two sets of dates
PM has to choose one set of dates within the range of Early – Late
Management may reserve a number of days as “management float” or “time contingency”
April 10, 2023
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Float Discussion
Total float –in general- belongs to a path rather than the activity itself
If an activity uses “its” float, successors may lose some or all of “their” float
Total float versus free float
Total float is broken down into free float, independent float, and interfering float.
Researchers have come up with even more types
April 10, 2023
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The question is: “who owns the float”?
Float distribution attempts
Review the contract – what if it is not mentioned?
Float with resource leveling
Shifting activities within their float may affect:
Start / finish dates of succeeding activities
Resource usage: Labor and equipment (crews)
Materials: delivery, storage
Cash flow
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Lags in Node Networks
A lag is a minimum compulsory waiting period between the start/finish of an activity and the start/finish of the successor
Actual waiting period may be greater, but never less than the lag
Lags are very common with SS and FF relationships
A lead is a negative lag
The lag is added in the CPM’s forward pass calculations and subtracted in the backward pass
April 10, 2023
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Examples: Concrete curing (before formwork stripping
or reshoring)
Asphalt curing (before striping)
Waiting for a permit to be issued
Waiting for the delivery of a custom material or equipment
April 10, 2023
124
Example
Activity Duration IPA Lag
A 5 -
B 3 -
C 6 -
D 7 A
E 7 A
B 4
F 4 A,B,C
G 5 E
F 3
H 6 D
G 2
I 3 D,G
April 10, 2023
125
C6
B3
A5
G5
F4
E7
D7
H6
I3
4
3
2
PS PF
270
0 27
0, 5 5, 12
0, 3
0, 6
7, 14
6, 10
14, 19
21, 27
19, 22
21, 27
24, 2714, 19
14, 21
7, 14
7, 11
2, 7
0, 3
1, 7
Graphic SolutionApril 10, 2023
126
Activity ES EF LS LF TF FFA 0 5 2 7 2 0B 0 3 0 3 0 0C 0 6 1 7 1 0D 5 12 14 21 9 7E 7 14 7 14 0 0F 6 10 7 11 1 1G 14 19 14 19 0 0H 21 27 21 27 0 0I 19 22 24 27 5 5
Tabular SolutionApril 10, 2023
127
Constraints and the CPM
A Constraint is an externally imposed restriction affecting when an activity can start and/or finished
Constraints may conflict with logical relationships
Constraints are not alternatives for logic
April 10, 2023
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On a continuous path:
Activities A, B, and C are critical; but D, E, and F notWhy?
A6
B5
C3
D9
E5
F2
Software QuizApril 10, 2023
129
Effect of Imposed Finish Date Imposed Finish Date is the project’s completion
date, as specified in the contract or stipulated by the owner
When compared to the calculated finish date:
Calculated finish date < imposed finish date
• You are in good shape
• What happens if you enter the imposed date?
Calculated finish date > imposed finish date
• Negative float appears when you enter the imposed date
• You need to accelerate / crash the schedule
April 10, 2023
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Examples with Imposed Finish Dates
Repeat Example 3 with imposed finish date of 28 days
Repeat Example 3 with imposed finish date of 22 days
April 10, 2023
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Imposed Finish Date > Calculated Finish Date
A5
D3
B6
C5
G4
E3
F4
H7
I8
J2
K3
L2
PF
0, 5
3, 8
5, 11
5, 10
5, 8
11, 15
11, 14
8, 12
15, 17
15, 23
12, 19
23, 25
19, 22
25
28
26, 28
25, 28
18, 26
23, 25
18, 25
15, 18
14, 18
14, 18
8, 14
9, 14
11, 14
3 4
6 6 6 6
8
43 3
3
3
April 10, 2023
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A5
D3
B6
C5
G4
E3
F4
H7
I8
J2
K3
L2
PF
0, 5
-3, 2
5, 11
5, 10
5, 8
11, 15
11, 14
8, 12
15, 17
15, 23
12, 19
23, 25
19, 22
25
22
20, 22
19, 22
12, 20
17, 19
12, 19
9, 12
8, 12
8, 12
2, 8
3, 8
5, 8
-3
-3
-3
-2 -3
-3
-2 2
0 0 0 0
Imposed Finish Date < Calculated Finish Date
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Negative float is a situation that occurs when performing an activity even on its early dates, fails to meet the project’s imposed finish date or other constraint
It may occur in one of two cases:
Before construction starts
During construction (after normal start)
Negative FloatApril 10, 2023
134
Calendars
Each activity has to be assigned a calendar
Different crews working for different activities work on different calendars.
The crew working for the same activity may work 5 days/week at normal times then switch to 6 or 7 days/week
User has to be aware of the impact of such matter on the duration of activities and consequently the project
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Computer scheduling programs can handle calendars:Global, default, and other calendars
Recurring holidays
Work hours per day
Resource calendars
Scheduling in other countries
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Schedulers must take in account non-work days. This includes:
Scheduled non-work days such as:.
• Holidays,
• Shut-downs.
Unscheduled non-work days such as:
• Rain days (or severe weather),
• Other unforeseen interruptions
Distribution of unscheduled non-work days
Non-Work Days April 10, 2023
137
Event Times in Arrow Networks
The early event time, TE, is the largest (latest) date obtained to reach an event (going from start to finish).
The late event time, TL, is the smallest (earliest) date obtained to reach an event (going from finish to start).Example
Perform the CPM calculations, including the event times, for the arrow network shown below.
April 10, 2023
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10 30
40
20 60
C
EB 50
D
F
70
A
GH
10
5
7
8
9
4
5
8
d1d2
Arrow network for example
April 10, 2023
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The preceding logic is similar to that of the forward and backward passes: When you are going forward, pick the largest number. When you are going backward, pick the smallest number.
i jAct. NameDur.
TEi
TLi
TEj
TLj
CPM
April 10, 2023
140
10 30
40
20 60
C
EB 50
D
F
70
A
GH
10
5
7
8
9
4
5
8
d1
d2
10
10
7
0
0
15
10
10
19
19
24
2727
27
(0,10)(0,10)
(5,10)(0,5)
(0,7)(8,15)
(10,18)(11,19)
(10,19)(10,19)
(7,11)(15,19)
(19,24)
(22,27)
(19,27)(19,27)
April 10, 2023
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Float Calculations From Event Times
Total Float
TFij = TLj - TEi - Tij
Example ( In the previous network )
TF40-50 = TL50 – TE40 – T40-50
= 19 – 7 – 4 = 8
April 10, 2023
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Free Float
FFij = TEj - TEi – Tij
ExampleFF40-50 = TE50 – TE40 – T40-50
= 19 – 7 – 4 = 8
April 10, 2023
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Interfering Float
INTFij = TLj – TEj
ExampleINTF40-50 = TL50 – TE50
= 19 – 19 = 0
Independent Float
INDFij= TEj – TLi - Tij
ExampleINDF40-50 = TE50 – TL40 – T40-50
= 19 – 15 – 4 = 0
April 10, 2023
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Example
Activity Duration IPAs
A 2 --B 2 A
C 4 A
D 1 C
E 4 B,C
F 2 B
G 1 D
H 4 F,E
I 2 F
J 4 G,H
K 4 I,H
L 1 K,J
Draw a network for the following activities
April 10, 2023
145
A
2
C 4
D1
E
4
B
2
F
2
G
1
H
4
I
2
J4
L
1
K4
1 2 3
4
5
6
9 10
7
8
11 12 13
The Arrow Network will be: April 10, 2023
146
A
2
C 4
D1
E
4
B
2
F
2
G
1
H
4
I
2
J4
L
1
K4
1 2 3
4
5
6
9 10
7
8
11 12 13
0 2 4 6 14
6 6 10 14 18 19
147
Forward Pass calculations (ES, EF)April 10, 2023
147
A
2
C 4
D1
E
4
B
2
F
2
G
1
H
4
I
2
J4
L
1
K4
1 2 3
4
5
6
9 10
7
8
11 12 13
0 2 6 10 14
6 6 10 14 18 19
1413
backward Pass calculations (LS, LF)April 10, 2023
148
A
2
C 4
D1
E
4
B
2
F
2
G
1
H
4
I
2
J4
L
1
K4
1 2 3
4
5
6
9 10
7
8
11 12 13
0 2 4 6 14
6 6 10 14 18 19
147
0 2 6 10 14
6 6 10 14 18 19
1413
Specify the Critical PathApril 10, 2023
149
A
2
C 4
D1
E
4
B
2
F
2
G
1
H
4
I
2
J4
L
1
K4
1 2 3
4
5
6
9 10
7
8
11 12 13
0 2 4 6 14
6 6 10 14 18 19
147
0 2 6 10 14
6 6 10 14 18 19
1413
April 10, 2023
150
Activity
Duration
IPAs ES EF LS LF TF
A 2 -- 0 2 0 2 0B 2 A 2 4 4 6 2C 4 A 2 6 2 6 0D 1 C 6 7 12 13 6E 4 B,C 6 10 6 10 0F 2 B 4 6 8 10 4G 1 D 7 8 13 14 6H 4 F,E 10 14 10 14 0I 2 F 6 8 12 14 6J 4 G,H 14 18 14 18 0K 4 I,H 14 18 14 18 0L 1 K,J 18 19 18 19 0
Table of activitiesApril 10, 2023
151
A
B
C
D
E
F
G
H
I
J
K
L
2 4 6 8 10 12 14 16 18 20
Bar / Gantt chart Early Start / FinishEF = ES + D
Activity
Time
April 10, 2023
152
A
B
C
D
E
F
G
H
I
J
K
L
2 4 6 8 10 12 14 16 18 20
Bar / Gantt Chart Late Start / FinishLS = LF - D
Activity
Time
April 10, 2023
153
A
B
C
D
E
F
G
H
I
J
K
L
2 4 6 8 10 12 14 16 18 20
Bar / Gantt of the previous networkApril 10, 2023
154
Summary
i jTTEi
TLi
TEj
TLj
Direction Float TF
FF
Int. F
Ind. F
April 10, 2023
155
True or False:• Determining activities durations is primarily the
scheduler’s job
• You can find out the project’s estimated completion date after
• performing the forward pass only
• You can find out the project’s critical path after performing the forward pass only
• “Event” is another name for an activity
• “Task” is another name for an activity
• There could be more than one critical path in a CPM network
• Total float must be equal to or greater than free float
Quiz 4April 10, 2023
156
Definitions Activity, or taskActivity, or task: A basic unit of work as part of the total project that is easily measured and controlled. It is time- and resource consuming.
Backward passBackward pass: The process of navigating through a network from end to start and calculating the late dates for each activity. The late dates (along with the early dates) determine the critical activities, the critical path, and the amount of float each activity has.
Critical activityCritical activity: An activity on the critical path. Any delay in the start or finish of a critical activity will result in a delay in the entire project.
Critical pathCritical path: The longest path in a network, from start to finish, including lags and constraints.
.
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Early datesEarly dates: The early start date and early finish date of an activity.
EarlyEarly finish (EF)finish (EF): : The earliest date on which an activity can finish within project constraints.
Early start (ES): Early start (ES): The earliest date on which an activity can start within project constraints.
Event: Event: A point in time marking a start or an end of an activity. In contrast to an activity, an event does not consume time or resources.
Forward passForward pass: The process of navigating through a network from start to end and calculating the completion date for the project and the early dates for each activity.
Late dates: Late dates: The late start date and late finish date of an activity.
Late finish (LF): Late finish (LF): The latest date on which an activity can finish without extending the project duration.
Late start (LS): Late start (LS): The latest date on which an activity can start without extending the project duration.
April 10, 2023
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Precedence DiagramPrecedence Diagram
April 10, 2023
159
The Four Types Relationships
Activities represented by nodes and links that allow the use of four relationships:
1) Finish to Start – FS
2) Start to Finish – SF
3) Finish to Finish – FF
4) Start to Start – SS
April 10, 2023
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Finish to Start (FS) Relationship. The traditional relationship between
activities .
.Implies that the preceding activity must finish before the succeeding activities can start.
. .Example: the plaster must be finished before the tile can start .
Plaster Tile
April 10, 2023
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Star to Finish (SF) Relationship
.Appear illogical or irrational.
.Typically used with delay time OR LAG.
.The following examples proofs that its logical .
steelreinforcement
Erect formwork
Order concrete
SF
Pour concrete
5
April 10, 2023
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Finish to Finish (FF) Relationship
• Both activities must finish at the same time.
• Can be used where activities can overlap to a certain limit. Erect
scaffoldingRemove Old paint
sanding
painting inspectDismantle scaffolding
FF/1
FF/2
April 10, 2023
163
Start to Start (SS) Relationship
• This method is uncommon and non exists in project construction .
Spread groutClean surface
Set tile
SS
Clean floor area
April 10, 2023
164
Advantages of using Precedence Diagram
1. No dummy activities are required.
2. A single number can be assigned to identify each activity.
3. Analytical solution is simpler.
April 10, 2023
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Calculation
1)1) forward calculationsforward calculations
EF = ES + DEF = ES + D
Calculate the Lag LAGAB = ESB – EFA
Calculate the Free Float
FF = Min. (LAG)
April 10, 2023
166
2) 2) Backward calculationsBackward calculations
For the last task LF=EF , if no information deny that.
LS=LF-D
Calculate Total Float
TF = LS – ES OR LF – EF
TFi = Min (lag ij + TFj )
Determine the Critical Path
April 10, 2023
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Example
167Dur. E
S E
F FF TF LF
LS
A1 1
2002
1
B
9 2
110011
2
D
5 11
160016
11 4 16
200020
16 1 20
210021
20
F H
C
5 5
10307
2
E
4 10
143011
7 6 14
203317
11
G
54 3
1) Forward pass calculations 4) Backward pass calculations
2) Calculate the Lag ( LAGAB = ESB – EFA)
0
0 0 0 0
0 0
3) Calculate the Free Float (FF) FF = min.( LAG)
5) Calculate total Float (TF = LS – ES OR LF – EF)
April 10, 2023
168
168Dur. E
S E
F FF TF LF
LS
A
1 1
2002
1
B
9 2
110011
2
D
5 11
160016
11 4 16
200020
16 1 20
210021
20
F H
C
5 5
10307
2
E
4 10
143011
7 6 14
203317
11
G
54 3
6) Determine the Critical Path
0
0 0 0 0
0 0
The critical path passes through the critical activities where TF = 0
April 10, 2023
169
Resource Allocation and Resource Leveling
April 10, 2023
170
CATEGORIES OF RESOURCES
Labor
Materials
Equipment’s.
April 10, 2023
171
Labor
1. Salaried staff: like-project engineer, secretary.
2. Hourly workers: like-carpenters.
Equipment and Materials
1. Construction equipment and materials
2. Installed equipment and materials
April 10, 2023
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What is resource allocation?
Resource allocation(resource loading) :
Is the assignment of the required resources to each activity, in the required amount and timing.What Is Resource Leveling?
Is minimizing the fluctuations in day-to-day resource use throughout the project.
It is usually done by shifting noncritical activities within their available float. It attempts to make the daily use of a certain resource as uniform as possible.
April 10, 2023
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Why level Resources?
1. When the contractor adds the daily total demand for a specific resource for all activities he must provide the required amount, or work will be delayed.
2. Leveling may also be necessary for an expensive piece of equipment.
3. The main idea of resource leveling is to improve work efficiency and minimize cost during the life of the project.
Note: In general, materials do not need to be leveled
April 10, 2023
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Leveling Resources in a Project
oResource leveling is a mathematically complex process.
oThe resource-leveling method is called the minimum moment algorithm.
odiscussed by Robert B. Harris (1978) in his classic textbook, Precedence and Arrow Networking Techniques for Construction
April 10, 2023
175
Resource Profiles
Time
Reso
ur
ce n
eed
Actual, not leveled
Ideal
Leveled, realistic
April 10, 2023
176
Sort
Sort : the process of arranging activities in a list to certain specific order.
April 10, 2023
177
Priorities & Sorts
The activities making up the network must be listed in order of their priority of resources allocation.
The network shows the logical sequence of activities. (predecessor and successor).
The listing of activities must therefore reflects the dependency of some activities .
April 10, 2023
178
Activities Sort
Activity Duration ES TF Resource unit
A 1 1 0 8H
B 9 2 0 9H
C 5 2 3 7H
D 5 11 0 5H
E 4 7 3 4H
F 4 16 0 8H
G 6 11 3 2H
H 1 20 0 4H
Activity sort reflects the logic sequence of the network.
April 10, 2023
179
Major Sort
Activity Duration ES TF Resource unit
A 1 1 0 8H
B 9 2 0 9H
C 5 2 3 7H
E 4 7 3 4H
G 6 11 3 2H
D 5 11 0 5H
F 4 16 0 8H
H 1 20 0 4H
Activity sort with ES time as Major sort
April 10, 2023
180
Major & Minor Sorts
Activity Duration ES TF Resource unit
A 1 1 0 8H
B 9 2 0 9H
C 5 2 3 7H
E 4 7 3 4H
D 5 11 0 5H
G 6 11 3 2H
F 4 16 0 8H
H 1 20 0 4H
Activity sort with ES time as Major sort & TF as Minor Sort
April 10, 2023
181
A
B
C
D
E
F
G
H
2 4 6 8 10 12 14 16 18 20Time
8H
9H 9H 9H 9H 9H 9H 9H 9H 9H
7H 7H 7H 7H 7H
5H 5H 5H 5H 5H
4H 4H 4H 4H
8H 8H 8H 8H
2H 2H 2H 2H 2H 2H
4H
Act
ivit
y
Allocated resources April 10, 2023
182
2 4 6 8 10 12 14 16 18 20
Act
ivit
yTime
Total Labor 8 16 16 16 16 16 1313 13 13 7 7 7 7 7 10 8 8 8 4
Early start resources aggregation
A
B
C
D
E
F
G
H
8H
9H 9H 9H 9H 9H 9H 9H 9H 9H
7H 7H 7H 7H 7H
5H 5H 5H 5H 5H
4H 4H 4H 4H
8H 8H 8H 8H
2H 2H 2H 2H 2H 2H
4H
April 10, 2023
183
Resource Aggregation
Resources aggregation: is a summation of the resources that are used to carry out the program on a time period basis. For example, day to day , or week to week.
April 10, 2023
184
184Time
Total Labor 8 16 16 16 16 16 1313 13 13 7 7 7 7 7 10 8 8 8
Lab
or
2
4
6
8
10
12
14
16
Early start resources aggregation diagram (Histogram)
2 4 6 8 10 12 14 16 18 20
4April 10, 2023
185
Late start
Another histogram can be obtained if Late start considered. Shows different resources demand.
And many histograms can be obtained considering a different time in the network.
Each histogram shows different resources demand.
April 10, 2023
186
late Start Sorts
Activity Duration LS TF Resource unit
A 1 1 0 8H
B 9 2 0 9H
C 5 5 3 7H
E 4 10 3 4H
D 5 11 0 5H
G 6 14 3 2H
F 4 16 0 8H
H 1 20 0 4H
Activity sort with LS time as Major sort & TF as Minor Sort
April 10, 2023
187
A
B
C
D
E
F
G
H
2 4 6 8 10 12 14 16 18 20
Act
ivit
yTime
8H
9H 9H 9H 9H 9H 9H 9H 9H 9H
7H 7H 7H 7H 7H
5H 5H 5H 5H 5H
4H 4H 4H 4H
8H 8H 8H 8H
2H 2H 2H 2H 2H 2H
4H
Total Labor 8 9 9 9 16 16 1616 16 13 9 9 9 7 7 10 10 10 10 4
Late start resources aggregation
April 10, 2023
188
Time
Total Labor
Lab
or
2
4
6
8
10
12
14
16
8 9 9 9 16 16 1616 16 13 9 9 9 7 7 10 10 10 10 4
Late start resources aggregation diagram (Histogram)
2 4 6 8 10 12 14 16 18 20
April 10, 2023
189
189Time
Total Labor
Lab
or
2
4
6
8
10
12
14
16
8 9 9 9 16 16 1616 16 13 9 9 9 7 7 10 10 10 10 4
Early start vs Late start resources aggregation diagram (Histogram)
2 4 6 8 10 12 14 16 18 20
April 10, 2023
190
190Time
Total Labor
Lab
or
2
4
6
8
10
12
14
16
8 9 9 9 16 16 1616 16 13 9 9 9 7 7 10 10 10 10 4
Early start vs Late start resources aggregation diagram (Histogram)
2 4 6 8 10 12 14 16 18 20
April 10, 2023
191
Example
Dur. ES EF FF TF LF
LS
5 5
8
2
2
4
6
32
3
6
A
B
C
D
H
G
F
E
I
J
K1
6 0 0 6
1 6
11 0 0 11
6
6
8 0 6 14
12
8
14 8 8 22
16
11
14 0 0 14
11
11
13 0 6 19
17
10
16 6 6 22
16
6
10 0 6 16
12 13
16 6 6 22
19
14
22 0 0 22
14
22
24 0 0 24
22
April 10, 2023
192
Activity Duration ES TF Resource unit
A 5 1 0 8H
C 5 6 0 2H
D 2 6 6 4H
B 4 6 6 9H
H 6 8 8 5H
E 6 10 6 5H
G 3 11 0 2H
F 2 11 6 8H
I 3 13 6 5H
J 8 14 0 2H
K 2 22 0 6H
Activity sort with ES time as Major sort & TF and duration as Minor Sorts
Activities Sort April 10, 2023
193
2 4 6 8 10 12 14 16 18 20Time
Total Labor
8 8 8 8 8 15 1516 16 12 20 20 17 12 12 2 2 2 2 2
Early start resources aggregation
A
C
H
D
F
E
8H
2H 2H 2H 2H
5H 5H 5H
4H 4H
8H
I
J
K
5H 5H 5H
5H
2H
22 24
8H 8H 8H 8H
2H
5H 5H 5H
5H 5H 5H
8H
5H 5H
2H 2H 2H 2H 2H 2H 2H
6H 6H
2 6 6
B 9H 9H 9H 9H9H 9H 9H 9H
G 2H 2H 2H
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8 8 8 8 8 15 1516 16 12 20 20 17 12 12 2 2 2 2 2 2 6 6L
abo
r
2
4
6
8
10
12
14
16
Time
2 4 6 8 10 12 14 16 18 20 22 24
18
20
Early start resources aggregation diagram
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195
Activity Duration LS TF Resource unit
A 5 1 0 8H
C 5 6 0 2H
D 2 12 6 4H
B 4 12 6 9H
E 6 16 6 5H
H 6 16 8 5H
G 3 11 0 2H
F 2 17 6 8H
I 3 19 6 5H
J 8 14 0 2H
K 2 22 0 6H
Activity sort with LS time as Major sort & TF and duration as Minor Sorts
Activities Sort April 10, 2023
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2 4 6 8 10 12 14 16 18 20Time
Total Labor
8 8 8 8 8 2 2 2 2 2 2 15 15 11 11 12 20 2017 17
Late start resources aggregation
A
C
D
F
E
8H
2H 2H 2H 2H
5H 5H
4H 4H
8H
I
J
K
5H
2H
22 24
8H 8H 8H 8H
2H
5H 5H 5H
8H
5H 5H
2H 2H 2H 2H 2H 2H 2H
6H 6H
17 6 6
5H
B 9H 9H 9H 9H
G 2H 2H 2H
H 5H 5H 5H 5H 5H 5H
April 10, 2023
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Lab
or
2
4
6
8
10
12
14
16
Time
2 4 6 8 10 12 14 16 18 20 22 24
18
20
8 8 8 8 8 2 2 2 2 2 2 15 15 11 11 12 20 20 17 17 17 6 6
Late start resources aggregation diagram
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Lab
or
2468
101214161820
Lab
or
2468
101214161820
Late start
Early start
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Smoothing/Leveling
Let us program activity F to start by its late start day which is day 17.
And activity I to start by day 14.
The resulting resources aggregation histogram will be as follows:
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200
2 4 6 8 10 12 14 16 18 20Time
Total Labor
8 8 8 8 8 15 1516 16 12 12 12 12 12 12 7 10 10 2 2Early start resources aggregation
A
C
H
D
F
E
8H
2H 2H 2H 2H
5H 5H 5H
4H 4H
8H
I
J
K
5H 5H 5H
5H
2H
22 24
8H 8H 8H 8H
2H
5H 5H 5H
5H 5H 5H
8H
5H 5H
2H 2H 2H 2H 2H 2H 2H
6H 6H
2 6 6
B 9H 9H 9H 9H9H 9H 9H 9H
G 2H 2H 2H
April 10, 2023
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Lab
or
2
4
6
8
10
12
14
16
Time 2 4 6 8 10 12 14 16 18 20 22 24
18
20
8 8 8 8 8 15 15 16 16 12 12 12 12 12 12 7 10 10 2 2 2 6 6April 10, 2023
202
Smoothing/Leveling
Let us program activity H to start by its late start time.
So its resources demand starts with its Late start date.
The resulting resource aggregation and histogram will be as follows:
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203
2 4 6 8 10 12 14 16 18 20Time
Total Labor
8 8 8 8 8 15 1516 16 7 15 15 12 7 7 7 7 7 7 7
A
C
H
D
F
E
8H
2H 2H 2H 2H
5H 5H 5H
4H 4H
8H
I
J
K
5H 5H 5H
5H
2H
22 24
8H 8H 8H 8H
2H
5H 5H 5H
5H 5H 5H
8H
5H 5H
2H 2H 2H 2H 2H 2H 2H
6H 6H
7 6 6
B 9H 9H 9H 9H9H 9H 9H 9H
G 2H 2H 2H
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8 8 8 8 8 15 15 16 16 7 15 15 12 7 7 7 7 7 7 7 7 6 6
Lab
or
2
4
6
8
10
12
14
16
Time 2 4 6 8 10 12 14 16 18 20 22 24
18
20
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Smoothing/Leveling
In case activity D is split able activity. It could be interrupted to be carried out in tow parts.
Let us program activity B to start by 7th day .
And activity H to starts by its Late start date.
And activity E to start by day 14.
The resulting resource aggregation and histogram will be as follows:
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2 4 6 8 10 12 14 16 18 20Time
Total Labor
8 8 8 8 8 6 1111 11 11 10 10 11 12 12 12 12 12 12 7
Early start resources aggregation
A
C
H
D
F
E
8H
2H 2H 2H 2H
5H 5H5H
4H
8H
I
J
K
5H 5H 5H
5H
2H
22 24
8H 8H 8H 8H
2H
5H 5H 5H
5H 5H 5H
8H
5H 5H
2H 2H 2H 2H 2H 2H 2H
6H 6H
7 6 6
B 9H 9H 9H 9H
G 2H 2H 2H
4H
April 10, 2023
207Total Labor
Lab
or
2
4
6
8
10
12
14
16
Time 2 4 6 8 10 12 14 16 18 20 22 24
18
20
8 8 8 8 8 6 11 11 11 11 10 10 11 12 12 12 12 12 12 7 7 6April 10, 2023
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Early Start OR Early Finish
There are many solutions between the limits of Early Start and Early Finish.
The optimal solution is zero fluctuation histogram. Which is hard to be achieved.
It is preferred to solve the problem
toward the Early start resources aggregation diagram.
WHY ?!
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Because if there are labor availability problems to be overcome, they will occur in the early beginning of the project.
By other words, if the program based on the Late Start date, it means that all the activities are Critical, and any labor problem will affect the project completion.
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Allocation within resources restraints
Another situation which you may face in practice is the restricted resources availability.
Where you have to carry out the job with the available resources only.
In this case the project duration may be prolonged to suit the availability of the restricted resources.
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Rules for scheduling activities with limited resources
1) schedule activities to start as soon as their predecessors have been completed.
2) if more than one activity using a specific limited resources can be scheduled, priority is given to the activity with early Late Start. ( LS as Major Sort)
3) if tow or more activities have the same Late start, give priority to the activity with least Total Float. (TF as Minor Sort)
4) if the activities have the same Total Float in the minor sort, give the priority to the activity with the Largest Number of Resources.
5) If the activities are tied in the number of resources, give priority to the activity that has already started.
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A
1 1
2002
1
B
9 2
110011
2
D
5 11
160016
11 4 16
200020
16 1 20
210021
20
F H
C
5 5
10307
2
E
4 10
143011
7 6 14
203317
11
G
Dur. ES EF FF TF LF
LS
Resources
Activity desc.
8H 9H 5H 8H 4H
2H4H7H
ExampleApril 10, 2023
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Activity Duration ES TF Resource unit
A 1 1 0 8H
B 9 2 0 9H
C 5 2 3 7H
E 4 7 3 4H
D 5 11 0 5H
G 6 11 3 2H
F 4 16 0 8H
H 1 20 0 4H
Activity sort with ES time as Major sort & TF as Minor Sort
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Assume that the available labors in the company restricted to 10 helpers, and the company decided to carry out the job without resorting to hire more labor.
The resulting program will exceed the Early finish date based on the network.
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215Time
Total Labor 8 16 16 16 16 16 1313 13 13 7 7 7 7 7 10 8 8 8
Lab
or
2
4
6
8
10
12
14
16
Early start resources aggregation diagram (Histogram)
2 4 6 8 10 12 14 16 18 20
4April 10, 2023
216
Resources aggregation diagram
4 8 12 16 20 24A
ctiv
ity
Time
8 9
ABC
DE
FG
8H
9H
7H
5H
4H
8H
2H
4H
2 6 10 14 22 26Time
18
9 9 9 9 9 9 9 9 7 7 7 7 9 9 9 9 7 10 2 2 4
2
4
6
8
10
Lab
or
12LaborLimit
9H 9H 9H 9H 9H 9H 9H 9H
7H 7H 7H
4H 4H 4H
5H
2H
5H
2H
5H
2H
5H
2H 2H
8H 8H
10 10Total Labor
H
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Money and network schedules
Reminder, cost was one of the elements of project constraints triangle ( COST, TIME & QUALITY).
An effective management tries to minimize and integrate the above mentioned elements.
CPM provides a mean for relating time and money.
The application of resources to a project (materials, manpower and machinery) related to another resource which is MONEY.
The value of the resources for each activity represents a component of project cost.
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Hint
Construction costs includes :
1 )Materials costs.2 )labor costs.
3 )plant and equipment costs4 )overhead costs and profit .
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Example
Dur. ES EF FF TF LF
LS
5 5
8
2
2
4
6
32
3
6
A
B
C
D
H
G
F
E
I
J
K1
6 0 0 6
1 6
11 0 0 11
6
6
8 0 6 14
12
8
14 8 8 22
16
11
14 0 0 14
11
11
13 0 6 19
17
10
16 6 6 22
16
6
10 0 6 16
12 13
16 6 6 22
19
14
22 0 0 22
14
22
24 0 0 24
22
April 10, 2023
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Activity Duration ES TF )Cost( $
A 5 1 0 650C 5 6 0 1300D 2 6 6 400B 4 6 6 1450H 6 8 8 500E 6 10 6 1100G 3 11 0 600F 2 11 6 350I 3 13 6 1000J 8 14 0 1300K 2 22 0 200
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2 4 6 8 10 12 14 16 18 20Time
Total cost
200 100 200 100 50 550550 400 500 750 450 600 300 350 150 200 100100150
A
C
H
D
F
E
200
150 100 200 200
200 200 100
200 200
150
I
J
K
50 100 150
200
100
22 24
100 200 100 50
150
200 50 50
150 100 150
100
100100
100 150 200 100100 150 100
100 100
100 100 100
B 9H 9H 9H 9H100250 300 100
G 200 200 200
350
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100
200
300
400
500
600
700
800
Time 2 4 6 8 10 12 14 16 18 20 22 24
Total cost 200 100 200 100 50 550550 400 500 750 450 600 300 350 150 200 100100150 100 100 100350
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Cash Flow
It is quite significant to the contractor to know the amount of money that would be spent in each stage of the project.( Expenditures)
And compare it to the amount of money that would be received. (income)
Overtrading Overtrading: arises when the current
liabilities of a company exceed the current assets, even though the business is solvent.
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224
400800
120016002000240028003200
Time 2 4 6 8 10 12 14 16 18 20 22 24
36004000
Cash Flow Diagram
Total cost
44004800
5200560060006400
200 100 200 100 50 550550 400 500 750 450 600 300 350 150 200 100100150 100 100 100350
200 300 500 600 650 1550 21002500 30003750 4200 4800 51005450 5600 58005900600061506250635064501000Com. cost
Com. cost = Cumulative Cost
$
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Time (Months) Cash Flow Curve for revenue and expenditures
CumulativeExpenditures & Revenues
Revenues
ExpendituresRetainage Release
Amount of NegativeCash Flow
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Cash Flow Example
$
Time
early
plannedlate$
$$$
$$
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Spending
Cash Flow: In and Out
Time
$
Reimbursement
Profit
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Cash Flow Analysis
Cash flow analysis consists of a detailed examination of funds disbursement (expenditures) and the receipt of revenue.
Cash flow shows if surplus fund available during project, or if negative cash position will occur during construction.
The cash position of contractor during project whether positive or negative is important.
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Negative cash position
Negative cash position means that the revenues obtained from a project insufficient to meet the financial obligations (expenditures) of the project.
In this case other fund from the company or from outside sources must be used.
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Positive cash position
Positive cash position means that the revenues obtained from a project exceed the financial obligations (expenditures) of the project.
In this case surplus (extra) fund available with the contractor.
And the contractor may invest this surplus funds for short duration.
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Materials Management
Is defined as the planning and controlling of all necessary efforts to ensure that the correct quality and quantity of materials and equipment are appropriately specified in a timely manner, are obtained at a reasonable cost, and are available when needed.
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Materials management functions
Identifying.
Acquiring.
Distributing.
Disposing.
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Objectives of materials management
Ensure that materials meet the specifications and are on hand when and where required.
Obtain the best value for purchased materials.
Provide efficient, low-cost transport, security, and storage of materials at construction sites.
Reduce any surplus to the lowest level possible.
April 10, 2023
Schedule Updating Schedule Updating and Project Controland Project Control
234
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Schedule updating
Schedule updating is just one part of the project control process.
Schedule updating must reflect
Actual work , and involves change orders (CO) .
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What is an updated schedule?A revised schedule reflecting project information at a given data date regarding completed activities , in progress activities , and change in the logic , cost , and resources and allocated at any level .What is data date?
The data date is the date as of which all progress on a project is reported. It is also called as- of datas- of date and status date status date .
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Why Update Schedules?
Schedules (like cost estimates) are always prepared before the project begins. However, updates must take place routinely for the following two reasons:
a. Unintentional events
b. Intentional changes
Schedules without updating, monitoring, controlling, and corrective action are useless
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What kind of information is needed for updating schedules ?
1. Past information : what has happened since the last update ?. 2. Future information : the future category comprises any changes to schedule or schedule items.
Future changes are two types :
A. logic – driven changes
B. user’s changes
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Frequency of updating
Construction schedules may be updated monthly , biweekly, weekly, or according to another time interval .
Project managers must achieve a delicate balance between updates is too long and one is too short
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Updating schedules and pay requests
In many cases , project updating is tied to payment requests.
In general , a pay requests is a document submitted by the contractor to the owner , asking for payment for work actually performed (whether .finished or not)during the period since the last pay request.
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Effect of adding or deleting activities on logic
An activity in a schedule is usually like a link in a chain ; removing a link may disturb the whole chain if it is not done properly.
For example :Deleting activity AS520 in the partial network shown in figure will remove any link between activities in each side.
AS210
AS250
AS260
TL160
AS245
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It is strongly recommended that the scheduler review the logic before making any change by first printing a logic report showing all predecessors .and successors for the activity be deleted.
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Steps for Updating a Schedule
1. The Schedule activity list
• Filter out completed activities
• Eliminating activities in the far future?
• Scheduler sends it to the project PM / superintendent
• Possibility that PM/superintendent wants to change past events
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Example 1: No Cost April 10, 2023
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Example 2: With Cost April 10, 2023
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2. The PM (or superintendent) fills up the form, signs and dates it; and submits it back to the scheduler
It is a good idea for the PM to keep a copy for his/her records
It is a good idea to assign “ink colors” to different parties
3. The scheduler enters the info in the computer and updates the project, signs and dates the forms
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4. The scheduler prints a preliminary report and discusses it with the PM
It is a good idea to produce a summary report (what happened between last update and this update)
Based on this discussion, the scheduler makes any necessary adjustments to the schedule or reports
Any changes to the schedule requested by the PM have to be documented by the scheduler
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Myths/Misconceptions About Schedule Updating
We always produce a complete schedule before the commencement of construction. We just don’t update it, We trust our field staff and subcontractors to follow it.
We update projects only when there is a “need” for the update
Everything is going well. There is no need for an update
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Quiz 6
True or False:
1. Updating is needed for projects that have duration of at least one year or a minimum budget of QAR 10 million
2. Data date is the date all information was entered in the computer
3. In updating schedules, we must enter not only actual work progress but also any future changes
4. Negative float is an indication that the schedule is not meeting its expected completion date or an interim imposed date
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Project Control
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Project control is the continuous practice of1. monitoring work progress,
2. comparing it to baseline budget and schedule,
3. detecting any deviations and their causes, and
4. taking a corrective action wherever and whenever necessary
The ability to determine a project status as it relates to the time and schedule selectedAlso called project tracking
Project monitoring?
Project Control April 10, 2023
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Project control is needed because projects never run exactly as planned.
Project control is a cyclical iterative task: do small part of the work and compare to baseline, do corrective measure, adjust plan (if needed), do another part of the work, and so on..
Project control requires measuring work progress and calculating activities percent complete
Why Project Control?April 10, 2023
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What is a baseline schedule?A baseline schedule is a schedule prepared by the contractor ,usually before the start of the project ,and used for performance comparison.
Baseline Budget: The project’s original approved budget including any approved changes
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Percent Complete
Percent Complete (PC or PCT): is an estimate, expressed as a percent, of the amount of work that has been completed on an activity or a work breakdown structure component. (PMBOK 2008)
Percent complete may be used to estimate:
Activity
Groups of activities / assembly / work package
Project
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Types of Percent Complete
Depending on the type and nature of the activity, percent complete may be calculated using one of several methods that may yield different results
Some methods are more subjective than others
None of these methods is wrong. None of them is uniquely considered the right method.
Most importantly: Know exactly what each percent complete means
Pick one or two parameters to use and then be consistent
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Major objectives for a good control plan:
1. Should accurately represent the work.
2. Permit deviations to be detected, evaluated and forecasted.
3. Should make provision for periodic corrective actions.
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Level of Control
Small projects - low cost - short duration
Detailed network
Reporting mechanism
Middle-sized projects (300 activities)
Detailed network
Summary network
Area and craft network
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Monitoring the Project1.Feedback from direct contact
Efficient but requires close cooperation between the manager and field personnel.
2. Feedback from photography Record progress and provide permanent
documentation of the work. Tell nothing about the time taken to perform
the work.
3. Feedback from check-off list Planner prepares a check-off list that is
started, to be continued, or to be finished in the next time interval.
Effective if the reporting periods are short “Daily, Weekly” and small number of activities involved.
Disadvantage: false reporting
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4.Feedback from bar chart.
5.Feedback from networks
Advantage:Superintendent has complete information
about the status of the project.Disadvantage:
Diagram may appear confusing to field personnel.
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Setting the Target Schedule
Early Start Schedule: As Target for ControlProblem:
Required high effort to keep the plan working.
Late Start Schedule As Target for ControlProblem:
Because every activity is timed to start as its latest, project overruns are sure to follow.
Activities may be positioned early or late start or somewhat in between.
Non-critical activities allow intermediate start.
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Anticipated target S-Curve April 10, 2023
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The S-Curve fieldApril 10, 2023
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Sample Project Cost Data
Activity
Duration (Days)
Cost Rate
($/Day)
Total Cost
($)
A 2 500 1,000 B 17 200 3,400 C 3 300 900 D 5 100 500 E 6 2,000 12,000 F 2 500 1,000 G 1 1,000 1,000
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Early Start TreeApril 10, 2023
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Late Start TreeApril 10, 2023
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Target NetworkApril 10, 2023
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Project S-Curve April 10, 2023
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Actual Versus Target S-CurvesApril 10, 2023
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Earned Value Analysis
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Earned Value (EV) Analysis: Earned Value analysis is an integrated cost-schedule approach to monitor and analyze the progress in a project.
Earned Value Management (EVM), started in the 1960’s as a method for integrated project cost and schedule control, was designed by the U.S. Air Force and named the Cost/Schedule Planning and Control System.
In 1967, it became U.S. DOD policy and was renamed Cost/ Schedule Control Systems Criteria, or C/SCSC
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The Concept of EVM
The concept of Earned Value is simple; at any given point find out:
1. The cost of work you have actually done (ACWP),
2. The cost of work you planned to do by this date (BCWS),
3. The amount earned for work performed (BCWP),
4. Calculate schedule and budget variances (SV, CV)
5. Analyze causes for major variances and suggest remedies,
6. Extrapolate these variances to the end of the project (FSV, FCV).
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Foundations of modern cost control
What’s more important?• Knowing where you are on schedule?
• Knowing where you are on budget?
• Knowing where you are on work accomplished?
Earned Value Analysis (EVA) addresses all three:
• It compares the PLANNED amount of work with what has actually been COMPLETED to determine if COST, SCHEDULE, and WORK ACCOMPLISHED
are progressing as planned.
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EVA Terminology
BCWS – Budgeted Cost of Work ScheduledPlanned cost of the total amount of work scheduled to be performed by the milestone date. (a.k.a. your original plan)
BCWP – Budgeted Cost of Work PerformedThe planned (not actual) cost to complete the work that has been done.Also known as “Earned Value”
ACWP – Actual Cost of Work PerformedCost incurred to accomplish the work that has been done to date.
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Input data for EVA
Activity schedule, usually in the form of a bar chart.
Budgeted cost for each activity.
Percent complete for each activity.
Cost to date for each activity.
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Information Needed to Compute Budgeted Cost of Work Scheduled (BCWS)
Activity budget at completion (BAC)
Activity schedule
Data date
Budgeted Cost of Work Performed (BCWP)Activity budget at completion (BAC)
Physical activity progress as a percentage of its total work
Actual Cost of Work Performed (ACWP)
Each activity’s cost to date from the job costing system
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Earned Value Reporting - Costs
ACWP
BCWPCPI
ACWPBCWPCV
CPI = 1, on budgetCPI < 1, over budgetCPI > 1, under budget
Budgeted Cost of Work Performed (BCWP) = earned value of project
Actual Cost of Work Performed (ACWP)
Cost Variance (CV)Difference between earned and actual costs for
the completed work
Cost Performance Index (CPI or CI)
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Earned Value Reporting - Schedule Budgeted Cost of Work Performed (BCWP)
Budgeted Cost of Work Scheduled (BCWS)
Schedule Variance (SV)Difference between the value of work that was planned
for completion and the value of the work that was actually completed
Schedule Performance Index (SPI or SI)
BCWS
BCWPSPI
BCWSBCWPSV
SPI = 1, on scheduleSPI < 1, behind scheduleSPI > 1, ahead of schedule
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Earned Value Reporting
Nabil Dmaidi
278
(earned)
(actual)
(budgeted)
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Example
A simple problem will help to illustrate the application of the principles of earned value . A project has been defined that consist of 12 activities for which the estimated cost and duration have been defined see figure .After three and a half month , the activates 1,2,4,5,7 are completed and (6) is one half complete and(8) is three –fourth complete and (3) is half complete. The incurred cost to date are 152000$ . What is the status of this project in terms of the schedule and the budget?
Solution
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Activity cost m1 m2 m3 m4 m5 m6
1 22000$
2 10000$
3 18000$
4 30000$
5 50000$
6 40000$
7 6000$
8 16000$
9 13000$
10 4000$
11 34000$
12 14000$
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Solution
ACWP =152000$
BCWS=22000+30000+50000+10000+18000+0.5(40000+6000+16000)=161000$
BCWP=22000+30000+50000+10000+6000+0,5(40000)+0.75(16000)+0.5(18000)= 159000$
SV= BCWP-BCWS= -2000$ its behind schedule
CV=BCWP-ACWP= 7000$ below the budget
EAC=ACWP+(BAC-BCWP)=152000+(257000-159000) = 250000$
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Earned Value: Cost and Time Status
$ +
Time
III
III IV
-
- +
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EVA: The CurveApril 10, 2023
284
Quiz 7
True or false:1. Project control is to be practiced by both contractor and
owner
2. Project monitoring is part of project control
3. For assistance in calculating progress payments, percent
4. complete for the project is more important than percent complete of individual activities
5. It is possible that different parties compute the “project percent complete” and come up with different estimates, yet none of them is wrong!
6. It is possible to have the scheduler report saying the project is behind schedule while the earned value analysis is showing a positive schedule variance.
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Time-Cost Trade-OffTime-Cost Trade-Off
Some amount of knowledge brings more……
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Time /cost trade –off analysis
Time /cost trade –off analysis is the compression of the project schedule to achieve a more favorable outcome in term of project duration , cost , and projected revenues
Objective of time /cost trade-off
-compress project to an acceptable duration
-minimize total project costs
Done by selectively crashing specific activities to shorten project duration
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Time /cost trade –off analysis
You might think that total project costs will increase when we begin to crash activities
But ,total project cost consist of both indirect (project –based ) costs (PBC) and activity – based cost (ABC )
-ABC goes up when we crash activities in an effort to finish the project early
-but ,PBC (the indirect cost ) goes down if we finish the project early
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What Is ‘‘Accelerating’’ a Project?
Accelerating a project means shortening the normal duration of the project schedule .
(also called schedule compression).
schedule crashing
Schedule acceleration
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Why Accelerate a Project?
1. The contractor’s ‘‘normal’’ finish date in the planned schedule does not meet the imposed finish date of the contract.
2. After starting construction and completing a certain percentage of the project, the contractor realizes that the project is behind schedule.
3 -when the contractor may have a contractual monetary incentive to finish ahead of schedule.
4- Sometimes, especially when the economy is doing well, finishing early
means—to the contractor—starting another job earlier
and, thus, making more profit.
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Schedule Compression: Multiple Paths
Path 1
Path 2
Path 3
Path 4
Path 5
Path 6
Path 7
Path 8
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
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Cost Changing with Schedule Acceleration
Direct Cost Indirect Cost
Total Cost
Cost $
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Cost
For the following discussions it is important to remember:
Direct costs: Related to putting the facility components in place. They represent the resources used by an activity. (material, labor and equipment).
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Indirect job costs (job overhead): costs that could not be attributed to a specific work item. (such as, site offices, superintendents, security fence & etc.)
These costs are generally incurred whether or not productive work achieved.
Longer project duration will result in higher indirect costs.
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Operating Overhead costs (company overhead): If the cost cannot be attributed to any specific job, they are operating overhead costs, costs of running business. (head office costs, communications & etc).
These costs continue as long as the company exists even one project is running.
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Logic of Time-Cost Trade-Off
Assumption: increasing or decreasing an activity’s duration will lead to increased direct costs for that activity.
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Project duration
General relation of direct costs to project duration
Direct Costs
Direct costs
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Assumption: decreasing a project’s duration will lead to lower indirect costs.
Project duration
General relation of indirect costs to project duration
Indirect Costs
indirect costs
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Assumption: A project’s duration can be decreased by decreasing the duration of one or more critical activities on the critical path.
Assumption: Decreasing a project’s duration may increase or decrease the total cost of a project depending upon whether the additional direct costs required to decrease the activity duration are greater or less than indirect costs savings of decreasing the project’s duration.
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Project duration General relation of project costs to project duration
Project Costs
Direct costs
indirect costs
Total project costs
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Graph analysis
A project’s total costs combines direct costs and indirect costs. Therefore, the curve of total costs versus duration involves adding the cost amounts of direct and indirect costs curves.
Remember, the direct costs curve has a negative slope (direct costs increase as duration decrease) and indirect costs curve has a positive slope (indirect costs decrease as duration decreases).
So, the slope of the total costs curves at any point depends whether the slope of direct costs curve less than that of indirect cost curve.
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How does accelerating a project work
The duration of the project is equal to the duration of the critical path .Thus to shorten the duration of the entire project ,shorten the duration of the critical path.
The cost will vary depending upon which activity duration decreased.
Usually, select the activity with least shortening costs. (lowest additional cost per day of shortening) to minimize the additional costs of shortening
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Reducing Project Duration
-As the critical path of the network decreased, some non-critical activities
lose some amount of their total float .
A
B
C
D
F
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-Thus, the extent to which an activity can be shortened and still has the effect of shortening the project is limited by the amount of total
float exists in the parallel activities .
A
B
C
D
F
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-As the projects duration decreases, the number of critical paths through the network increases .
A
B
C
D
F
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-If more than one critical path exist, it is necessary to reduce all critical paths in the network simultaneously, which becomes
expensive .
A
B
C
D
F
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Four Different Solutions for Each Network
The schedule can be viewed in several different ways in order to satisfy the client. A client may with to perform the project in the lease cost, or in the least time. Or in any manner satisfies him.
1) All Normal: the original network and activity duration result in all normal solution, based on each activity being performed in its “NORMAL” least cost manner.
Remember, it is not necessarily the least cost or least time solution to schedule a project.
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2) Least Cost: considering both direct and indirect costs, it may be possible to find a project duration that minimizes these total costs. By paying more to decrease one or more critical activity (direct cost) and save greater indirect costs. (Means that the result will be total cost saving.)
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Project duration General relation of project costs to project duration
Project Costs
Direct costs
indirect costs
Total project costs
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3) Least Time: A project can be shortened beyond its least cost duration. Until a point reached where no activities in the critical path can be physically shortened regardless of how many resources are applied. (results in higher costs)
4) All crash: in this solution, every activity has been shortened as much as physically possible. Its duration the same as the least time solution, but its costs greater. Because the direct cost increases without further reductions in the indirect costs.
A fully crashed schedule occurs when all activities shortened to their shortest possible duration
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All crash It is not an efficient approach since
some non-critical activities will be shortened without having any shortening influence on the project duration.
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Logically reducing Project Duration
The logical approach is to shorten those activities that contribute to reduce the project duration.
To begin the time-cost trade-off in a rational manner, basic calculations needed.
First compute the early start and early finish times for each activity
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ExampleReducing Project Duration to shortest possible duration
Dur. ES EF FF TF LF
LS
1 6
3
5
3
7 73
7
8
A
B
C
D G
F
E H
K
L1
2
2
8
2
5
5
13
9
16
9
12
2
9
16
23
16
19
23
28
5
J16
21
0
0
0
0
3
0
0
00
0 4
1
0
2
4
2
1
00
9
2
00
9
3
11
12
9
70
16
13
44
16
9
00
20
12
73
23
16
00
23
18
22
23
20
44
28
23
00
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By computing the link lag values between activities.
(Lag = ESB – EFA). It is logical that there is at least one path between the first activity and last activity where lag values are 0.
These activities forming the critical path. (other solution can be derived by computing TF).
In the previous network. Activity A,B,F,H and L forming the critical path.
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To shorten the project’s duration it is essential to shorten on of the critical activities. A or B or F or H or L.
Without shortening the project will end after 28 days with a cost of 5300 $.
This is the normal duration cost. And any decrease in duration will increase the direct cost.
The following table shows information about activities.
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Activity Cost / day
Normal Duration
Crash Duration
Normal Cost
Crash Cost
Days to shorten
A - 1 1 800 800 0B 200 7 4 1000 1600 3C 100 6 4 300 500 2D 400 3 2 400 800 1E 50 3 1 100 200 2F 150 7 5 500 800 2G 300 8 4 200 1400 4H 250 7 6 350 600 1J 75 5 3 700 850 2K 500 3 2 500 1000 1L 350 5 4 450 800 1
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Identifying activities for 1st compression cycle
Activity A B F H L
Cost/day
- 200$ 150$ 250$ 350$
F : Least cost activity to shorten
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From the previous table, it can be noticed that activity F has the least incremental shortening cost. ( 150 $ per day).
E.g. Shortening F for 2 days costs 150 x 2 = 300 $.
Bear in mind, activities for shortening selected based on cost per day. Not on cycle cost basis.
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How many days activity F could be shortened?
The answer in computing the Network Interaction Limit (NIL).
So, reducing activity F by 2 days will affect the link lag values of the succeeding activities and TF of parallel activities
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Dur. ES EF FF TF LF
LS
1 6
3
5
3
7 73
7
8
A
B
C
D G
F
E H
K
L1
2
2
8
2
5
5
13
9
16
9
12
2
9
16
23
16
19
23
28
5
J16
21
0
0
0
0
3
0
0
00
0 4
1
0
2
4
2
1
00
9
2
00
9
3
11
12
9
70
16
13
44
16
9
00
20
12
73
23
16
00
23
18
22
23
20
44
28
23
00
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Dur. ES EF FF TF LF
LS
1 6
3
5
3
7 73
5
8
A
B
C
D G
F
E H
K
L1
2
2
8
2
5
5
13
9
14
9
12
2
9
14
21
14
17
21
26
5
J14
19
0
0
0
0
1
0
0
00
0 2
1
0
2
4
2
1
00
9
2
00
9
3
11
10
7
50
16
13
42
16
9
00
18
10
51
21
14
00
21
16
22
21
18
44
26
21
00
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Summary of the first compression cycle
Cycle
#
Activity to
shorten
Can be shortened
NIL Days shortened
Cost per day
Cost per
cycle
Total cost
Project duration
0 -- -- -- -- -- -- 5300 28
1 F 2 3 2 150 $ 300 $ 5600 26
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Identifying activities for 2nd compression cycle
Activity A B F H L
Cost/day
- 200$ - 250$ 350$
B : Least cost activity to shorten
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Dur. ES EF FF TF LF
LS
1 6
3
5
3
7 73
5
8
A
B
C
D G
F
E H
K
L1
2
2
8
2
5
5
13
9
14
9
12
2
9
14
21
14
17
21
26
5
J14
19
0
0
0
0
1
0
0
00
0 2
1
0
2
4
2
1
00
9
2
00
9
3
11
10
7
50
16
13
42
16
9
00
18
10
51
21
14
00
21
16
22
21
18
44
26
21
00
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Dur. ES EF FF TF LF
LS
1 6
3
5
3
6 73
5
8
A
B
C
D G
F
E H
K
L1
2
2
8
2
5
5
13
8
13
8
11
2
8
13
20
13
16
20
25
5
J13
18
0
0
0
0
0
0
0
00
0 2
0
0
2
4
2
1
00
9
2
00
8
2
00
9
6
40
16
13
42
13
8
00
17
9
40
20
13
00
20
15
22
20
17
44
25
20
00
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Summary of the 2nd compression cycle
Cycle
#
Activity to
shorten
Can be shortene
d
NIL Days shortene
d
Cost per day
Cost per
cycle
Total cost
Project duratio
n
0 -- -- -- -- -- -- 5300 28
1 F 2 3 2 150 $ 300 $ 5600 26
2 B 3 1 1 200 200 5800 25
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Identifying activities for 3rd compression cycle
Activity A B,C F H L
Cost/day
- 300$ - 250$ 350$
H : Least cost activity to shorten
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Dur. ES EF FF TF LF
LS
1 6
3
5
3
6 73
5
8
A
B
C
D G
F
E H
K
L1
2
2
8
2
5
5
13
8
13
8
11
2
8
13
20
13
16
20
25
5
J13
18
0
0
0
0
0
0
0
00
0 2
0
0
2
4
2
1
00
9
2
00
8
2
00
9
6
40
16
13
42
13
8
00
17
9
40
20
13
00
20
15
22
20
17
44
25
20
00
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Dur. ES EF FF TF LF
LS
1 6
3
5
3
6 63
5
8
A
B
C
D G
F
E H
K
L1
2
2
8
2
5
5
13
8
13
8
11
2
8
13
19
13
16
19
24
5
J13
18
0
0
0
0
0
0
0
00
0 2
0
0
1
3
2
1
00
8
2
00
8
2
00
8
5
30
13
10
22
13
8
00
16
8
30
19
13
00
19
14
11
19
16
33
24
19
00
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Summary of the 3rd compression cycle
Cycle
#
Activity to
shorten
Can be shortene
d
NIL Days shortene
d
Cost per day
Cost per
cycle
Total cost
Project duratio
n
0 -- -- -- -- -- -- 5300 28
1 F 2 3 2 150 $ 300 $ 5600 26
2 B 3 1 1 200 200 5800 25
3 H 1 2 1 250 250 6050 24
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Identifying activities for 4th compression cycle
Activity A B,C F H L
Cost/day
- 300$ - - 350$
B,C : Least cost activities to shorten
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Dur. ES EF FF TF LF
LS
1 6
3
5
3
6 63
5
8
A
B
C
D G
F
E H
K
L1
2
2
8
2
5
5
13
8
13
8
11
2
8
13
19
13
16
19
24
5
J13
18
0
0
0
0
0
0
0
00
0 2
0
0
1
3
2
1
00
8
2
00
8
2
00
8
5
30
13
10
22
13
8
00
16
8
30
19
13
00
19
14
11
19
16
33
24
19
00
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Dur. ES EF FF TF LF
LS
1 4
3
5
3
4 63
5
8
A
B
C
D G
F
E H
K
L1
2
2
6
2
5
5
13
6
11
6
9
2
6
11
17
13
16
17
22
5
J11
16
0
0
0
0
0
2
0
00
0 2
0
0
1
1
2
1
00
6
2
00
6
2
00
6
3
10
11
8
22
11
6
00
14
6
10
17
11
00
17
12
11
17
14
11
22
17
00
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Summary of the 4th compression cycle
Cycle
#
Activity to
shorten
Can be shortene
d
NIL Days shortene
d
Cost per day
Cost per
cycle
Total cost
Project duratio
n
0 -- -- -- -- -- -- 5300 28
1 F 2 3 2 150 $ 300 $ 5600 26
2 B 3 1 1 200 200 5800 25
3 H 1 2 1 250 250 6050 24
4 B,C 2 3 2 300 600 6650 22
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Identifying activities for 5th compression cycle
Activity A B,C F H L
Cost/day
- - - - 350$
L : Least cost activity to shorten
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Dur. ES EF FF TF LF
LS
1 4
3
5
3
4 63
5
8
A
B
C
D G
F
E H
K
L1
2
2
6
2
5
5
13
6
11
6
9
2
6
11
17
13
16
17
22
5
J11
16
0
0
0
0
0
2
0
00
0 2
0
0
1
1
2
1
00
6
2
00
6
2
00
6
3
10
11
8
22
11
6
00
14
6
10
17
11
00
17
12
11
17
14
11
22
17
00
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Dur. ES EF FF TF LF
LS
1 4
3
4
3
4 63
5
8
A
B
C
D G
F
E H
K
L1
2
2
6
2
5
5
13
6
11
6
9
2
6
11
17
13
16
17
21
5
J11
16
0
0
0
0
0
2
0
00
0 2
0
0
1
1
2
1
00
6
2
00
6
2
00
6
3
10
11
8
22
11
6
00
14
6
10
17
11
00
17
12
11
17
14
11
21
17
00
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Summary of the 5th compression cycle
Cycle
#
Activity to
shorten
Can be shortene
d
NIL Days shortene
d
Cost per day
Cost per
cycle
Total cost
Project duratio
n
0 -- -- -- -- -- -- 5300 28
1 F 2 3 2 150 $ 300 $ 5600 26
2 B 3 1 1 200 200 5800 25
3 H 1 2 1 250 250 6050 24
4 B,C 2 3 2 300 600 6650 22
5 L 1 ∞ 1 350 350 7000 21
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Identifying activities for 6th compression cycle
Activity A B,C F H L
Cost/day - - - - -
NO Crashing
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Reports and Reports and presentationspresentations
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INTRODUCTION
Without a doubt, good communication is an essential component of the successful management effort. This means conveying the right information to the right party at the right time and in the right form.
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Characteristics of good communication
1- clarity The information must be clear to the receiving party.
2- simplicity Helps improve understanding. Butting information in briefed sentence/s using a simple language .
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3- AccuracyProfessional communications must be accurate, objective, and up to date.
4- preciseness and relevance to the subjectProviding too much or irrelevant information May be confusing and counterproductive. (example: LDS)
5- legibilityPeople whose handwriting illegible or difficult to read, should type their communications using the computer.
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6- proper support tools Pictures, tables, charts, statistics, etc. They are more helpful and unilingual.
7- proper level of detail The communicator must balance the amount of information in an intelligent way.
8- good organization and formality sorting and organizing the info. to make it easy for the viewer to read, follow and retrieve.
FormalityFormality means following the company’s procedures, including the use of standard forms.
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9- Retrievable and transformable Retrieving info. for live (current) projects may be performed easily by Using the computer commands. The ability to convert and open electronic files and to read the info is extremely important ,so using unknown software should be prohibited .
10- Conformance to industry standardsUsing common language when determining specifications and standards such as ISO,IAI.
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Reports and Presentations
-Both are types of communications that aim at conveying information
-Report should be clear and complete because its printed materials are the only vehicle for conveying information between the person preparing the report and the person receiving it.
- Presentations focus on speakers’ persuasive skills, And the speaker focuses on certain points using oral, visual and written (or printed) tools. Audiences have the opportunity to ask for explanation any point unclear to them.
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Types of presentations
1- contract candidate presentations The main focus of this presentation is to convince the owner (or the decision maker) that the presenter not only can do the job but also can do it better than other candidates, Answering the owner’s question “ why should I hire you?” 2- sales and demonstration presentations a presentation to demonstrate a product given by a representative of a manufacturing or vendor.
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3- project status presentationsa presentation to upper management about a particular project and its status given by the PM or a team member.
4- management presentationsa presentation conducted by the management of a company to its staff to inform them about a new work plan, a new system, a new organization, or something else.
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Presenter’s skills for good presentation
1- Focus on the client’s needsPresenting the product or service in the best way that serves the client /audience.
2- honestythe presenter should be honest and objective at all times, especially with regard to facts and numbers.
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5- eye contact The presenter should speak to the audience not to himself or to his notes.
6- body language Body language and hand and arm gestures are important.
8- Manage time wisely Presentations almost always have time limits. Besides, human beings have limited attention span.
9- have a backup plan
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The power of presentation
To create a good report we should ask ourselves the following questions:
1- does the report include all the information the report user needs?
2- does the report include any un needed information ?
3- is the information clear and well organized?
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4- is the information presented in the required format?
5- can the look of the report be enhanced ?
Remember:1)Computer is still a tool . 2)There is no “one size fits all” .
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Any report (text or graphic) should contain the following information:
1- the name, the address and the logo of the company and department or division.
2- the name of the person preparing the report and supervisor’s approval (if needed).
3- the name and the location of the project.
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4- date
5- title of the report
6- attachments if any.
7- page numbering.
8- legends.
9- definitions of terms, acronyms and abbreviations that may not be known.
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printing reports
After reviewing the final form of the report and before printing it consider the following :
make sure that only the needed activities and information are included .
margins may be slightly reduced to allow more information per page.
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use the “fit to one page” function in the Print menu.
in limited cases you may print o both sides of the paper.
using a smaller or a different (narrower) font may help.
many reports may remain in electronic form and need not be printed.
The scheduler must relate the schedule information to the project manager not only as computer-generated colorful charts ,but in clear language as well.
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SUMMARY REPORTS
Summary report should contain :
The overall situation of the project.
The preceding information as compared with that in the last update.
The new critical path, if it changed.
Cost information (if applicable).
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Any other information that may help the project manager identify trouble spots or makeup for any lost time.
No unnecessary details.
The summary report should not exceed one page.
It should be written in the form of a memorandum.
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Scheduling as Part of the Project Management Effort
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Project manager team
The project manager team consist of: (for large project)
assistant PM
project superintendent
project engineer
scheduler
estimator
safety manager
procurement manager
accountant
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Management team field personal
office personal
it may include teams member who are dedicated exclusively to particular project and others who are assigned to project part time or serve on the project for only temporary period .managing project requires several skills as:
technical skills
managerial skills
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Scheduling and Estimating
Scheduling and estimating are related and their relationships is probably one of the most important relationships in project management These two areas intersected in many ways such as the following eight:
1)the estimator need to know how long the project will last in order to estimate certain cost , particularly overhead
2) Scheduling and Estimating department collaborate to provide information to the procurement department 3) The scheduler estimate the duration of activities with help from the estimating department 4)Many schedules are cost loaded . The cost must be imported from the cost estimate
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5) Earned value management
6) progress payment depend on the schedule of value and the percent complete 7) resource allocation and resource leveling may be cost related ,although they are scheduling issues 8)schedule compression always involves a balance between cost and time
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Construction project involved from many parties
1- General contractor.
2- owner.
3- architect (engineer).
4- subcontractors.
5- government.
6- vendors.
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In order to schedule a project there are two approaches
1- build a master schedule that includes several sub schedule .
2- include all activities in one schedule and assign a responsibility code for each contracting party.
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Time contingency and management options
The scheduler or project manager must include a time contingency representing the non work days.
This time contingency includes two types of non work days.
1- known dates such as a holidays and planned shut down days.
2-Unknown dates.
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Scheduling and change orders
The contractor must then implement the CO in the estimating, scheduling, accounting, and other tracking systems.
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Procurement Management
Procurement is the process of acquiring materials , equipment , and services from external sources for use in a project .
Procurement is a process that usually starts long before the start of the construction process and ends with project completion or project closeout .
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The two objectives of procurement, from the general contractor’s viewpoint, are as follow:
1 -To hire the subcontractor who will actually erect and assemble the project.
2-To purchase the materials called for in the contract.
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Linear Scheduling Linear Scheduling MethodMethod
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Definition A simple diagram to show location and time at which a certain crew will be working on a given operation.
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Characteristics
Shows repetitive nature of the construction.
Progression of work can be seen easily.
Sequence of different work activities can be easily understood .
Have fairly high level of detail.
Can be developed and prepared in a shorter time period than other formats.
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Advantages of LSM
Provides more information concerning the planned method of const. than a bar chart.
In certain types of projects, LSM offers some advantages over the network approach.
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Line of Balance Technique
LSM has relationships to the line of balance (LOB) technique, developed by US. Navy in the early 1950s.
First applied to industrial manufacturing and production control.
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Three diagrams are used in LOB
1. Production DiagramShows the relationships of the assembly operations for a single unit. Similar to AOA, except that it shows only one unit of production.
2. Objective DiagramUsed to plot the planned or actual number of units produced vs. time. LSM diagram resembles this diagram.
3. Progress Diagram Shows the number of units for which each of the subassembly operations has been completed.
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Difference between Objective Diagram and LSM
O.D. is used to schedule or record the cumulative events of unit completion.
LSM is used to plan or record progress on multiple activities that are moving continuously in sequence along the length of a single project.
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Implementation of LSM
Can be used for continuous activities rather than discrete activities.
Transportation projects; highway const., highway resurfacing and maintenance, airport runway const. and resurfacing, tunnels, mass transit systems, pipelines, railroads.
High-rise building construction.
Repetitive building units.
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Elements of the LSM
Axis Parameters
Location
Measure of progress.
In high-rises and housing const., measures may be stories, floors, subdivisions, apartments, housing units.
In Transportation projects, distance (ft. or mile can be used, but division by stations (100ft.) is common) is general.
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Time
Hours, days, week, or month - depends on the total project time and level of detail desired in the schedule.
Preferable to prepare the schedule based on working days and convert to calendar days only at the end.
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Activity Production Rates
Obtained by the usual estimating methods as a function of the activity, equip. characteristics, labor, and job conditions.
The initial rate should be associated with the min. direct cost of accomplishing the single activity.
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Activity Interruption and Restraint
Prod. rate may vary with locations or time periods.
Progress may be interrupted intentionally and restraints may occur between activities due to limited equip. or crews.
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Buffers
When const. activities progress continuously in a chain, some spacing between activities is required.
This spacing serves as a buffer and may require distance or time interval between activities.
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Activity Intervals
Used to describe the period of time between the start and finish of an activity at a particular location.
Intervals can be indicated by a broad line, two narrow lines, etc.
Monitoring Progress.
Working calendar can be marked with a moving symbol or a line, tape, etc.
vertically across the diagram.
Progress on individual activities would be marked by location rather than time.
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Project Time Optimization
The total project time may be such that indirect costs and liquidated damages assessed are more costly than the expense of accelerating certain activities.
Cost-duration analysis can be used to minimize the total cost, as follows :
Identify all activities that can be accelerated or
decelerated.
Among the above, consider only those that are
at a buffer limitation at both the start and the
finish of the activity.
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Of these, select the one activity with the
lowest cost slope associated with
acceleration (or deceleration).
Accelerate (or deceleration) the activity
rate of production the maximum feasible
amount.
Repeat the above steps successively until
the optimum project cost and associated
duration are obtained.
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Discrete Activities
Discrete are best scheduled by other methods. Once the duration is determined by network analysis, it can be scheduled on the LSM diagram and coordinated with the linear activities.
Seasonal Adjustments
When developing LSM, appropriate adjustments can be made for seasonal effect on construction
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Project Progress and Resource Management
Project progress is often estimated by the S-curve with bar chart development.
In LSM, the determination of activity progress is facilitated and made more rigorous.
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LSM Schedule
4
3
2
1
2 4 6 8 10 12 14 16 18 20 22 24
Excav
ate Fnd
s
F & P Fnds & Slab
Frame
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LSM Schedule with Brickwork
4
3
2
1
2 4 6 8 10 12 14 16 1820 22 24
Excav
ate Fnd
s
F & P Fnds & Slab
Frame
Brickwork
Buffer
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Four-unit Duplex I-J Fragnet
2EXC FNDSBLDG 1
7F&P FNDS& SLABBLDG 1
8FRAMEBLDG 1
2EXC FNDSBLDG 2
7F&P FNDS& SLABBLDG 2
8FRAMEBLDG 2
2EXC FNDSBLDG 3
7F&P FNDS& SLABBLDG 3
8FRAMEBLDG 3
2EXC FNDSBLDG 4
7F&P FNDS& SLABBLDG 4
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4
3
2
1
2 4 6 8 10 12 14 16 18
Excav
ate Fou
ndati
ons
Days
Dup
lex
Num
ber
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Construction Delay Construction Delay ClaimsClaims
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DEFINITIONS
Delay: An event or a condition that results in finishing the project later than stipulated in the contract .
Claim: a request from one contracting party to another party for additional compensation ,a time extension , or both .
Note: a claim is not always a negative action ,nor does it automatically indicate a confrontation .
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Delay claims and change order
A CO may be initiated at the request of the Owner ,Contractor , Sub-Contractor.
They must submit a request for quotation (RFQ) to initiate their CO , And this request could be an owner decision or a “what if ” inquiry , the quotation may includes a cost estimate and the impact on the schedule .
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To minimize the number of CO’s Owners should define the scope of the project and select a competent designer .
Many projects suffer from scope-creep syndrome , in which CO’s keep adding to the project budget and put it at levels far beyond what the owner originally planned.
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Reasons for delay claims
1- Differing site conditions
2- design errors or omissions
3- changes in Owner’s Requirements
4- Unusually adverse weather
5- Miscellaneous factors
6- Force Majeure
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Changes in owner’s requirements
May constitute a change in the contract and provide a foundation for Cos. Owners are always encouraged to know exactly what the want within their budgetary limits.
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Force Majeure (superior force)
In the context of construction projects, this term usually involves three important elements :
1- Something that is superior, overwhelming, or overpowering (i.e, can not be prevented)
2- Something that is unexpected or cannot be reasonably anticipated or controlled.
3- Something that has a destructive or disruptive effect on the construction process.
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Types of delays resulting in claims
1- Excusable delay.
2- Non excusable delay.
3- Concurrent delays.
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Delay claims prevention
1- Baseline schedules that don’t show logic.
2- baseline schedule with dates rather than logic.
3- Overuse of constrains.
4- Erasing footprints.
5- unrealistic baseline schedule.
6- schedule with logic errors.
7- skipping periodic updates.
8- lack of proper documentation.
9- lack of a reasonable time contingency.
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Communication means conveying information from one
party to other parties across the organization
Documentation means saving the information in an
organized manner for possible future retrieval.
Communication and documentation
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Communications and documentation must both contain:
Clear information.
Provide the proper a mount oh details.
Be stored efficiently, so that the information can be retrieved easily .
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1- The project baseline schedule that the owner accepted
2- Periodic schedule updates
3- Change orders
4- Job diary
5- Correspondence with the home office
6- Submittal records, such as shop drawings and material samples.
We must document these information
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7- Records of any transmittals
8- Meeting minutes
9- Procurement records
10- Government records
11- Records of payment
12- Project manager’s daily log
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Logbook should include daily information such as the following :
•Weather condition: temperature, wind.
•Work performance during that day.
•The number of workers on-site.
•Equipment on-site and its condition.
•Any accidents that occurred on-site
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Methods of resolving claims
Negotiation
The most direct method for resolving any type of construction claim.
Requires certain skills that reduce the gap between the negotiation parties.
The objective: is to reach a solution that might be acceptable to both parties.
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Mediation When negotiation does not work, either because
of lack of trust or a lack of skills, mediation may be an option.
The mediator may be an individual or a team. Dispute review boards
The owner and the contractor select an independent neutral panel with construction experience when the contract is signed .
Rather than waiting until the end of project to settle claims, (DRBs) resolve disputes as they arise.
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Arbitration It is usually a formal process performed by an
independent professional arbitrator.
Arbitration is voluntary.
Arbitration does not require the use of lawyers
Litigation When none of the previous work and parties
can not reach a settlement, the complaining party uses the other party in a court of law.
Construction litigation is usually complicated lengthy, and expensive.
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Method of Schedule Analysis
As- build schedule As – planned schedule Comparison schedule
Accelerated schedule
Recovery schedule
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As-Built Schedule
The as-built schedule should reflect what actually happened in the filed.
Activities are plotted by their real start and real finish , disregarding any logic
Contain real budget and real resources
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As – planned schedule
The as-planned schedule describes the manners in which the contractor in tended to built the project.
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Comparison schedule
revised to incorporate any claimed delays .
for delay claim the contractor submits two schedules.
without the causative factors
with the causative factors
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Accelerated schedule
Submitted by the contractor.
The project can finish by the contractor finish date.
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Safety Safety & Health Management & Health Management
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Introduction
One of the most important factors that should be taken in consideration in the site, (from engineering point view), is the safety and health management.
Safety and health management; is considered as a progress measure of the engineering and construction companies.
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Safety: The condition or state of being safe;
freedom from danger or hazard; exemption from
hurt, injury, or loss.
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Hazard: A condition with the potential of causing or contributing to an accident or
illness.
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Rules in construction area under safety outline:
1 )knowing hazards and how to avoid them.
this mean know Construction Activity /
Corresponding Hazard Identification and activity
classification with respect to hazard as shown in
the following table.
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• Heavy Equipment Operation -Class II• Material Handling -Class II • Temporary & Permanent Electricity -Class III • Cranes & Critical Lifts -Class III • Slings & Lifting Gear -Class III • Welding, Cutting & Brazing -Class III • Hand/Power Tools -Class II • Sanitation & Housekeeping -Class I • Scaffolding/Ladders -Class III • Manholes Excavations, Pits, Trenching & Shoring -Class III • Camp, Site Office & Lay down Yard -Class II • Over head Obstruction -Class III • Road Construction & Re-routing of Existing Roads -Class I • Concrete, Concrete Forms & Shoring -Class I • Sandblasting -Class II • Thrust Boring -Class I • Hot Taps -Class I • Personal Safety -Class I • Paints & Coatings -Class I • Piling Operations -Class II • Demolition -Class III • Mechanical Equipment -Class II • Chemical -Class III • Liquefied Petroleum Gas (LPG) -Class III • Fuel -Class III • Site Operations & Hydrocarbon -Class III
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Rules in construction area under safety outline: (cont.)
•2 )use Personal Protective Equipments (PPE).
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Rules in construction area under safety outline: (cont.)
3 )how to deal with emergency situations and what are the proper steps.
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Rules in construction area under safety outline: (cont.)
•4 )follow the instructions carefully.
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Occupational Safety & Health Administration
An organization that interests in achieving and applying safety factors in the construction field .
It deals with the identification and control of environmental and personal hazards in the work place.
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OBJECTIVE OF S&HMANAGEMENT
Minimize losses –Avoid injuries
–Avoid OSHA fines –Avoid litigation
Development and implementation of S&H program is key to good management
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ELEMENTS OF S&H PROGRAMS
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Top management commitment Goal setting and planning Organization & administration Project safety rules Substance abuse program Emergency management Safety orientation & training Accident investigation &
recordkeeping Safety budget Safety in contracts Safety program evaluation TQM integration.
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UNIQUE FACTORS INCONSTRUCTION AFFECTING S&H
431
Large but diverse and fragmented industry
every job is unique with numerous complex tasks
Labour intensive work involving large forces
Transient workforce which is difficult to train.
Complex contractual arrangements leading to multi-employer projects
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HOW SAFETY SAVES MONEY
432
Economic impacts
Direct and indirect accident costs
Workers compensation and EMR
Accident cost accounting
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ECONOMIC IMPACTS OF S&H
433
Myth: There is a trade-off between safety
and cost and productivity
Truth: Safety saves money
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COSTS ASSOCIATED WITH S&H
434
A. Direct (insured) costs of accidents, injuries and illnesses
B. Indirect (hidden) costs – uninsured
C. Costs associated with company s&h programs
-Resource allocations for: Safety director/coordinator Equipment and supplies Time (meetings, inspections, etc.)
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DIRECT COSTS
435
Workers compensation insurance premiums
paid by contractor (mainly for medical bills)
Liability insurance costs
Property related insurance costs.
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INDIRECT (HIDDEN) COSTS436
Transportation for first aid/medical treatment Delays resulting from accident Wages paid to injured worker for time not worked Loss of crew efficiency Training new/substitute worker. Clean-up, equip. repair, stand-by Rescheduling work Post accident extra safety supervision OSHA and civil fines Legal fees Cost of administrative time for investigations and reports.
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BASIC AIM OF THE OSHA
437
To ensure, so far as possible, every working person safe and healthful conditions in the workplace, which must be free from recognized
hazards likely to cause death or serious physical
harm.
Applicable to all employers – Records of illness/injury must be kept by employers with more than ten employees.
– Not applicable to self-employed and work places covered by other federal agencies
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SUMMARY
438
Accidents can be tragic and costly.
Safety and health programs prevent injuries and fatalities, and save money
Effective program organization and implementation will help achieve OSHA compliance and lead to success at corporate and project levels.
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remember
If it is unsafe, just don’t do it... If it is dangerous, always avoid it
for all we know
Safety is everyone‘s responsibility
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Good LuckTHE END
