Lcc a Manual

8/12/2019 Lcc a Manual

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February 5, 2008

LIFE-CYCLE MANAGEMENT OFINTERLOCKING CONCRETE PAVEMENT

By:

Applied Research Associates, Inc.5401 Eglinton Avenue West, Suite 204

Toronto, Ontario M9C 5K6Telephone: (416) 621-9555 Facsimile: (416) 621-4917

Web: www.ara.com/transportation


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TABLE OF CONTENTS

1.0 Introduction ........................................................................................................................ 21.1 Life-Cycle Costing......................................................................................................... 21.2 Scope.............................................................................................................................. 2

2.0 Initial Design Life of Interlocking Concrete Pavements .................................................... 32.1 Data Source .................................................................................................................... 32.2 Level of Service ............................................................................................................. 4

3.0 Maintenance and Rehabilitation Needs for Interlocking Concrete Block Pavements........ 53.1 Initial Interlocking Concrete Block Pavement Design................................................... 53.2 Estimating Activity Costs .............................................................................................. 63.3 Maintenance and Rehabilitation Plan............................................................................. 6

4.0 Comparable FLEXIBLE and Rigid Structure and M&R Program..................................... 74.1 Flexible Pavement Structure .......................................................................................... 8

4.2 Rigid Pavement Structure .............................................................................................. 9

5.0 Estimating Total Life-Cycle Cost....................................................................................... 95.1 Calculation of Net Present Value................................................................................. 105.2 Pavement Residual Value ............................................................................................ 105.3 Life-Cycle Cost (LCC)................................................................................................. 10

6.0 Conclusions ...................................................................................................................... 12

7.0 References ........................................................................................................................ 12

LIST OF APPENDICES

APPENDIX A Example Life-Cycle Cost Analyses


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1.0 INTRODUCTIONLife-cycle costing has become an essential component of any modern infrastructure design. It has longbeen realized that maintenance and rehabilitation costs, not just the immediate initial construction costsshould be considered when evaluating similar pavement alternatives. Applied Research Associates, Inc.(ARA) was retained by the Interlocking Concrete Pavement Institute (ICPI) to develop some guidelines

and a spreadsheet model to develop realistic life-cycle cost procedures for flexible, rigid and interlockingconcrete block pavements for low traffic volume pavements.

As a part of the development of pavement design and management tools for the ICPI, ARA has developedappropriate pavement design, maintenance and rehabilitation (M&R) procedures to document the life-cycle costs (LCC) of interlocking concrete block pavements. These tools and procedures can be used todocument the life-cycle cost benefits of interlocking concrete block pavements compared to flexible andrigid pavements.

1.1 Life-Cycle CostingThe FHWA [1] describes LCCA as an analysis technique that builds on the well-founded principles ofeconomic analysis to evaluate the over-all-long-term economic efficiency between competing alternativeinvestment options. The comparison of life-cycle costs has become standard to not only comparedifferent pavement types, but also evaluate different feasible rehabilitation plans over the service life of apavement.

Municipal pavements are typically designed for an initial service life of between 10 and 20 years. At theend of the service life, some form of rehabilitation action such as a mill and overlay for flexiblepavements, concrete pavement restoration treatment (e.g. slab repairs, crack sealing, etc.) for rigidpavements or removal and resetting of interlocking concrete blocks for interlocking concrete pavements(ICP) is completed.

The actual service life of both the initial pavement construction and rehabilitation treatment is dependanton a variety of factors including type and composition of the traffic, timeliness of maintenance treatments,

and environmental factors such as temperature and precipitation. In order to develop comparative costestimates to determine the whole life cost of the different pavement types, it is necessary to know thetiming, type and quantities of repairs and their service life. The service life of a pavement is defined asthe time between initial construction and the time when the pavement reaches a minimum acceptablelevel of service. Life-cycle costing is a technique that quantifies all of the costs necessary to constructand maintain a pavement over a set analysis period, typically between 25 and 50 years. Future costs arediscounted to todays dollars by using a discount rate which takes inflation and interest rates in account todetermine the net present value of future costs. By comparing the total life-cycle cost of two or morepavement options, it is possible to make informed decisions as to the best pavement alternative for aparticular application.

1.2 ScopeThe development of a life-cycle cost tool is important to allow flexibility when analyzing a variety ofpavement type options. To evaluate the life-cycle cost it is important to evaluate the costs in terms ofseveral key parameters:

Life-cycle costing parameterso Analysis periodo Discount rate

Initial pavement costs


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o Designo Construction

Maintenance and rehabilitation activitieso Typeso Timingo Cost

All of these factors should be considered for interlocking concrete, flexible, and rigid pavements. AMicrosoftExcel based tool has been developed to assist agencies and practitioners in evaluating the totalcosts of the various pavement alternatives.

2.0 INITIAL DESIGN LIFE OF INTERLOCKING CONCRETE PAVEMENTSThe initial design and construction of pavements is a critical factor in the life-cycle cost evaluationprocedure. A pavement built for its appropriate traffic and environmental conditions will have areasonable service life and provide a functional and safe platform for the travelling public. The servicelife of a pavement is usually established during the initial design considering the subgrade, pavementlayer materials and their thicknesses and the anticipated traffic that will utilize the roadway. This service

life can be somewhat variable depending on the environmental and loading conditions to which thepavement is exposed during its service life. By monitoring and rating the pavement performance over itsservice life using standard pavement management tools such as the pavement condition index (PCI), it ispossible to establish typical pavement performance curves for the pavement [2].

To determine the expected life of a pavement, the measured condition, along with a minimum acceptablelevel of service is used. The typical path of deterioration is monitored over the life of the pavement untilthe pavement reaches the typical terminal level of serviceability, at which point very few field data pointsare available.

To generate the deterioration path, several possible techniques can be used. A common statisticaltechnique called regression consists of selecting an appropriate form for modelling pavement condition

deterioration and using the method of least squares to determine the best fit model. This methodcalculates the best-fitting line for the observed data by minimizing the sum of the squares of the verticaldeviations from each data point to the line (if a point lies on the fitted line exactly, then its verticaldeviation is 0).

2.1 Data SourceThe pavement performance data was collected from 48 interlocking concrete block pavement roadwayslocated in 7 cities across North America. The detailed pavement condition assessments were completedbased on the draft procedure in the Standard Practice for Pavement Condition Index Surveys for ConcreteBlock Pavement[2]. The survey procedure is modelled on the U.S. Army Corps of EngineersMicroPAVER distress guide as published by ASTM [3].

The surveys were completed in the summer and fall of 2007 on interlocking concrete block pavements inthe following cities:

Baltimore, MD Boston, MA Hamilton, ON North Bay, ON San Antonio, TX


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Syracuse, NY Vancouver, BC

To compare the various pavements and their stage of deterioration, construction history was determinedthrough local knowledge of the various projects. The construction history included the initialconstruction date as well as any information regarding maintenance and rehabilitation treatments. The

pavement age was then used in conjunction with the current pavement condition to develop adeterministic regression model.

The results of the performance modelling is shown in Figure 1. From this data it can be seen that a largedegree of variability is measured in the field. This type of variability is common among all pavementtypes and reflects many factors, other than age, that affect the service life of the pavement. A generaltrend can be seen from the regression indicating the typical path of deterioration.

0

10

20

30

40

50

60

70

80

90

100

0 5 10 15 20 25

Age (Years)

PavementConditionInde

x

Figure 1. Pavement Condition Index and General Performance Model for Interlocking ConcreteBlock Pavements

The path of deterioration shown in Figure 1, shows that a typical interlocking concrete brick pavementwill show a relatively slow deterioration in the first 8 years of service.

2.2

Level of ServiceThe minimum acceptable level of service is an important decision that must be made by a designer. Themaximum state of deterioration that a pavement is expected to reach can greatly change the service life.It many cases however, the service level of a pavement must be maintained at a high level due to thetypes of use it will be exposed to.

The level of service can be described in terms of a variety of types of condition indicators such asstructural capacity, ride quality, or visual distress. On most low volume roads, the visual condition istypically used because it can represent the other factors in terms of an overall rating. With the relatively


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low operating speed of most low volume pavements the impact of other functional performance factors isreduced. A typical rating scale for the visual condition in terms of the PCI is show in Figure 2.

Based on the condition descriptions in Figure 2 and the level of service measured during the fieldinspections, a typical rating of a PCI of 60 is recommended as a minimum level of service. Once apavement passes this level, substantial repairs throughout a section are likely required to bring the

pavement up to an excellent condition level. Using a typical minimum serviceability trigger value PCI of60, this data would indicate a typical ICP service life of 20 years. It was noted that the variabilityincreases significantly after 8 years into the service life. The data also shows a group of pavementsections with relatively low PCI values (between 40 and 60) which do not seem to be grouped with theremainder of the pavement sections. If these sections were removed from the population, theperformance curve would cross the PCI of 60 trigger value closer to 30 years.

Excellent100

85

70

55

40

PCI Rating

Failed

Very Good

GoodFair

Poor

Very Poor25

0

10

Excellent100

85

70

55

40

PCI Rating

Failed

Very Good

GoodFair

Poor

Very Poor25

0

10

Figure 2. Level of Service Based on Pavement Condition Index

It is possible however to consider reduced level of service requirements for very low volume roads orparking areas. Due to the low speed of vehicles and the limited use, consideration could be given to

setting the minimum acceptable PCI at 50 for these types of pavements.

3.0 MAINTENANCE AND REHABILITATION NEEDS FOR INTERLOCKING CONCRETEBLOCK PAVEMENTS

There is little doubt as to the importance of the initial construction cost of a pavement. However the on-going maintenance and rehabilitation costs can be a significant cost over the entire life-cycle of apavement. To account for these costs, pavement maintenance of rehabilitation activities are typicallyscheduled to occur at various times to maintain and improve the serviceability of the pavement. Thetiming of the activities, in conjunction with the cost to perform the activities is then combined to estimatethe total life-cycle cost.

3.1 Initial Interlocking Concrete Block Pavement DesignThe cost to design and construct the initial pavement structure is typically the largest expense over thelife-cycle. The initial pavement design of an interlocking concrete block pavement is very dependent onmany factors such as traffic level, environment, and materials used. For the purpose of the life-cyclecosting, a typical structure, based on an example from the ASCE Draft Pre-Standard for the StructuralDesign of Interlocking Concrete Pavement [4], has been used as an example:


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Design Details

Design Traffic 300,000 ESALsDrainage Type FairSubgrade Type CL (Mr= 20 MPa)

Concrete pavers (with sand filled joints) 80 mm thicknessBedding sand 25 mm thicknessGranular base 150 mm thicknessGranular subbase 295 mm thickness

This is adequate for the types of traffic typically supported by a municipal roadway.

3.2 Estimating Activity CostsOne of the key components for the evaluation of total costs over the pavement life-cycle is the estimationof maintenance and rehabilitation costs. This is typically accomplished by reviewing the potentialactivities that will occur through out the service life of a pavement, their frequency and costs.

The maintenance and rehabilitation costs used in the analysis are based on current dollars. Adjustmentsdue to inflation and discounting are taken into account later during the life-cycle cost analysis. The unitcosts represent the whole cost to complete the maintenance and rehabilitation activity, including labor,equipment and materials. An example of the estimated unit costs for the expected activities on theinterlocking concrete block pavements are given in Table 1. It must be recognized that unit cost can varysignificantly depending on location, size of the project, availability of materials and contractors, etc.

Table 1. Unit Costs for Mainenance and Rehabilitation

Activity Unit Cost ($) Unit

Bedding Sand and Paver Installation $40.00 m2

Granular Base $13.00 tonne

Granular Subbase $8.50 tonneReplace Cracked Pavers $40.00 m2

Replace Worn/Rutted Pavers (wheelpath) $60.00 m2

3.3 Maintenance and Rehabilitation PlanThe maintenance and rehabilitation (M&R) plan for the block pavements is set out as a typical scenario tomaintain the pavement in a cost effective and serviceable manner and reflects maintenance andrehabilitation activities and timing. These activities are typically include mill and overlay for flexiblepavement, concrete pavement restoration (e.g. slab repairs, crack sealing, etc.) for rigid pavement andreplacement and resetting of interlocking concrete blocks for an ICP. The typical life-cycle and timing ofmaintenance and rehabilitation treatments is illustrated in Figure 3.


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Time (Years)

Preventive Maint.

RoutineMaint.

Rehabilitation

Reconstruction

Good

Poor

Time (Years)

Preventive Maint.

RoutineMaint.

Rehabilitation

Reconstruction

Good

Poor

Figure 3. Timing of Maintenance and Rehabilitation Activities

A typical plan for maintenance and rehabilitation expected for an interlocking concrete pavement isoutlined in Table 2. This plan should be evaluated on a project by project basis before implementation inthe field to ensure the correct timing of activities.

Table 2. Unit Costs for Maintenance and Rehabilitation

Year Activity Quantity

(%)8 Replace Cracked Pavers 2

20 Replace Worn/Rutted Pavers (wheelpath) 5

28 Replace Cracked Pavers 2

35 Replace Worn/Rutted Pavers (wheelpath) 5

4.0 COMPARABLE FLEXIBLE AND RIGID STRUCTURE AND M&R PROGRAMThe key benefit of a life-cycle cost analysis is the ability to compare multiple pavement structures thathave different initial cross-section and hence different maintenance strategies. Flexible and rigidpavement designs have been developed based on the matching geometric and traffic conditions to the

interlocking concrete block pavement example. Unit costs for the flexible and rigid pavement structurescan be found in Table 3 [5].


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Table 3. Unit Costs for Mainenance and Rehabilitation

Activity Unit Cost ($) Unit

Doweled Jointed Concrete Pavement (200 mm) 60.00 m2

Plain Jointed Concrete Pavement (200 mm) 45.00 m2

Asphalt Concrete (Surface) 95.00 tonne

Asphalt Concrete (Base) 85.00 tonneGranular Base 13.00 tonne

Granular Subbase 8.50 tonne

Rout and Seal Crack 2.00 m

Reseal Joints 2.00 m

Asphalt Patching 7.00 m2

Mill and Overlay Pavement 86.00 tonne

Concrete Pavement Restoration 160.00 m2

4.1 Flexible Pavement StructureFlexible pavement structures are typically composed of an asphalt concrete surface over granular base andsubbase combination. A typical flexible pavement structure, based on the 1993 AASHTO Design Guide,with a comparable traffic and subgrade condition to the interlocking concrete block pavement example is:

Design Details

Design Traffic 300,000 ESALsDrainage Type FairSubgrade Type CL (Mr= 20 MPa)SNDesign97.4 mm

Asphalt Concrete 100 mm thickness

Granular base 150 mm thickness

Granular subbase 400 mm thickness

This structure is a pretty typical for a municipal pavement. A typical maintenance and rehabilitation planfor this flexible pavement structure is given in Table 4.

Table 4. Flexible Pavement Mainenance and Rehabilitation Plan

Year Activity Quantity(%)

4 Rout and Seal Cracks 5

8 Machine Patching 515 Mill and Overlay (50 mm) 100


22 Machine Patching 10

25 Mill and Overlay (90 mm) 100


30 Machine Patching 10

37 Mill and Overlay (50 mm) 100


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4.2 Rigid Pavement StructureRigid pavement structures are typically composed of a Portland Cement Concrete (PCC) layer over agranular base material. A typical PCC design assuming jointed plain concrete pavement is providedbelow:

Design Details

Design Traffic 300,000 ESALsDrainage Type FairSubgrade Type CL (K = 51.5 MPa/m)DDesign 200 mm (minimum recommended PCC thickness)

PCC Pavement 200 mm thickness

Granular subbase 150 mm thickness

Table 5. Rigid Pavement Mainenance and Rehabilitation Plan

Year Activity Quantity(%)

5 Reseal Joints 5

15 Minor Concrete Pavement Repair 2

18 Reseal Joints 15

25 Major Concrete Pavement Repair 5

30 Reseal Joints 5

40 Minor Concrete Pavement Repair 2

43 Reseal Joints 15

5.0 ESTIMATING TOTAL LIFE-CYCLE COSTThe estimation of the total life-cycle cost is an aggregate of the initial and the maintenance andrehabilitation costs for each alternative. The inputs used for evaluating the total life-cycle cost areslightly more complicated. This process is handled by a spreadsheet tool to provide accurate andconsistent numbers.

The total life-cycle combines many factors for all three pavement type scenarios to determine the lowestlife-cycle cost. The required inputs include:

General inputso Analysis periodo Discount rateo Site description/dimensions

Interlocking concrete block pavementso Unit costso Initial pavement layer thicknesso Maintenance and rehabilitation plan and quantities

Flexible pavementso Unit costs


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o Initial pavement layer thicknesso Maintenance and rehabilitation plan and quantities

Rigid pavementso Unit costso Initial pavement layer thicknesso Maintenance and rehabilitation plan and quantities

5.1 Calculation of Net Present ValueThe costs distributed over the pavement are typically translated into a Net Present Value (NPV). TheNPV represents the total cost today that would be required, accounting for the interest and inflation interms of the discount rate. The NPV of all activities are summed up to estimate the total maintenance andrehabilitation cost.

( )( ) +

=i

Age

i

RateDiscount

CostRM

1

&CostR&MTotal

The discount rate used in the analysis represents the potential interest rate that can be achieved. The

discount rate typically reflects the social discount rate for public sector projects and is dependent on manyfactors such as current economic environment, market risk, and many other potential factors.

5.2 Pavement Residual ValueTo ensure fair comparison of the alternatives, residual value of any unused pavement rehabilitationactivity at the end of the analysis period must be included in the life-cycle cost analysis. The residualvalue is estimated by the straight line depreciation of the last capital activity cost. The Prorated Lifemethod is used in the LCCA procedure to estimate the residual value. The recoverable cost is estimatedby dividing the remaining life of the last rehabilitation treatment, by the expected life of the treatment.

=

LifeService

AgeActivityLifeServiceCostRM&ValueResidual

To determine the salvage value, the last major rehabilitation activity is used. Based on the year ofimplementation of the last rehabilitation, the expected service life (from the Unit Costs table) and theactivity cost, a proportion of the initial cost is determined. The residual value, at the end of the designperiod, is then converted in to a net present value. The residual value is then subtracted from the othercosts.

5.3 Life-Cycle Cost (LCC)The total cost to construct and maintain each design option is the key focus of a LCCA. To accomplishthis, the total sum of all costs, in equivalent NPV is required. The total cost is thus calculated as:

LCC= Initial Cost + Total M&R Cost Residual Value

This value can then be used to benchmark other potential options and determine which is the most costeffective.

A worked example of total life-cycle costs using the above data and procedures is provided inAppendix A. A summary of the overall results is provided in Table 6.


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Table 6. Summary of Present Worth of Example Life-Cycle Cost Analysis(Design Traffic = 300,000 ESALs)

Pavement Type Initial Cost ($) Maintenance andRehabilitation Costs ($)

Total Present Worthof Costs ($)

Asphalt Concrete 252,694 112,465 365,158

Concrete 482,175 44,094 526,269ICP 373,549 20,012 393,561

The initial and life-cycle costs were recalculated for equivalent pavement structures with a design trafficof 5 million ESALs. The results of the analysis are provided in Table 7 and on Figure 4. This analysisalso includes an ICP design incorporating an asphalt treated base over a granular subbase.

Table 7. Summary of Present Worth of Example Life-Cycle Cost Analysis(Design Traffic = 5,000,000 ESALs)

Pavement Type Initial Cost ($) Maintenance and

Rehabilitation Costs ($)

Total Present Worth

of Costs ($)Asphalt Concrete 368,400 112,465 480,865

Concrete 519,675 44,094 563,769

ICP Granular Base 451,388 20,012 471,400

ICP Asphalt Base 465,025 15,470 480,495

Life-Cycle Cost Comparison

420,000

440,000

460,000

480,000

500,000

520,000

540,000

560,000

580,000

Asphalt Concrete Concrete ICP Granular Base ICP Asphalt Base

Pavement Type

Life-CycleCost/2lane-km

Figure 4. Total Life-Cycle Cost Comparison for 5 Million ESAL Pavement Designs


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6.0 CONCLUSIONSThe development of a Life-Cycle Cost tool allows for the examination of various design options todetermine which pavement type is the most cost effective over the total life-cycle of the pavement. TheLCCA tool developed for the ICPI can be customized on a site by site basis to allow for specificpavement details and costs to be used.

7.0 REFERENCES1. Walls, James III and Michael R. Smith. Life-Cycle cost Analysis in Pavement Design Interim

Technical Bulletin. FHWA Report FHWA-SA-98-079, September 1998.

2. Interlocking Concrete Pavement Institute, Standard Practice for Pavement Condition Index Surveysfor Concrete Block Pavement, Washington, D.C., December 2007.

3. American Society for Testing Materials,ASTM D6433-07 Standard Practice for Roads and ParkingLots Pavement Condition Index Surveys, ASTM, Washington, D.C., 2003.

4. Smith, David R.. Draft Pre-Standard, Structural Design of Interlocking Concrete Pavement.American Society of Civil Engineers, Draft 07/16/07.

5. Applied Research Associates, Inc.,Estimation of the Representative Annualized Capital andMaintenance Costs of Roads by Functional Class, March 31, 2006,http://www.tc.gc.ca/pol/en/aca/fci/menu.htm.


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A.1

APPENDIX A

EXAMPLE LIFE-CYCLE COST ANALYSES


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SI Urban Pave

US Customary Parking Lot

Project Description Denver Examples

Location Denver, Colorado

Type of Project Urban Pavement Design

Analysis Period 40

Discount Rate 4.0

Construction Year 2008

Measurement Units SI

LIFE-CYCLE COST ANALYSIS

LIFE CYCLE COST ANALYSIS SPREADSHEET

BASIC INPUT PARAMETERS

INTERLOCKING CONCRETE PAVEMENT INSTITUTE

Life-Cycle Cost Comparison

420,000

440,000

460,000

480,000

500,000

520,000

540,000

560,000

580,000

Asphalt Concrete Concrete ICP Granular Base ICP Asphalt Base

Pavement Type

Life-CycleCost/2lane-km


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No. Description Mean Price St. Deviation Unit

1 Bedding Sand and Paver Installation $40.00 $4.00 Sq. m

2 Granular Base $13.00 $2.00 Tonne

3 Granular Subbase $8.50 $1.00 Tonne4 Replace Cracked Pavers $40.00 $4.00 Sq. m

5 Replace Worn/Rutted Pavers (Wheelpath) $60.00 $6.00 Sq. m

6 Doweled Jointed Concrete Pavement $60.00 $8.00 Sq. m

7 Plain Jointed Concrete Pavement $45.00 $4.50 Sq. m

8 Asphalt Concrete Surface $95.00 $8.00 Tonne

9 Asphalt Concrete Base $85.00 $7.00 Tonne

10 Rout and Seal Cracks $2.00 $0.50 m

11 Reseal Joints $2.00 $0.50 m

12 Patching (%) $7.00 $1.00 Sq. m

13 Mill and Overlay Asphalt Pavement $86.00 $8.60 Tonne

14 Concrete Pavement Restoration $160.00 $16.00 Sq. m

15

Denver Examples

LIST OF CONSTRUCTION ITEMS


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Project Definitions:

Length of Section: 1000 m Analysis Period: 40.0

Lane Width: 3.75 m Discount Rate: 4.0

Number of Lanes: 2 m Initial Year of Construction: 2008

Total Pavement Area: 7,500 Sq. m

YEAR AMOUNT QTY. UNITUNIT

PRICEST DEV COST

PRESENT

WORTH

INITIAL CONSTRUCTION

0 7500 7500 Sq. m $40.00 $4.00 $300,000 $300,000

0 150 2475 Tonne $13.00 $2.00 $32,175 $32,175

0 295 4867.5 Tonne $8.50 $1.00 $41,374 $41,374

MAINTENANCE AND REHABILITATION ACTIVITIES


PRICEST DEV COST

PRESENT

WORTH

8 150 150 Sq. m $40.00 $4.00 $6,000 $4,384

20 375 375 Sq. m $60.00 $6.00 $22,500 $10,269

28 150 150 Sq. m $40.00 $4.00 $6,000 $2,001

35 375 375 Sq. m $60.00 $6.00 $22,500 $5,702

Granular Subbase

Example Project, Gainesville, Florida

LIFE CYCLE COST ANALYSIS

INTERLOCKING CONCRETE PAVEMENT

CONSTRUCTION ITEM

Bedding Sand and Paver Installation

Granular Base

MAINTENACE ACTIVITY

Replace Cracked Pavers

Replace Worn/Rutted Pavers (Wheelpath)

Replace Cracked Pavers

Replace Worn/Rutted Pavers (Wheelpath)


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PRICEST DEV COST

PRESENT

WORTH




CONSTRUCTION ITEM

TOTAL COST OF NEW CONSTRUCTION $373,549

TOTAL COST OF MAINTENANCE AND REHABILITATION $22,356

RESIDUAL VALUE -$2,343

PRESENT WORTH $393,561

EQUIVALENT UNIFORM ANNUAL COST $19,884

Top 10 Construction Item Costs

$6,000

$6,000

$22,500

$22,500

$32,175

$41,374

$300,000

$0 $50,000 $100,000 $150,000 $200,000 $250,000 $300,000 $350,000

Year 28, Replace Cracked Pavers

Year 8, Replace Cracked Pavers

Year 35, Replace Worn/Rutted Pavers

(Wheelpath)

Year 20, Replace Worn/Rutted Pavers

(Wheelpath)

Year 0, Granular Base

Year 0, Granular Subbase

Year 0, Bedding Sand and PaverInstallation

Actual Cost ($)


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PRICEST DEV COST

PRESENT

WORTH


0 50 918.75 Tonne $95.00 $8.00 $87,281 $87,281

0 50 825 Tonne $85.00 $7.00 $70,125 $70,125

0 150 2475 Tonne $13.00 $2.00 $32,175 $32,175

0 450 7425 Tonne $8.50 $1.00 $63,113 $63,113



PRICEST DEV COST

PRESENT

WORTH

4 500 500 m $2.00 $0.50 $1,000 $855

8 5 375 Sq. m $7.00 $1.00 $2,625 $1,918

15 50 918.75 Tonne $86.00 $8.60 $79,013 $43,873

19 1000 1,000 m $2.00 $0.50 $2,000 $949

22 10 750 Sq. m $7.00 $1.00 $5,250 $2,215

25 90 1653.75 Tonne $86.00 $8.60 $142,223 $53,350

27 1000 1000 m $2.00 $0.50 $2,000 $694

30 10 750 Sq. m $7.00 $1.00 $5,250 $1,619

37 50 918.75 Tonne $86.00 $8.60 $79,013 $18,512

Asphalt Concrete Surface

Asphalt Concrete Base

Mill and Overlay Asphalt Pavement


Patching (%)


CONSTRUCTION ITEM


ASPHALT CONCRETE PAVEMENT DESIGN (FLEXIBLE PAVEMENT)

Denver Examples, Denver, Colorado

MAINTENACE ACTIVITY

Rout and Seal Cracks


Patching (%)


Granular Base

Granular Subbase

Patching (%)


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Total Pavement Area: 7,500 Sq. m 2500 Long. Concrete Joints (M or Ft) 1667 Trans. Concrete Joints (M or Ft)


PRICEST DEV COST

PRESENT

WORTH


0 7500 7500 Sq. m $60.00 $8.00 $450,000 $450,000

0 150 2475 Tonne $13.00 $2.00 $32,175 $32,175



PRICEST DEV COST

PRESENT

WORTH

5 1625 1625 m $2.00 $0.50 $3,250 $2,671

15 150 150 Sq. m $160.00 $16.00 $24,000 $13,326

18 4875 4875 m $2.00 $0.50 $9,750 $4,813

25 375 375 Sq. m $160.00 $16.00 $60,000 $22,507

30 1625 1625 m $2.00 $0.50 $3,250 $1,002

40 150 150 Sq. m $160.00 $16.00 $24,000 $4,999

43 4875 4875 m $2.00 $0.50 $9,750 $1,805



PORTLAND CEMENT CONCRETE PAVEMENT DESIGN (RIGID PAVEMENT)

CONSTRUCTION ITEM

Doweled Jointed Concrete Pavement

Granular Base

MAINTENACE ACTIVITY

Reseal Joints

Concrete Pavement Restoration

Reseal Joints


Reseal Joints


Reseal Joints


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Total Pavement Area: 7,500 Sq. m 2500 Long. Concrete Joints (M or Ft) 1667 Trans. Concrete Joints (M or Ft)


PRICEST DEV COST

PRESENT

WORTH



PORTLAND CEMENT CONCRETE PAVEMENT DESIGN (RIGID PAVEMENT)

CONSTRUCTION ITEM

TOTAL COST OF NEW CONSTRUCTION $482,175

TOTAL COST OF MAINTENANCE AND REHABILITATION $51,124

RESIDUAL VALUE -$7,030

PRESENT WORTH $526,269

EQUIVALENT UNIFORM ANNUAL COST $26,589

Top 10 Construction Item Costs

$3,250

$3,250

$9,750

$9,750

$24,000

$24,000

$32,175

$60,000

$450,000

$0 $50,000 $100,000 $150,000 $200,000 $250,000 $300,000 $350,000 $400,000 $450,000 $500,000

Year 30, Reseal Joints




Year 40, Concrete Pavement Restoration


Year 0, Granular Base


Year 0, Doweled Jointed Concrete Pavement

Actual Cost ($)


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Analysis Period: 40 YearsDiscount Rate: 4 %


TOTAL COST OF NEW CONSTRUCTION: $373,549

TOTAL COST OF MAINTENANCE ACTIVITIES AND REHABILITATION: $22,356

RESIDUAL VALUE: -$2,343

PRESENT WORTH: $393,561

EQUIVALENT UNIFORM ANNUAL COST: $19,884

FLEXIBLE PAVEMENT






RIGID PAVEMENT






Urban Pavement Design



ECONOMIC ANALYSIS REPORT



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Analysis Period: 40 Years

Discount Rate: 4 %Note: This Analysis Assumes a St. Dev. of +/- 2 for Calculation of Lower & Higher Side Present Worth Values

Year Construction Item Cost Lower Side PW Higher Side

FLEXIBLE PAVEMENT ANALYSIS

INITIAL CONSTRUCTION IN YEAR 0

0 Asphalt Concrete Surface $87,281 $72,581 $87,281 $101,9810 Asphalt Concrete Base $70,125 $58,575 $70,125 $81,675

0 Granular Base $32,175 $22,275 $32,175 $42,0750 Granular Subbase $63,113 $48,263 $63,113 $77,963

MAINTENANCE AND REHABILITATION ACTIVITIES4 Rout and Seal Cracks $1,000 $427 $855 $1,282

8 Patching (%) $2,625 $1,370 $1,918 $2,46615 Mill and Overlay Asphalt Pavement $79,013 $35,098 $43,873 $52,64719 Rout and Seal Cracks $2,000 $475 $949 $1,424

22 Patching (%) $5,250 $1,582 $2,215 $2,84825 Mill and Overlay Asphalt Pavement $142,223 $42,680 $53,350 $64,020

27 Rout and Seal Cracks $2,000 $347 $694 $1,04030 Patching (%) $5,250 $1,156 $1,619 $2,08137 Mill and Overlay Asphalt Pavement $79,013 $14,810 $18,512 $22,215

SUMMARY OF LIFE CYCLE DATA FOR FLEXIBLE PAVEMENT DESIGN

TOTAL COST OF NEW CONSTRUCTION $201,694 $252,694 $303,694

TOTAL COST OF MAINTENANCE AND REHABILITATION $97,946 $123,985 $150,024

RESIDUAL VALUE -$11,520 -$11,520 -$11,520

PRESENT WORTH $288,119 $365,158 $442,198

RIGID PAVEMENT ANALYSIS


0 Doweled Jointed Concrete Pavement $450,000 $330,000 $450,000 $570,0000 Granular Base $32,175 $22,275 $32,175 $42,075



DETAILED ECONOMIC ANALYSIS REPORT



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MAINTENANCE AND REHABILITATION ACTIVITIES5 Reseal Joints $3,250 $1,336 $2,671 $4,00715 Concrete Pavement Restoration $24,000 $10,661 $13,326 $15,992

18 Reseal Joints $9,750 $2,406 $4,813 $7,21925 Concrete Pavement Restoration $60,000 $18,006 $22,507 $27,008

30 Reseal Joints $3,250 $501 $1,002 $1,50340 Concrete Pavement Restoration $24,000 $3,999 $4,999 $5,99943 Reseal Joints $9,750 $903 $1,805 $2,708




RESIDUAL VALUE -$7,030 -$7,030 -$7,030

PRESENT WORTH $383,057 $526,269 $669,481

INTERLOCKING CONCRETE PAVEMENT (ICP) ANALYSIS


0 Bedding Sand and Paver Installation $300,000 $240,000 $300,000 $360,0000 Granular Base $32,175 $22,275 $32,175 $42,075

0 Granular Subbase $41,374 $31,639 $41,374 $51,109


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8 Replace Cracked Pavers $6,000 $3,507 $4,384 $5,26120 Replace Worn/Rutted Pavers (Wheelpath) $22,500 $8,215 $10,269 $12,32228 Replace Cracked Pavers $6,000 $1,601 $2,001 $2,401

35 Replace Worn/Rutted Pavers (Wheelpath) $22,500 $4,561 $5,702 $6,842




RESIDUAL VALUE -$1,875 -$2,343 -$2,812

PRESENT WORTH $309,924 $393,561 $477,199

Lcc a Manual

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