01 - Condition Assessment

CIVE 527 – Renovation & Preservation of the Infrastructure

As engineers we are quite capable of building impressive structures to survive in very hostile environments for extended periods of time (?)


However, much of our infrastructure is suffering from premature deterioration, failing to provide the (repair-free) service we expected.


In 1991, a report from the Transportation Research BoardIn 1991, a report from the Transportation Research Board estimated that the annual cost of bridge deck repairs due to the use of deicing salts may be as high as $200M, with substructures and other components requiring an additional $100M per year.

Repairs on multistorey car parks were estimated to require a further $50M to $150M per year.

B fi ld 1997Broomfield, 1997


In 1991, it was estimated that nearly 50% of constructionexpenditures were directed towards repair and refurbishment of existing structures.

Mailvaganam


Report Card for America’s Infrastructure

BRIDGES: C

Between 2000 and 2003, the percentage of the nation’s 590,750 bridges rated structurally deficient or functionally obsolete decreased slightly from 28.5% to 27.1%.

However, it will cost $9.4 billion a year for 20 years to eliminate all bridge deficiencies. Long-term underinvestment is compounded by the lack of a Federal transportation program.

ASCE, 2005


4-YEAR CHANGE (2005-2009)

AVIATION: D (Down from D+)

ENERGY: D+ (Up from D)

ROADS: D- (Down from D)

TRANSIT: D (Down from D+)

Estimated 5-Year Investment Need:

$2.2 Trillion (Up from $1.6 Trillion)


Condition Assessment:

“An examination of a structure for the purpose of identifying and defining areas of distress.”

ACI 201.1R-92


Inspection:

R f t th t l i ti ti f t t OftRefers to the actual investigation of a structure. Often includes field and/or laboratory testing of materials or components.

Condition Assessment:

Refers to a more global approach to determining theRefers to a more global approach to determining the current condition of a structure. Uses design, construction and inspection data to formulate assessment.


Types of Inspection:

1. Inventory Inspection2. Routine Inspection3. In-Depth Inspection4. Interim Inspection5. Damage Inspection


Inventory Inspection (Global)

First inspection when a structure becomes part of the structure inventory.

May also apply to a change in configuration of a structure.

Sets baseline for future inspections.


Routine Inspection (Global)

Regularly scheduled inspection to monitor performance of a structure.

Determine physical and functional condition of structure.

Identify any potential or developing problems.


In-Depth Inspection (Global)

Close-up hands-on inspection to detect deficiencies not readily visible.

More detailed than Routine Inspection.

Often a scheduled supplement to Routine Inspection but at longer intervals.


Interim Inspection (Local)

Scheduled inspection to monitor a particular known or suspected deficiency.

Frequency will depend on severity of deficiency and rate of deterioration.


Damage Inspection (Local)

Unscheduled inspection to assess damage resulting from a specific cause.

Must be sufficient to determine need for restrictions/closure/repair.p

Detail of inspection depends on extent of damage.


Assessment Planning

Preliminary Assessment Condition AssessmentGeneral Approach

Preliminary Evaluation

Cost-Impact Study

RecommendationsYES

General Approach

SufficientInformation

???

Cost-Impact Study

Report of Assessment

Detailed Assessment

Detailed Evaluation

NO


Assessment Planning

Determine the general approach that will be followed during the condition assessment.

- Why is the assessment being performed?

- What needs to be investigated? What doesn’t?

- Who will be involved? What permissions are needed?

What portions/b ildings ill be assessed?- What portions/buildings will be assessed?

Remember the Golden Rule …..

CONDITION ASSESSMENTS ARE EXPENSIVE !!!


Preliminary Assessment

Provides the initial data for estimating structural gadequacy and establishes the need/priorities for a more detailed investigation.

Basic components:

1. Review of available documents

2 Sit i ti2. Site inspection

3. Preliminary analysis

4. Preliminary findings & recommendations


1. Review of Available Documents

Used to expedite the site inspection process.p p p

Should include whatever relevant documentation still exists from the design/construction phase.

Some documents to consider - design plans and d i d i it i l l ti ifi tidrawings, design criteria, calculations, specifications, soil investigations, as-built drawings, maintenance records.

If not available, required info must obtained at the site.


2. Site Inspection

Allows confirmation of existing design information and g gassessment of the structural condition of the building.

Things to look for - structural modification, deterioration of materials, discrepancies in documentation, weakness in structural members or connections, settlement or foundation problems, unusual structuralsettlement or foundation problems, unusual structural features, changes in use of structure, obvious damage.

Typically visual in nature with little or no testing.


3. Preliminary Analysis

Provides the basis for:

- Estimating structural capacity

- Assessing property damage

- Identifying structural deficiencies w.r.t. codes

- Identifying deterioration problems

- Environmental effects on structure


3. Preliminary Analysis

Key aspects to determine:y p

- Loading and performance criteria (codes)

- Identity of primary structural components

- Material properties

- Member and connection analysis

- Nonstructural components

- Exposure conditions


4. Preliminary Findings & Recommendations

Report on the results of a preliminary investigation. p p y gShould include:

1. Description of building.

2. Description of loading and performance criteria considered.

3. Description of preliminary evaluation process.

4 Di i f li i fi di4. Discussion of preliminary findings.

5. Recommendations concerning the need for particular actions (i.e. cease investigation, detailed assessment).


Cost-Impact Study

An estimate of the cost for rehabilitating the structure.g

Should include indirect costs such as disruption of usage, temporarily vacating structure and detailed assessment if necessary.

Will f th b i f d i i di thWill form the basis for a decision regarding the economic feasibility of the rehabilitation project.

If it indicates that rehabilitation is economically feasible, a more detailed assessment may be required.


Detailed Assessment

Purpose:p

1. Determine if the building satisfies required performance criteria or requires rehabilitation.

2. Identify deficiencies and recommend alternatives for rehabilitation.

Similar to preliminary assessment but in greater detail and with more accuracy in order to increase reliability of recommendations. May require extensive investigative testing.


Cost-Impact Study

Similar to previous cost-impact study.p p y

A more refined estimate of the cost for rehabilitating the structure.

Final decision of action is often based upon cost.

May require multiple estimates for varying recommendations.


Final Recommendations

Summary of the detailed assessment (if performed).y ( p )

Recommendations as to the appropriate course of action, which could include:

1. Acceptance of structure as is.

2. Rehabilitating structure to correct deficiencies.

3. Changing the use of the building.

4. Phasing the building out of service.


Why do Condition Assessments?

Safety Repairs Modifications Litigation

TotalCost

y p g

Economics

Time


01 - Condition Assessment

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