1.3.3.7—Availability of repair materials and methods,
cost effectiveness, and the technical feasibility of using them
should be considered. Manufacturers or suppliers can provide
assistance in the selection of repair materials and application
techniques. When selecting the appropriate repair material,
one should keep in mind that the technical data presented in
manufacturer’s literature may not be sufficient because the
tests performed may not be representative of the use of the
material in a particular application.
1.3.3.8—The engineer should try to determine the extent
of reinforcement deterioration and if there is a need for
temporary shoring. If the steel reinforcement becomes
partially or totally ineffective, has corroded, or has been cut
during concrete removal at critical locations, such as in
columns, at the ends of beams, or on the tension sides of
beams, the redistribution of loading stress in the element’s
cross section takes place. In most cases, unless the dead and
live loads are removed before repair work, the repaired portion
of the element is not effective in supporting existing loads. In
short, the repair is nonstructural. In those cases where
restoration of load-carrying capacity is a primary concern,
existing loads need to be removed and members need to be
jacked-up and shored to support dead loads.
1.3.3.9—The capabilities of potential contractors to use
specialized repair materials and techniques and to successfully
execute repair procedures should be evaluated, considering
both initial and long-term costs. Contractors should be capable
of demonstrating their expertise in this type of construction.
1.3.4 Preparation of drawings and specifications—The
next step in the repair process is the preparation of project
drawings, specifications, or both. Because the full extent of
concrete damage may not be completely known until
concrete removal begins, drawings and specifications for
repair projects should be prepared with as much flexibility as
possible regarding work items such as concrete removal,
surface preparation, reinforcement replacement, and quantities
of repair materials. A comprehensive condition survey
performed as close as possible to the time that the repair work
is executed may help to minimize variations in estimated
quantities of actual repair work.
When deterioration is particularly severe or where extensive
concrete removal is anticipated, provisions for temporary
structural support should be included in the project documents.
Protection of the repair site and adjacent areas may present
unique problems during the execution of a repair project.
Special attention should be given to shoring and bracing of
structural components under repair and adjacent framing.
Shoring may be particularly necessary for slab and beam
repairs and, in some cases, for column repairs. Redistribution
of loading during repair is important for continuous slabs,
beams, or girder systems, and is especially critical for
unbonded prestressed structures. Contingency provisions
should be included in the drawings and specifications for
addressing potential increases in the scope of work.
Effective repair specifications should be clear and concise.
Repair specifications should include the quantities of the
repair units, the scope of the work, the materials requirements,
surface preparation, the application considerations,
and the performance testing standards with reference to
specific requirements such as tensile strength, surface
profiling, compressive strength, bond strength, and related
support documents. Details of the concrete repair should be
provided, parameters for concrete removal should be defined
and, if possible, boundaries of concrete removal and replacement
should be identified along with any special features of
repair system installation that are necessary. Special attention
to the details of reinforcement repair or replacement
areas and the preparation of existing concrete before surface
protection system application is required. The contract documents
should provide sufficient information to the prospective
contractors on concrete condition that were found during
the investigation stage.
1.3.5 Bid and negotiation process
1.3.5.1 Selection of a contractor—One of the most
important aspects of a repair project is the selection of a
qualified contractor or the preparation of a list of qualified
bidders. No repair contractors are proficient in all phases of
all types of repair work. If possible, select contractors who
have shown evidence of expertise and successful completion
in each type of repair work included in the project.
1.3.5.2 Prebid conference—Before bids are submitted,
the engineer, owner, and potential contractors should have a
prebid conference to answer any questions regarding the
project documents as well as defining the intent of the
document, expectations of the owner, or both. If possible,
this meeting should include a visit to the repair site. This
meeting can go a long way toward eliminating disputes and
claims during the construction process.
1.3.5.3 Preconstruction conference—Before starting a
project, it is important to have the owner and engineer meet
the project manager and superintendent. At this meeting, the
contractor should be prepared to present the schedule to
determine its acceptability to the owner and determine if
there are going to be any conflicts with daily operations that
should be resolved. Defining the frequency and types of
reports helps all parties concerned with ensuring the means
and methods that are used to communicate progress,
discovered items, and construction problems.
1.3.6 Execution of the work—Repair work is executed in
accordance with project drawings and specifications. The
repair process generally consists of deteriorated or damaged
concrete removal, surface preparation, the installation of
repair materials, and the implementation of specified repair
techniques. Protection may also be incorporated into the
repair process.
1.3.3.7—Availability of repair materials and methods,cost effectiveness, and the technical feasibility of using themshould be considered. Manufacturers or suppliers can provideassistance in the selection of repair materials and applicationtechniques. When selecting the appropriate repair material,one should keep in mind that the technical data presented inmanufacturer’s literature may not be sufficient because thetests performed may not be representative of the use of thematerial in a particular application.1.3.3.8—The engineer should try to determine the extentof reinforcement deterioration and if there is a need fortemporary shoring. If the steel reinforcement becomespartially or totally ineffective, has corroded, or has been cutduring concrete removal at critical locations, such as incolumns, at the ends of beams, or on the tension sides ofbeams, the redistribution of loading stress in the element’scross section takes place. In most cases, unless the dead andlive loads are removed before repair work, the repaired portionof the element is not effective in supporting existing loads. Inshort, the repair is nonstructural. In those cases whererestoration of load-carrying capacity is a primary concern,existing loads need to be removed and members need to bejacked-up and shored to support dead loads.1.3.3.9—The capabilities of potential contractors to usespecialized repair materials and techniques and to successfullyexecute repair procedures should be evaluated, consideringboth initial and long-term costs. Contractors should be capableof demonstrating their expertise in this type of construction.1.3.4 Preparation of drawings and specifications—Thenext step in the repair process is the preparation of projectdrawings, specifications, or both. Because the full extent ofconcrete damage may not be completely known untilconcrete removal begins, drawings and specifications forrepair projects should be prepared with as much flexibility aspossible regarding work items such as concrete removal,surface preparation, reinforcement replacement, and quantitiesof repair materials. A comprehensive condition surveyperformed as close as possible to the time that the repair workis executed may help to minimize variations in estimatedquantities of actual repair work.When deterioration is particularly severe or where extensiveconcrete removal is anticipated, provisions for temporarystructural support should be included in the project documents.Protection of the repair site and adjacent areas may presentunique problems during the execution of a repair project.Special attention should be given to shoring and bracing ofstructural components under repair and adjacent framing.Shoring may be particularly necessary for slab and beamrepairs and, in some cases, for column repairs. Redistributionof loading during repair is important for continuous slabs,beams, or girder systems, and is especially critical forunbonded prestressed structures. Contingency provisionsshould be included in the drawings and specifications foraddressing potential increases in the scope of work.Effective repair specifications should be clear and concise.Repair specifications should include the quantities of therepair units, the scope of the work, the materials requirements,surface preparation, the application considerations,and the performance testing standards with reference tospecific requirements such as tensile strength, surfaceprofiling, compressive strength, bond strength, and relatedsupport documents. Details of the concrete repair should beprovided, parameters for concrete removal should be definedand, if possible, boundaries of concrete removal and replacementshould be identified along with any special features ofrepair system installation that are necessary. Special attentionto the details of reinforcement repair or replacementareas and the preparation of existing concrete before surfaceprotection system application is required. The contract documentsshould provide sufficient information to the prospectivecontractors on concrete condition that were found duringthe investigation stage.1.3.5 Bid and negotiation process1.3.5.1 Selection of a contractor—One of the mostimportant aspects of a repair project is the selection of aqualified contractor or the preparation of a list of qualifiedbidders. No repair contractors are proficient in all phases ofall types of repair work. If possible, select contractors whohave shown evidence of expertise and successful completionin each type of repair work included in the project.1.3.5.2 Prebid conference—Before bids are submitted,the engineer, owner, and potential contractors should have aprebid conference to answer any questions regarding theproject documents as well as defining the intent of thedocument, expectations of the owner, or both. If possible,this meeting should include a visit to the repair site. Thismeeting can go a long way toward eliminating disputes andclaims during the construction process.1.3.5.3 Preconstruction conference—Before starting aproject, it is important to have the owner and engineer meetthe project manager and superintendent. At this meeting, thecontractor should be prepared to present the schedule todetermine its acceptability to the owner and determine ifthere are going to be any conflicts with daily operations thatshould be resolved. Defining the frequency and types ofreports helps all parties concerned with ensuring the meansand methods that are used to communicate progress,discovered items, and construction problems.1.3.6 Execution of the work—Repair work is executed inaccordance with project drawings and specifications. Therepair process generally consists of deteriorated or damagedconcrete removal, surface preparation, the installation ofrepair materials, and the implementation of specified repairtechniques. Protection may also be incorporated into therepair process.
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