“cost effective vartm technology for repair and ... resulting from repair of a deck/beam could...

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7. “CostEffective VARTM Technology for Repair and StrengtheningPhase IIII,” Alabama DOT/FHWA 930607 Highway Administration (FHWA) estimates that the US currently faces a $167 billion cost to repair deficient bridges and roads; and over 40 percent of the nation’s bridges are in need of repair or replacement. The National Research Council’s Transportation Research Board recently estimated that the improvement of infrastructure by as little as one percentage point over a 20‐year period would result in saving of $10‐30 billion (Six, 1992). In many cases, retrofit and rehabilitation by conventional means is very costly (due to both specialized equipment needs and closure of the structure during repair), if not impossible (e.g., the additional dead load resulting from repair of a deck/beam could very well further damage the structure and cause its final failure). There is an increasing need for the application of new materials and technique capable of rapidly retrofitting and/or rehabilitating infrastructure components (bridge girders, decks, piers, piling, support structure, guardrail and roadside barriers etc.). The overall objectives of this work (with Prof. Vaidya of MSE) are to complete critical follow‐on tasks to pioneer the new and promising Vacuum Assisted Resin Transfusion Method (VARTM) technology to address the issue of low cost repair and strengthening of bridge structures and develop design guidelines and specifications of VARTM method for flexural and shear strengthening of the bridge girder. A key aspect of this technology will be repair implementation at low cost requiring specialized equipment and closure of structure during repair; and selection and optimization of the FRP composite materials, which offer a considerable weight advantage over traditional construction materials. Another basic consideration is given to cost‐ effectiveness due to innovative key technologies that can within short timelines be readily implemented in the field. The proposed work will include. Investigating influential parameters including durability factors affecting VARTM strengthened FRP/Concrete interface behavior, Development of viable details, and design and repair guidelines necessary for optimum and safe uses of proposed stiffening/strengthening technique A procedure for documenting the behavior of the bridge girders in their cracked state, and a bridge repair technique for these cracked girder ends Develop detailed specifications and quality control procedure so that the repairs can be performed by a contractor Perform a series of follow‐up tests designed to document the girder's post‐repair behavior once the contractor is completed his work. Through various field applications across Alabama, this novel VARTM technology will be successfully transformed into practice. For more information concerning this research project, click on an investigator(s) name below: Nasim Uddin, Professor.

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Page 1: “Cost Effective VARTM Technology for Repair and ... resulting from repair of a deck/beam could very well further damage the structure and cause its final failure). There is an increasing

7.  “Cost­Effective VARTM Technology for Repair and Strengthening­Phase I­III,” Alabama DOT/FHWA 930­607 Highway Administration (FHWA) estimates that the US currently faces a $167 billion cost to repair deficient bridges and roads; and over 40 percent of the nation’s bridges are in need of repair or replacement. The National Research Council’s Transportation Research Board recently estimated that the improvement of infrastructure by as little as one percentage point over a 20‐year period would result in saving of $10‐30 billion (Six, 1992). In many cases, retrofit and rehabilitation by conventional means is very costly (due to both specialized equipment needs and closure of the structure during repair), if not impossible (e.g., the additional dead load resulting from repair of a deck/beam could very well further damage the structure and cause its final failure).  There is an increasing need for the application of new materials and technique capable of rapidly retrofitting and/or rehabilitating infrastructure components (bridge girders, decks, piers, piling, support structure, guardrail and roadside barriers etc.). The overall objectives of this work (with Prof. Vaidya of MSE) are to complete critical follow‐on tasks to pioneer the new and promising Vacuum Assisted Resin Transfusion Method (VARTM) technology to address the issue of low cost repair and strengthening of bridge structures and develop design guidelines and specifications of VARTM method for flexural and shear strengthening of the bridge girder. A key aspect of this technology will be repair implementation at low cost requiring specialized equipment and closure of structure during repair; and selection and optimization of the FRP composite materials, which offer a considerable weight advantage over traditional construction materials.  Another basic consideration is given to cost‐effectiveness due to innovative key technologies that can within short timelines be readily implemented in the field. The proposed work will include. Investigating influential parameters including durability factors affecting VARTM strengthened FRP/Concrete interface behavior,  • Development of viable details, and design and repair 

guidelines necessary for optimum and safe uses of proposed stiffening/strengthening technique  

• A procedure for documenting the behavior of the bridge girders in their cracked state, and a bridge repair technique for these cracked girder ends  

• Develop detailed specifications and quality control procedure so that the repairs can be performed by a contractor   

• Perform a series of follow‐up tests designed to document the girder's post‐repair behavior once the contractor is completed his work.   

Through various field applications across Alabama, this novel VARTM technology will be successfully transformed into practice. For more information concerning this research project, click on an investigator(s) name below: Nasim Uddin, Professor.