Materials and Design Considerations in FRP Rehabilitation of Concrete Structures

Fiber reinforced polymer matrix composites are increasingly being considered for use in repair, strengthening and retrofit of concrete structures. The technology is now at a point where its future acceptance will depend primarily on the availability of validated design guidelines based on accepted performance criteria, and on the economic competitiveness of these technologies as compared to conventional methods of rehabilitation. The myriad possibilities of reinforcement and resin combinations, and processing paths possible with PMCs make it important that the guidelines include provisions for materials and process selection, failure mechanisms, and design detailing. The efficiency of the rehabilitation measure and its efficacy depend not just on the application of the composite to the structure, but rather on the development of appropriate design detailing measures based on mechanics of bond transfer, failure modes/fracture mechanisms, and systems structural response. This paper discusses a number of these aspects with specific emphases on materials and processes, integrating aspects from the areas of mechanics, materials science of composites and polymers, and civil engineering design and detailing practice. words: Composites, rehabilitation, retrofit, concrete 1805 1 addition to deterioration and degradation caused through aging, weathering of materials, and accidental damage to structures, our traffic needs have increased dramatically over the past two decades with transportation of goods and services being conducted on a global, rather than local basis, resulting in a growing need for the widening of our highway systems to accommodate more lanes, and for the renewal of existing structures to carry heavier loads at higher speeds. Enhanced understanding of structural response has led to the establishment of new design codes and the need to rehabilitate existing structures to ensure safety.