Thermal compatibility and bond strength of FRP reinforcement in prestressed concrete applications.

摘要

Thermal stresses and associated damage within the concrete cover of structural elements reinforced with FRP were initially studied using a linear elastic analysis. The analysis revealed susceptibility of thermal stresses to the compressive strength of concrete, transverse elastic modulus and transverse coefficient of thermal expansion (transverse CTE) of the reinforcement. A finite element analysis was also performed to include nonlinear material behavior and consideration of biaxial stress states within the concrete cover.; In view of determining whether damage arising from thermal stresses was sufficient to cause reductions in bond strength of FRP reinforcement in concrete, beams with minimum concrete cover provisions were subjected to thermal gradients expected in the Canadian climate. These beams were designed according to CSA S806 (2002) specifications and requirements for the design and construction of concrete structures with FRP. All beams were prestressed to increase potential for damage within the concrete cover. Results from the linear elastic and finite element analyses were used to determine expected damage within the concrete cover of the beams on the basis of material properties of CFRP and GFRP reinforcement used in the experimental program as well as concrete cover provided. (Abstract shortened by UMI.)