Character analysis of flexural design for concrete beams with FRP reinforcement

摘要

Owing to the shortages of brittle failure and low stiffness existing in concrete beams with FRP reinforcement, it is easy to reach a general conclusion on the beams with poor deformability and failure precursors. The analysis on the flexural behavior of concrete beams reinforced with FRP bars is performed from the point of view of engineering design. Four test beams from two published experiments are used as analytical samples and the design calculation method based on the general principle of concrete flexural members are also taken advantage of in the analysis. The results indicate that the design of concrete beams with FRP bars needs to be controlled by service limit. The stresses of FRP bars in a concrete beam are much lower at the failure state of the member, which means the use of material strength is lower. From the service limit to the rupture limit, the members can develop enough flexural deformability and provide obvious broken precursor and much higher strength reserve.