Ứng xử cắt của dầm bê tông cốt GFRP

Abstract

There are limited research stuties conducted on shear strengths of FRP reinforced concrete beams in Vietnam.The stress-strain behaviors of FRP bars are very much different from the ones of traditional steel bars, which lead to the differences in shear strengths in these concrete structures. This paper consists of two parts. In the first part of the paper, the existing guidelines for shear strengths of FRP reinforced concrete beams are reviewed. The experimental program consisting of two GFRP reinforced concrete beams with an aspect ratio of 2.3 and 2.8 is presented in the second part of the paper. The shear strengths from the tested beams are used to verify the existing guidelines for shear strengths of FRP reinforced concrete beams. The experimental results indicate that the aspect ratio affects the shear strength of FRP reinforced concrete beams. The ACI 440.1R and CSA S806 codes give a fair estimation the shear strengths of tested beams. The ratios of analytical shear strengths over the experimental ones for ACI 440.1R and CSA S806 codes are 0.907 and 0.893, respectively.