Calculating method of projection length of diagonal cracks of RC beams reinforced with CFRP strips

doi:10.19936/j.cnki.2096-8000.20230428.008

Abstract

Abstract: The shear tests of 18 RC beams reinforced with CFRP strips are carried out, and the impact of shear span ratio, spacing of CFRP strips and pre-cracked degree on the projection length of diagonal cracks of CFRP reinforced RC beams is investigated. The experimental results show that with the decrease of the spacing of CFRP strips, the development rate of the diagonal cracks decreases gradually, while the number of diagonal cracks increases. As the pre-cracked degree increases, the development rate of diagonal cracks increases, the number and projection length of diagonal cracks increase. Shear span ratio is the main parameters affecting the development of diagonal cracks and the length of projection. As shear span ratio increases, the projection length of diagonal cracks increases gradually. On the basis of experimental research, considering the influence of shear span ratio, spacing of CFRP strips and pre-cracked degree, a formula for calculating horizontal projection length of diagonal cracks of the CFRP reinforced RC beams is put forward.

Key words: CFRP, reinforcement, concrete beam, shear performance, diagonal crack, shear span ratio, pre-cracked degree

CLC Number:

TB332

GUO Weidong, YU Feng, TAN Siyong, FANG Yuan, QIN Yin, WANG Zongsen, GUO Shengquan. Calculating method of projection length of diagonal cracks of RC beams reinforced with CFRP strips[J]. COMPOSITES SCIENCE AND ENGINEERING, 2023, 0(4): 51-55.

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