In order to investigate the flexural performance of recycled aggregate concrete(RAC)beams which were damaged by load and then reinforced with carbon fiber reinforced polymer(CFRP)sheets,9 RAC beams were designed by selecting different replacement rates of recycled aggregate.The initial damage of test beam was obtained by preloading.After unloading,CFRP sheets of different widths were pasted at the bottom of the damaged beam for reinforcement,and then bending bearing capacity tests were conducted on the test beam.Considering the influence of recycled aggregate content and pre-damage degree,a formula for calculating the flexural capacity of the damaged recycled concrete beam strengthened by CFRP sheet during delamination failure was proposed.The results show that the cracks caused by pre-damage reduces the bonding strength between CFRP sheets and RAC beams,and the reinforced beams all exhibit debonding failure.As the replacement rate of recycled aggregate increases,the width and number of cracks generated by the test beam under the same load gradually increase,and the ultimate bearing capacity decreases.As the width of CFRP sheet increases,the deflection during the failure of test beam decreases,the ultimate bearing capacity increases,and the crack distribution is fine and dense.As the degree of pre-damage increases,the crack width and number during the failure of test beam gradually increase,but the changes in ultimate bearing capacity and deflection are not significant.The calculated bending bearing capacity values are in good agreement with the experimental values.The research results can provide reference for the evaluation of the mechanical performance of damaged RAC beams strengthened with CFRP sheets.
关键词
再生混凝土梁/碳纤维布/再生骨料取代率/受弯性能
Key words
recycled aggregate concrete beam/CFRP sheet/replacement rate of recycled aggre-gate/flexural capacity
维普
万方数据