Analysis of RC beams strengthened with SMA/prestressed CFRP sheets
Experimental study was conducted on the flexural performance of reinforced concrete beams to verify the effectiveness of the reinforcement technology of prestressed carbon fiber reinforced polymer(CFRP)sheet by the recovery stress generated by shape memory alloy(SMA)wire heating.Bending performance test specimen with pre-stress of 100 MPa and 200 MPa were experimen-tally produced.The failure mode,load deflection curve,and strain development process of the test beam were analyzed.A stress analysis method for the entire bending process of the reinforced beam was proposed.The results show that the stress-strain loading unloading relationship curves of SMA wire under different prestrains are basically consistent during loading unloading cycles in the yield stage and strengthening stage.When the prestrain of SMA wire is 10%,the maximum recovery stress reaches 448.5 MPa.Under the same prestrain conditions,the maximum recovery stress of CFRP sheets is reduced by 37.8%to 39.5%by introducing prestress through heating recovery.The cracking moment and yield moment of the reinforced beam have significantly increased.Due to the end peeling failure of CFRP sheets,the prestressing effect does not effectively limit the development of cracks,and the stiff-ness improvement is limited.The calculation results are in good agreement with the experimental results,proving that the proposed bending whole process analysis method in this paper can be used to predict the bending mechanical properties of SMA wire reinforced beams with pre-stressed CFRP sheets due to the recovery stress caused by temperature rise.
prestressingintroduction methodstrengtheningreinforced concrete beamsentire process stress
万方数据
维普
