NiTiNb-SMA丝主动加固RC圆柱抗震性能试验

Experimental Study on Seismic Performance of Active Confined RC Piers with NiTiNb-SMA Wires

为研究国产镍钛铌形状记忆合金(NiTiNb-SMA)丝主动约束加固钢筋混凝土墩柱的抗震性能,完成了3个墩柱试件的拟静力试验.基于试验现象和水平力-位移曲线,对比分析了各试件的骨架曲线、承载力和延性、强度退化、累计耗能、残余位移等性能指标.结果表明:热激励NiTiNb-SMA丝能有效地为墩柱提供主动约束应力,减轻墩柱的损伤,并提高墩柱的延性和耗能能力,对比原试件,NiTiNb-SMA丝对试件主动加固后的位移延性系数和累计耗能分别提高了27.8%和10.4%;有效减缓了墩柱的强度衰减,减小了墩柱的残余位移.

To investigate the seismic performance of reinforced concrete(RC)piers retrofitted by active confinement of domestic NiTiNb-SMA wires,a pseudo-static test of three column specimens was carried out.Based on the experimental phenomena and lateral force-displacement curves,the skeleton curves,bearing capacity and ductility,strength degradation,cumulative energy dissipation and residual displacement of the specimens were analyzed.The results show that thermal excited NiTiNb-SMA wires can effectively provide active confinement stress for the pier,which reduced the damage and improved the ductility and energy dissipation capacity of piers.Compared with the control specimens,thermal excited SMA wires increased the displacement ductility coefficient and cumulative energy dissipation of the specimen by 27.8%and 10.4%,respectively.What′s more,it effectively reduced the strength degradation and improved the ability of restoring the residual displacement of piers.