配置MRD的CFRP筋混凝土柱抗震性能试验

Experiment on Seismic Performance of CFRP Reinforced Concrete Column with MRD

为探讨磁流变阻尼器(MRD)对碳纤维增强复合材料(CFRP)筋混凝土柱抗震性能的影响,完成了1个普通钢筋混凝土柱和2个外置MRD的CFRP筋混凝土柱的水平低周反复荷载试验,其中MRD的电流分别为150 mA和80 mA,研究了不同电流的MRD对CFRP筋混凝土柱的破坏形态、滞回曲线、骨架曲线、刚度退化、耗能能力、残余变形等的影响以及其与普通钢筋混凝土柱的性能区别。结果表明:与钢筋混凝土柱相比,设置MRD的CFRP筋混凝土柱裂缝较为分散且发展高度较高,极限变形增大,滞回曲线更加饱满,承载力更高,耗能能力明显提升,能量耗散系数可提高104.9%,而且在合理的使用方式下残余位移大幅度减小,最多可减小76.66%,拥有较好的自复位能力;同时MRD的电流大小对CFRP筋混凝土柱抗震性能影响较大;相较于配置80 mA的MRD混凝土柱,配置150 mA的MRD混凝土柱的承载能力和耗能能力更高,能量耗散系数可以提高28.61%,且在加载过程刚度始终较大;不同电流下的MRD混凝土柱破坏模式相同,且在该使用方式下的MRD对残余变形的影响也较小。

In order to study the effect of magnetorheological damper(MRD)on seismic performance of concrete columns reinforced with carbon fiber reinforced plastics(CFRP),a low-cycle and reverse horizontal loading test was completed for one ordinary reinforced concrete column and two CFRP reinforced concrete columns with MRD,the currents of MRD were 150 mA and 80 mA,respectively.The influence of MRD with different currents for the CFRP reinforced concrete columns on the failure modes,hysteretic curves,skeleton curves,stiffness degradation,energy dissipation capacity,residual deformation and the performance differences between reinforced concrete column and CFRP reinforced concrete column with MRD were studied.The results show that compared with reinforced concrete column,CFRP reinforced concrete columns with MRD have relatively dispersed cracks and a higher development height,the ultimate deformation increases,the hysteretic curve is fuller,the bearing capacity is higher and the energy dissipation capacity is significantly improved,the energy dissipation coefficient is increased by 104.9%,moreover the residual displacement is greatly reduced in the reasonable way,up to 76.66%reduction,satisfactory self-centering capacity is shown.Simultaneously,the current of MRD has a great influence on the performance of CFRP reinforced concrete columns.Compared with the concrete column equipped with the MRD of 80 mA,the 150 mA MRD concrete column has higher bearing capacity and energy dissipation capacity,the energy dissipation coefficient is increased by 28.61%and its stiffness is always greater during loading,the initial stiffness is greater.The failure mode of concrete columns with MRD under different currents is the same,and the influence of MRD on the residual deformation is less in this way.