预应力钢绞线加固震损混凝土圆柱抗震性能试验与理论研究

为研究预应力钢绞线加固对震损混凝土圆柱的抗震特性,共设计了10个试件,其中4个为未加固试件,另外6个为不同损伤程度的加固试件,采用拟静力试验,分别研究预应力度、损伤指数和钢绞线间距对试件抗震性能影响。结果表明:所有加固试件承载力基本满足应急承载力恢复要求,加固试件位移延性系数较未加固试件有了较大提高;钢绞线预应力度对加固效果影响显著,随着预应力度的增加,试件的滞回曲线更加饱满,峰值荷载明显提高,位移延性系数显著改善;并建立了预应力钢绞线加固震损混凝土圆柱的抗剪承载力计算公式,公式计算结果和试验结果较为吻合且留有一定的安全储备,可为实际工程损伤加固提供参考。

Experimental and theoretical research on seismic behavior of the prestressed steel strand reinforcement on the seismically damaged concrete cylinder

In order to test the seismic performance of the prestressed steel strand reinforcement on the seismically damaged concrete cylinder,a total of ten specimens were designed,consisting of four unreinforced specimens and six reinforced specimens with different degrees of damage.The effects of prestress degree,damage index and steel strand spacing on the seismic performance of the specimen were tested by pseudo-static test.The results show that the bearing capacity of all the reinforced specimens basically meets the recovery requirements of emergency bearing capacity,and the displacement ductility coefficient of reinforced specimens is greatly improved compared with the unreinforced specimens.In addition,the prestress degree of steel strands has a significant effect on the reinforcement effect.With the increase of prestress degree,the hysteresis curve of specimens is fuller,the peak load is significantly improved,and the displacement ductility coefficient is obviously improved.A formula for calculating the shear capacity of the prestressed steel strand reinforcement on the seismically damaged concrete cylinder is established.The calculation results tallies with the test results.It also has a certain safety reserve,which can provide a reference for the actual engineering damage reinforcement.