型钢再生混凝土高轴压比柱抗震性能试验

摘要

To study the seismic behaviors of full-scale steel reinforced recycled concrete columns under high axial compression ratio,the columns with three types of recycled coarse aggregate replacement rate under different axial compression ratios were designed,and four specimens were experimented on the 40 000 kN multi-function testing machine under low cyclic reversed loading.The influences of different design variables on horizontal load bearing capacity, hysteretic behavior, skeleton curves, energy dissipation, deformation and stiffness degradation of specimens were obtained after observing the mechanical processes and failure patterns. The results show that the ultimate failure pattern of the four specimens is the bending-shear failure and the hysteresis loop of each column is relatively plump,indicating that the columns show good energy dissipation behavior.The increase of the recycled coarse aggregate replacement rate decreases the deformability,but it has little influence on the bearing capacity and stiffness degradation of the specimens.With the increase of axial compression ratio, the load-bearing capacity, stiffness and energy dissipation behavior of specimens raise, but the stiffness and bearing capacity degradation intensifies and the ductility declines acutely. The steel reinforced recycled concrete columns with high axial compression ratio can still maintain good seismic performance, and this study provides the basis for subsequent theoretical research and practical engineering application.%为研究3种不同再生粗骨料取代率的足尺型钢再生混凝土柱试件在高轴压比及较低轴压比下的抗震性能差异,本文通过40000 kN多功能试验机对4个柱试件进行了低周反复荷载试验.观察分析各试件的受力性能及破坏特征,得到不同设计变量对试件的水平承载力、滞回性能、骨架曲线、耗能、变形及刚度等的影响规律.结果表明:4个柱试件的最终破坏形态均为弯剪破坏;各试件滞回曲线较饱满,试件耗能性能较好;再生粗骨料取代率增大,会使试件的变形能力有所降低,但对试件水平承载力及刚度退化影响不大;轴压比增大,试件的水平承载力、刚度及耗能性能提高,但承载力下降加快,刚度退化加剧,延性降低.总体来看,型钢再生混凝土柱在高轴压比下仍然能保持较好的抗震性能,可为后续的理论研究及实际工程应用提供依据.