高轴压比下钢管高强混凝土组合剪力墙抗震性能试验研究

通过在约束边缘构件位置和截面中部设置多根钢管，形成了一组不同钢管布置形式的钢管高强混凝土组合剪力墙。通过对8片剪跨比为2.08的剪力墙试件在高轴压比（0.40~0.62）下的低周往复加载试验，研究其破坏形态、承载力、变形能力、滞回性能等。试验结果表明：试件的破坏形态为压弯作用下的受弯破坏，墙体根部混凝土压溃范围为整个试件宽度和300~400mm高度，钢管与混凝土之间没有出现明显的黏结滑移；在峰值荷载前，试件的截面应变分布基本符合平截面假定；与钢筋混凝土剪力墙相比，设置钢管后在轴向压力最大增加19%的情况下，受弯承载力提高了21%~43%，试件的屈服位移角达到1/300，峰值荷载时位移角不低于1/100，极限位移角达到1/75，个别试件接近1/40，变形能力提高了约30%，试件的滞回性能明显改善，表明所设计的钢管高强混凝土剪力墙具有良好的抗震性能和抗倒塌能力。

Experimental study on seismic behavior of high-strength concretefilled steel tube composite shear walls underhigh axial compression ratio

By setting several steel tubes inside the confined boundary elements and/or the center of a high-strength shear wall, a group of high-strength concrete filled steel tube (CFST) composite shear walls with different CFST layouts have been proposed. Seven high-strength concrete-illed steel tube (CFST) composite shear wall specimens with four types of CFST layouts and one reinforced concrete (RC) shear wall specimens with different detailing methods were designed and tested under high axial compression ratio and cyclic lateral loading. The shear span depth ratio of all specimens was 2.08 and the axial compression ratio ranged from 0.40 to 0.62. The test results indicate that the specimens fail in flexural failure mode and the concrete crushed area concentrates to the bottom of each specimen with a width of the whole specimen cross section and a height of 300-400 mm. No obvious slip is observed between the steel tubes and the surrounding concrete. The measured vertical strain distribution along the wall section height basically satisfies the plane-section assumption before the peak load. Compared with the RC shear wall specimen, the flexural bearing capacity of the CFST shear wall specimens is increased by about 21%-43% while the maximum increment of its axial compression force is about 19%. The drift ratios at the yield load, the peak load and the ultimate load reach about 1/300, more than 1/100 and 1/75, respectively. Some specimens’ drift ratios at the ultimate stage reaches 1/40, and the deformation capacity increases about 30%. The hysteretic behavior of the CFST shear wall specimens is improved significantly. It can be concluded that the high-strength CFST composite shear walls designed here have an excellent seismic performance and collapse prevention capacity.