软索连接装配式工字形圆孔墙抗震性能试验研究

Experimental research on seismic behavior of assembled I-shaped perforated wall connected by soft cable

为研究纵、横向墙体采用软索连接的装配式钢筋混凝土圆孔墙结构的抗震性能,对2种不同连接方式(工字Ⅰ型、工字Ⅱ型)的足尺工字形圆孔墙试件进行了不同轴压力作用下的拟静力试验。通过试验现象发现:随着循环加载的进行,试件主翼墙交界处出现较大裂缝,试件破坏时主翼墙交界处顶部混凝土压溃;无轴压力作用时,试件屈服前的裂缝主要分布于翼墙,主墙裂缝沿着45°方向发展;有轴压力作用时,试件屈服前的裂缝主要分布于主墙,主墙裂缝沿着60°方向发展,试件破坏时主墙裂缝分布更加密集。试验结果表明:无轴压力作用时,加载后期墙体出现滑移,工字Ⅰ型试件的屈服荷载比工字Ⅱ型试件大11%,峰值荷载小9%。有轴压力作用时,试件未出现明显滑移,工字Ⅰ型试件的连接可靠性、承载力、整体变形能力较工字Ⅱ型试件的强,刚度退化慢;相比无轴压力作用时,两种连接方式试件的屈服荷载均提高110%左右,峰值荷载分别提高101%和77%,极限位移角分别提高了200%和97%,消除了因连接方式不同对开裂荷载的影响。工字Ⅰ型试件更适用于有轴压力作用的情形,工字Ⅱ型试件更适用于无轴压力作用的情形。

To study the seismic performance of assembled reinforced concrete perforated walls connected by soft cables,two kinds of full-scale Ⅰ-shaped wall specimens connected by soft cables(Ⅰ-shaped Ⅰ,Ⅰ-shaped Ⅱ) were tested under low cyclic lateral loads with different levels of axial compression.Through the tests it can be found that,with the increase of cyclic loading,large cracks appear at the junction between the main wall and the wing wall.The damage of the specimen is in the form of concrete crushing at the top of the junction between the main wall and wing wall.Without axial compression,cracks are mainly distributed in the wing wall before yielding,as well as the main wall cracks develop at an angle of 45°.With the action of axial compression,cracks are mainly distributed in the main wall before yielding,with cracks in the main wall developing more intensively at 60°.The test results indicate that:when there is no axial compression,the walls slip in the later stages of loading.The yield load of Ⅰ-shaped Ⅰspecimen is 11% larger than that of Ⅰ-shaped Ⅱ specimen,and the peak load of Ⅰ-shaped specimen Ⅰ is 9%smaller than that of Ⅰ-shaped Ⅱ specimen.When axial compression is present,the specimen does not exhibit any notable slip.Compared with the Ⅰ-shaped Ⅱ specimen,the connection of the Ⅰ-shaped Ⅰ specimen is more reliable with higher bearing capacity and higher overall deformability,and the stiffness degrades more slowly.Compared with the case that without axial compression,the yield load of the two kinds of specimens connected by soft cables both increase by about 110%,while the peak load increase by 101% and 77%,respectively.The ultimate displacement angle of the two specimens also increase by 200% and 97%,respectively,and the influence of the different connections on the cracking load is eliminated.The Ⅰ-shaped Ⅰ specimen is suitable for the case with axial compression,and the Ⅰ-shaped Ⅱ specimen is suitable for the case without axial compression.