钢筋套筒灌浆搭接连接的预制剪力墙抗震试验

Experimental Study on Seismic Behavior of Precast Shear Walls with Reinforcement Spliced by Grouted Sleeve Lapping Connector

摘要:

为改善钢筋灌浆套筒连接的施工便利性，在已研发的内径大、施工方便的Ⅰ和Ⅲ型套筒灌浆搭接连接的基础上，进行了1片现浇剪力墙和2片纵筋采用Ⅰ与Ⅲ型套筒搭接连接的预制剪力墙拟静力试验.结果如下，现浇墙初始裂缝出现在墙底部，而预制墙由于套筒竖向约束，初始裂缝出现在套筒上方，预制墙开裂荷载大于现浇墙；在极限状态时，现浇墙两侧根部混凝土压碎，而预制墙套筒上方混凝土先压碎，后套筒外侧混凝土保护层局部脱落而破坏；预制墙开裂、屈服荷载、极限位移大于现浇墙，极限承载力与现浇墙的基本相同，但延性略差；由于套筒区域边缘构件箍筋及墙身水平钢筋的加密，预制墙的耗能略优于现浇墙；钢筋应变曲线一致性表明，Ⅰ和Ⅲ型套筒在预制混凝土剪力墙中能够很好地传递钢筋应力.

Abstract:

To investigate the seismic behavior of grouted sleeve lapping connector, pseudostatic experiments were conducted on a castinplace shear wall and two different precast shear walls in which longitudinal reinforcement were connected by typeⅠand typeⅢgrouted sleeve lapping connector respectively. Initial crack appeared at the bottom of the castinplace shear wall, while for the precast shear walls, the initial crack appeared above the sleeve due to the vertical confinement of sleeve, and the cracking load of the precast wall was greater than the castinplace wall. At the ultimate stage, concrete were crushed at the root of the castinplace shear wall; the concrete cover around the sleeve peeled locally and then was destroyed, following the crush of the concrete above the sleeve in the precast shear walls. The ultimate bearing capacities of the two different types of shear wall were almost same. Compared to the castinplace shear wall, the cracked degree, yield load and ultimate displacement of the precast shear walls were larger, the ductility of the precast shear walls was a little lower. Due to the densification treatment of the horizontal bars in wall body and the stirrup of rim member in the region of sleeve, the energy dissipation of the precast shear walls was better than that of the castinplace shear wall. The strain curve of the steel bar above and below the sleeve is consistent, which shows that both typeⅠand type Ⅲ grouted sleeve lapping connectors performed well in transferring the stress of the steel bar.