叠合整体式混凝土剪力墙轴心受压性能研究

Study of integral composite reinforced concrete shear wall subjected to axial loading

通过对1个现浇和7个叠合整体式混凝土剪力墙足尺试件的轴心受压试验,考察了其在轴心荷载作用下的受力性能、破坏模态和承载力,分析高厚比、预制部分截面面积占全截面面积比例(预制率)和预制薄板板肋方向等因素对剪力墙试件轴心受压性能的影响。结果表明,叠合整体式混凝土剪力墙破坏模态分为叠合面开裂破坏和轴心受压破坏两种:叠合面开裂破坏前,有明显的开裂现象,破坏过程平缓,试件承载力较低;轴心受压破坏前,试件表面无明显的裂缝产生,破坏过程突然,承载力较高。墙体高厚比对试件的承载力影响不明显;预制率越高,压缩刚度越大,墙体竖向变形越小;预制薄板板肋对叠合墙受压性能影响较小。针对叠合整体式混凝土剪力墙轴心受压破坏模态,总结中、美两国规范及已有研究中的轴心受压构件承载力计算公式,给出了叠合整体式混凝土剪力墙的轴心受压承载力简化计算式,其计算值与试验值吻合较好。

To study the axial compressive performance of integral composite reinforced concrete shear wall（ CSW）, the mechanical properties, failure mode, and bearing capacity under axial load were investigated. The influences of the height-thickness ratio, proportion of the prefabrication area to the gross area concrete （ prefabrication rate ） and the direction of ribs located at the prefabricated slab on the performance of specimens were analyzed through axial compression full-scale tests on one cast-in-situ shear wall and seven integral composite reinforced concrete shear walls. The results show that the failure modes of CSW are cracking failure at composite surface and axial compression failure. Before the cracking failure at composite surface, there is an obvious cracking phenomenon. The damage process is slow and the load bearing capacity of specimens is low before failure; before the axial compression failure, the specimen surfaces have no apparent cracks. The failure process is quick and the load bearing capacity is high. The height- thickness ratio has little effect on the load bearing capacity of the CSW; the increase of the prefabrication ratio can result in higher compression stiffness and smaller vertical deformation of CSW ; the direction of rib in prefabricated slab has little impact on the compressive properties of CSW. Based on the compressive failure pattern and the calculation formulas for the load bearing capacity of the axial compression member from the Chinese and American codes and available research, the simplified calculation formula for the integral composite reinforced concrete shear wall subjected to axial load is given, and the calculated and experimental results agree well.