超高性能混凝土预制板-叠合剪力墙抗震性能研究

Study on seismic behavior of ultra-high performance concrete composite shear wall with precast slab

通过对1片现浇混凝土剪力墙和4片超高性能混凝土(ultra-high performance concrete, UHPC)预制板-叠合剪力墙抗震性能试验,研究了其滞回性能、抗弯承载力、延性、刚度和耗能能力等指标,分析了高宽比、聚乙烯泡沫(expanded polystyrene, EPS)芯模置换和竖向钢筋连接方式对其抗震性能的影响。结果表明:与现浇混凝土剪力墙相比,UHPC预制板-叠合墙具有优异的抗震性能,最大受弯承载力增大;UHPC预制板和钢筋桁架可较好地与空腔内现浇混凝土协同工作;UHPC叠合墙的滞回曲线、骨架曲线和刚度退化曲线与现浇混凝土剪力墙趋势基本一致;在本试验剪力墙的高宽比范围内,高宽比越小,UHPC预制板-叠合墙的受弯承载力和刚度越大,耗能越差;EPS芯模置换可提高叠合剪力墙屈服后的耗能能力,降低了UHPC叠合墙的延性;仅采用暗柱竖向钢筋与底座进行连接,对UHPC叠合墙的受弯承载力和耗能影响较小,但却可以很大程度方便施工。

Based on the seismic performance test of one common shear wall and four ultra-high performance concrete(UHPC)prefabricated composite shear walls,the hysteretic properties,bearing capacity,ductility,stiffness,and energy dissipation capacity were studied.The effects of width-to-height ratio,replacement by expanded polystyrene(EPS)and vertical reinforcement connection on the seismic performance were analyzed.The results show that compared with the common shear wall,the UHPC composite wall has excellent seismic performance and the maximum bending capacity increases.The UHPC prefabricated slab and steel truss can work well with the concrete in the cavity.The hysteretic curve,skeleton curve and stiffness degradation curve of UHPC composite wall are basically consistent with the trend of common shear wall.In the range of the ratio of height to width,the smaller the ratio of height to width,the greater the flexural capacity and stiffness of the composite wall of UHPC,and the worse the energy dissipation.Replacement by EPS can improve the energy dissipation capacity of composite shear wall after yield,but reduce the ductility of UHPC composite wall.Only using the vertical reinforcement of the concealed column to connect with the base has little effect on the flexural capacity and energy dissipation of the UHPC composite wall,but it can facilitate the construction greatly.