剪切-粘结破坏是钢筋混凝土结构的一种重要震害形式,为研究剪跨比在1.5―2.5之间钢筋混凝土柱的抗震性能,进行了16个试件的拟静力试验,对其破坏形态、延性及耗能能力、刚度退化、抗剪承载力等进行了对比分析。结果表明,试件以剪切及粘结破坏为主,可分为弯剪、剪切和粘结破坏三种类型,弯剪破坏试件表现出较好的延性和耗能能力,而粘结破坏试件滞回曲线表现出明显的"捏拢"效应,延性及耗能能力差、刚度退化快,为脆性破坏,易发生于剪跨比λ在1.5―2.0,受拉纵筋配筋率≥1.0%且混凝土强度较低的框架短柱中,宜在抗震设计中引起重视。
Shear-bond failure is an important failure mode for reinforced concrete(RC) structures subjected to seismic actions.The quasi-static test for 16 specimens with the aspect ratio between 1.5―2.5 was conducted to study the aseismic performance of RC columns.The failure patterns,ductility and dissipated energy parameters,degradation of stiffness and shear strength of the specimens are studied.The test results indicate that the specimens were dominated by shear and bond failure,including flexural-shear,shear and bond failure modes.The specimens with flexural-shear failure show good ductility and energy dissipating capacity,while the specimens with bond failure have clearly "pinching effect",poor ductility and energy dissipating capacity and faster stiffness degradation,which leads to a non-ductile behavior of the specimens.Also,short columns with aspect ratios between 1.5―2.0,tensile longitudinal reinforcement ratios exceed 1.0% and low concrete strength were vulnerable to bond failure,on which more attention should be paid in aseismic design.