高强箍筋高强混凝土柱抗震性能研究

为研究高强箍筋高强混凝土柱的抗震性能,首先进行了6根配置高强箍筋的高强混凝土柱和3个普通强度混凝土柱(作为对比)抗震拟静力试验,并对其破坏形态、滞回曲线、延性及耗能指标以及抗剪强度等进行了对比分析。结果表明:高强混凝土试件与普通混凝土试件破坏过程相似,均呈弯剪破坏形态,采用高强混凝土可有效降低试件轴压比,对其延性和耗能能力有利。将国内外进行的高强箍筋高强混凝土柱抗剪承载力试验结果与美国ACI318规范、我国混凝土结构设计规范(GB50010-2002)的抗剪公式进行了对比,认为ACI规范及我国规范在计算高强箍筋高强混凝土柱抗剪承载力时均有不安全因素,宜在设计时注意。采用Mander建议的约束混凝土本构关系和纤维单元程序USC_RC仍可以对高强箍筋高强混凝土柱的受弯承载力进行较为准确的模拟分析。

RESEARCH ON THE SEISMIC PERFORMANCE OF HIGH-STRENGTH CONCRETE COLUMNS WITH HIGH-STRENGTH STIRRUPS

Reversed cyclic loading tests for 6 high-strength concrete (HSC) columns and 3 normal strength concrete (NSC) columns (for comparison) are conducted to evaluate the seismic behavior of HSC columns with high-strength stirrups (HSS). The failure patterns,hysteretic curves,ductility and dissipated energy parameters and shear strength of the specimens are studied and compared with each other. It is found that the failure patterns of the HSC columns are similar with NSC columns and all of them suffered flexural-shear failure modes. HSC concrete will decrease the axial load ratio of the column,which will be beneficial for the ductility of the columns. The shear strength of HSC columns with HSS are compared with ACI 318 and GB 50010-2002 codes,it is founded that both the codes would overestimate the shear strength of the columns and one should pay more attention in the design. The fiber element software USC_RC based on Mander model for confined concrete could also be used to simulate the flexural strength of HSC columns with HSS.