钢筋混凝土/ECC组合梁-柱节点抗震性能的试验研究

摘要

高延性纤维增强水泥基复合材料（ECC）是一种具有应变硬化特性和多裂缝开展机制的新型建筑材料。对于钢筋混凝土构件,用ECC材料代替混凝土能够有效提高构件的强度和延性性能。文章对普通钢筋混凝土梁-柱节点和钢筋混凝土/ECC组合梁-柱节点构件进行了低周反复加载试验研究。结果表明：对于节点区未配箍筋的节点构件,在节点区用ECC材料代替混凝土能够显著提高构件的承载力、变形及延性性能;钢筋混凝土/ECC组合梁-柱节点构件的抗震性能比在节点区配置箍筋的钢筋混凝土节点也要更优越。%Engineered cementitious composites(ECC) are a class of high-performance fiber reinforced cement composite with strain hardening and multiple cracking properties.For a reinforced concrete member,substitution of conventional concrete with ECC can significantly improve the deformation characteristics in terms of reinforced composite tensile or shear strength and energy dissipation ability.In this paper,a number of RC/ECC composite beam-column joints have been tested under reversed cyclic loading to study the effect of substitution of concrete with ECC in the joint zone on the seismic behaviors of composite members.The experimental parameters include shear reinforcement ratio in the joint zone and substitution of concrete with ECC or not.According to the test results,for the specimens without shear reinforcement ratio in the joint zone,substitution of concrete with ECC in the joint zone can significantly increase the load capacity and ductility of the beam-column joint specimens,as well as the energy dissipation ability due to high ductility and shear strength of ECC material.The load-deformation response of RC/ECC composite beam-column joints without stirrups is more superior than the normal reinforced concrete beam-column joint with congested stirrups.