基于Pushover理论的钢管混凝土构件塑性铰特性值研究

Research on Plastic Hinge Property of Concrete-filled Steel Tubular Members Based on Pushover Theory

Pushover理论广泛应用于结构弹塑性地震分析,也可用于结构极限承载力和失效薄弱点分析.根据钢管混凝土构件统一理论的弯矩—曲率关系,对构件弹塑性状态下截面的弯矩—转角关系进行推导,提出构件M铰和PMM铰特性值的计算方法.根据钢管混凝土简支桁梁结构模型的试验结果,对提出的实用计算方法进行可行性验证.研究结果表明:钢管混凝土构件塑性铰特性值的确定方法是合理的,对钢管混凝土桁梁极限承载力的分析是可信的,为从宏观上掌握大型钢混组合桁架梁桥在弹塑性阶段静、动力性能提供了有效的理论基础和研究手段.

Pushover theory has not only been widely used in elastic seismic analysis of the structure, but also can accurately describe ultimate bearing capacity and failure of weak point of the structure. According to the relationship between moment-curvature of concrete filled steel tubular members based on the unified theory, the moment-rotation relationship in elastic-plastic state is deduced, and the calculation method of M hinge and PMM hinge properties are put forward. Based on the test results of simply-supported girder with concrete filled steel tubular truss, the feasibility of proposed practical calculation method is verified. The comparison results show that the calculation method to determine plastic hinge properties of concrete filled steel tubular members is reasonable, and the analysis on the ultimate bearing capacity of CFST Truss Girder is credible, which pro- vides an effective theoretical basis and research methods to grasp the large steel-concrete composite truss bridge in elastic-plastic stage static and dynamic performance.