矩形钢管混凝土桁架静力性能非线性有限元分析

Nonlinear Finite Element Analysis on the Static Behavior of Rectangular Concrete-Filled Steel Tubular Truss

为了研究矩形钢管混凝土桁架的静力性能和分析模型,采用非线性有限元法,建立了两种不同的杆系模型,并将分析结果进行比较.结果表明:单材料模型对矩形钢管混凝土桁架的分析结果较为可靠,但材料本构关系成为有限元分析的关键;矩形钢管混凝土桁架的破坏并不是杆件造成的,而是由节点失效引起的,且失效将发生在相对变形量较大的节点位置;分析所得极限承载力为桁架节点发生塑性变形时荷载值,与桁架整体极限承载力稍有偏差,但分析模型能够满足桁架在桥梁结构中的设计要求.

In order to study the static behavior and finite element model of rectangular concrete-filled steel tubular truss,two analysis models were built with nonlinear finite element method,the ultimate bearing capacity were analyzed and the results of two different analysis models were compared.The results show that the single material model was more effective than the double material model,but the constitutive relationship became the critical factor;the failure of rectangular concrete-filled steel tubular truss was caused by the points of truss not the chord pipes;and there was some deviation between textual results and actual results on the ultimate bearing capacity,but the results can meet the design requirements in bridge structure.