钢箱—混凝土组合梁受力性能有限元分析

Finite element method analysis of performance of concrete-filled steel box girder

钢箱—混凝土组合梁是一种新型钢—混凝土组合结构。为研究钢箱-混凝土组合梁的结构性能,分析其强度和刚度的主要影响因素,在ANSYS软件中利用板壳单元和实体单元建立了梁的三维空间有限元模型,考虑材料非线性和钢板局部屈曲的几何非线性,对钢箱-混凝土组合梁受力行为进行了有限元分析,分析结果与试验实测结果吻合良好,说明计算模型有效。利用计算模型对影响钢箱—混凝土组合梁强度和刚度的主要参数进行了分析,结果表明,钢板厚度变化对梁的强度和刚度的影响强弱依次为底板>腹板>顶板,提高混凝土强度可以明显提高梁的强度和刚度。

Concrete-filled steel box girder is a new type of steel-concrete composite structure. In order to investigate the behavior of concrete-filled steel box girder and the main affecting factors of its ultimate strength and stiffness, three-dimensional models of the girder were established by ANSYS software using shell elements and solid elements. With the geometric and material nonlinearities taken into consideration, the mechanical behavior of the girder was analyzed and the calculated resuits agreed with the test results well. The effects of the main parameters on the strength and deflection of the girder were analyzed using the model. The results indicated that bottom plate thickness had more influence on the strength and stiffness of the girder than web thickness, while top plate thickness had the least influence. The rise of concrete strength can enhance the strength and stiffness of the girder obviously.