部分充填钢箱-混凝土组合梁受力性能有限元分析

Finite Element Analysis of Mechanical Performance of Partially Filled Steel Box-Composite Beams

为了研究部分充填钢箱-混凝土组合梁负弯矩区的受力性能,完成3根简支组合梁构件在跨中两点反向对称荷载作用下的试验.选用合适的单元类型、本构关系及破坏准则,建立以模拟试验梁为对象的非线性模型,得到相应的挠度-荷载曲线和截面应变值,模拟结果与试验结果吻合良好.通过改变梁的一些主要参数,对极限承载力和跨中挠度进行预测.分析表明:若要提高极限承载力和降低跨中挠度,可依次提高梁的配筋率,加厚底板、腹板、顶板和中隔板,也可适当提高混凝土强度.

The mechanical performance of partially filled steel box-concrete composite beams was investigated by the experiment of three simple-supported composite beam components under mid-span two-point antisymmetric loads.Suitable element types,constitutive relationship and failure criterion were selected to establish a nonlinear model to simulate the experimental beams.The deflection-load curves and cross-sectional strain values were obtained.The simulation results agree with the obtained experimental results,indicating the validity of finite element model.The bearing capacity and the mid-span deflection can be predicted by some of the major beam parameters.The analysis indicates that the ultimate load bearing capacity and stiffness of beams enhance as reinforcement ratio of girders,thickness of baseboard,web,roof,partition and concrete strength increase.