钢-混凝土组合悬臂梁施工稳定性分析

用ANSYS非线性有限元程序,结合重庆某正在施工的钢-混凝土组合连续刚构桥,对钢-混凝土组合悬臂结构在不同施工阶段,不同施工步骤的第1阶屈曲模态及特征值进行了数值模拟研究。结果表明:翼缘板对整个组合结构的稳定性作用不大,但提高了腹板的稳定性;加劲肋提高了钢-混凝土组合结构整体的稳定性,并且其作用不受跨径变化的影响。横隔板在跨径较小时,发挥的作用远超过加劲肋,随着跨径增大,其作用迅速降低;混凝土由于自重太大,对组合结构的稳定作用不大,若施加部分过长,对结构的稳定将起副作用。

Construction Stability Analysis of Steel-concrete Composite Cantilever Beam

The authors investigate the first-order buckling mode and eigenvalue of steel-concrete composite cantilever beam under different construction stages and steps.A continuous rigid frame bridge,which has steel-concrete composite section and are under construction in Chongqing is analyzed by using finite element program ANSYS.The results show that: flange has little use to the whole structure stability,but can increase the stability of the web.Stiffeners can increase the overall stability of the composite box and it does not change with span changes.The stability role of diaphragm greatly exceed stiffeners when the span is small,with span increasing,its role rapidly reduce.Because of too much weight,the concrete plays a minor role to the stability of the composite structure,if the applied part is too long,it would play adverse role.