钢栈桥桩顶梁截面ANSYS简化对其力学性能的影响

Influence of ANSYS-based simplified top beam cross-section form of the steel trestle pile on its mechanical properties

为了研究钢栈桥桩顶梁截面形式在ANSYS中简化后对其力学性能的影响,以黄河大桥施工栈道桩顶梁为研究对象,利用ANSYS建立原始模型和简化模型,首先分析静力作用下两者应力的差异,然后分析风荷载作用下施工栈道动力响应的差异。结果表明:(1)在上部结构自重作用(静力作用)下,两者最大竖向位移相差仅为0.56%,米塞斯应力相差仅为0.68%;(2)在风荷载作用(动力作用)下,两者桩顶梁中部节点最大速度绝对值相差0.023%,最大加速度绝对值相差0.2%。在上部结构自重作用或者风荷载作用下进行钢栈桥受力分析时,可用简化截面代替原截面进行计算。

In order to investigate the influence of the ANSYS-based simplified top beam cross-section form of the steel trestle pile on its mechanical properties,an original model and a simplified model in the ANSYS software were built with the top beam of the construction trestle pile at the Yellow River Bridge as the research object.Firstly,differences in stresses acted on these two models under the static force were elaborated,then,the comparison of dynamic responses of the construction trestle under the wind load were analyzed.The results showed that:(1)Under the self-weight of the upper structure(static action),two models slightly differ from each other in the maximum vertical displacement(only 0.56%)and the Mises stress(only 0.68%);(2)Under the wind load(dynamic action),there was a difference of 0.023%in absolute values of the maximum velocity of the middle part of the pile top beam among two models,and there was also a difference of 0.02%in absolute values of the maximum acceleration.Therefore,it was feasible to use the simplified cross section to represent the actual cross section in the research on the stress analysis of the steel trestle under the self-weight of the upper structure or the wind load.