基于概率有限元的船撞薄壁高桥墩可靠性分析

摘要

目的 对大跨径连续刚构桥薄壁高墩施工期间船撞荷载作用下进行可靠性计算及敏感性分析,得到薄壁高墩在船撞荷载下的可靠概率.方法 采用ANSYS有限元软件提供的APDL语言与求解可靠度的Monte-Carlo法相结合,通过对随机输入变量的抽样,对船舶撞击薄壁高墩进行可靠性计算,并对设计参数进行敏感性分析.结果 在置信度为95%时,薄壁高墩在船撞荷载作用下的可靠性为100%;船撞荷载的变异性对最大应力的相关系数最大为0.2916.结论 利用Monte-Carlo法中的拉丁超立方抽样方法计算桥梁的可靠度能够真实反映出桥梁的可靠性,该方法具有较高的效率和使用价值.%This paper aims at analyzing the reliability and sensitivity of ship collision with thin-walled high pier during the span continuous rigid frame bridge construction. And the structural failure caused by the potential risk can be calculated. Combined the APDL language in the finite element software ANSYS with Montecarlo method about reliability solution, the reliability of ship against thin-walled high pier was calculated and the parameters' sensitivity was analyzed through the sampling of random input variables. In the confidence level of 95％ ,the reliability of the thin-walled high pier with ship collision loads is 100％. And the variation of ship collision loads on the correlation coefficient of maximum stress is 0.2916, which is the biggest. The reliability of the bridge calculated by Latin hypercube sampling method of Montecarlo method can reflect reliability of the bridge truly. The method has high efficiency and value.