大跨连续刚构桥-船撞击动力响应研究

Study on Dynamic Response of Long-span Continuous Rigid Frame Bridge - Ship Collision

摘要:

本文以某高速公路新建连续刚构桥为工程背景,采用非线性有限元分析方法,通过大型通用非线性有限元程序LS-DYNA建立全桥有限元模型和1000t船舶模型,对船-桥碰撞动力过程进行模拟,以确定船-桥碰撞过程中碰撞力的大小,并将有限元计算结果与规范经验公式进行比较。结果表明：船-桥碰撞过程中,船艏发生较大变形,吸收大部分的能量,将动能转化为势能；碰撞过程具有明显的非线性波动特征；各个规范经验公式计算的船撞力差异较大,且规范经验公式具有一定的局限性,有限元分析法能完整再现船-桥碰撞结构内部动力学过程,弥补规范经验公式的不足。

Abstract:

Taking a new continuous rigid frame bridge of an expressway as the engineering background, the nonlinear finite element analysis method is used to establish the full bridge finite element model and the 1 000 t ship model through the large-scale general nonlinear finite element program LS-DYNA. The dynamic process of ship-bridge collision is simulated to determine the magnitude of the collision force in the process of ship-bridge collision, and the results of finite element calculation are compared with the normative empirical formula. The results show that in the process of ship-bridge collision, the bow of the ship is deformed greatly, which absorbs the most of the energy, and the kinetic energy is converted into potential energy. The collision process has the obvious nonlinear fluctuation characteristics. The ship collision force calculated by each normative empirical formula is quite different, and the normative empirical formula has certain limitations. The finite element analysis method can completely reproduce the internal dynamic process of the ship-bridge collision structure and make up the deficiency of the normative empirical formula.