刚果（布）Loukouni桥施工过程仿真分析

摘要

Loukouni桥是刚果（布）1号公路Ⅱ期工程中的一座采用缆索吊装的上承式钢箱拱桥，为保证其施工过程的安全性，用零弯矩法、零位移法和定长扣索法，分别获得了施工过程中扣索索力和拱肋预抬值，并利用通用有限元软件ANSYS的生死单元功能对施工过程进行了仿真分析。计算结果表明：定长扣索法和零位移法确定的施工方案均能满足拱肋线形、施工截面应力和变形控制的要求，定长扣索法更优，可以作为该桥施工首选的设计方案；试算零位移法是确定施工扣索索力的一种简便有效的方法。%Loukouni bridge is a deck type arch bridge with box section and is a part of the second stage of the first national road project of the Republic of Congo. This bridge will be constructed with cable erecting equipment. To make sure its construction safety,three methods,including the zero moment method,the zero displacement method and the invariable cable method,were used to calculate the cable force of fastening cable and the pre-camber of main arch during the construction. Live and dead elements provided by the general FE (finite element)software ANSYS were utilized to simulate the construction of the bridge. The research result shows that both the zero displacement method and the invariable cable method can meet the construction demand in terms of the shape of the arch,the stress of arch section and the deformation of the arch. In the two methods,the invariable cable method is better and should be the first choice applied to the Loukouni bridge. The trial zero displacement method is a simple and effective way to obtain the cable force.