GQJS在波形钢腹板连续箱梁桥施工过程计算中的应用

Application of GQJS in Calculation for Construction Process of Continuous Box Girder Bridge with Corrugated Steel Webs

为研究波形钢腹板组合箱梁的变形特点,以山东鄄城黄河公路大桥为工程依托,基于桥梁结构分析软件GQJS采用了两种单元离散方式进行该桥的施工过程分析。方法1简称"1节点法",即顶底板混凝土和中间钢腹板单元共用节点,顶底板挠曲变形符合平截面假定,并用平钢板代替波形钢腹板,为考虑波形钢腹板褶皱效应,将波形钢板Q345钢材的弹性模量按轴向刚度等效的方法进行折减。方法2简称"2节点法",即顶底板混凝土单元节点独立,由钢腹板连接顶底板单元,顶底板挠曲变形不符合平截面假定,可以有相对位移,波形钢腹板控制上下节点相对位移。研究结果表明:采用1节点法和2节点法所得变形计算结果相差不大,并且都与实测结果相吻合,证明这两种单元离散方式均是可行的。

In order to study the deformation features of box girder with corrugated steel webs, based on the project of Juancheng Yellow River Highway Bridge, two element-modeling methods were adopted to perform finite element analysis throughout the construction process by Highway Bridge Design Analysis Software （ Chinese name abbreviation ： GQJS）. In the first method （ One-node Method for short）, elements of top and bottom concrete slabs as well as steel webs share the same nodes, agreeing with the assumption of plane section. And plain steel webs are adopted instead of corrugated steel webs. In order to take into account the accordion effect of corrugated webs, the reduction elastic modulus of Q345 steel is determined according to equivalent axial stiffness. In the second method （ Two-node Method for short）, nodes of elements of top and bottom concrete slabs are independent relatively and elements of corrugated steel webs connect with elements of top and bottom concrete slabs. In this case, relative displacement is allowed between the top and bottom concrete slab elements, not agreeing with the assumption of plane section, and the relative displacement between top and bottom concrete slab nodes are controlled by elements of corrugated steel webs. The results show that there is no great difference in terms of deformation value adopting either One-node Method or Two- node Method and the numerical results of the two methods are in good agreement with measured results, which indicates that the two modeling methods are feasible.