南平西城大桥预应力混凝土箱梁预拱度有限元分析

FINITE ELEMENT ANALYSIS OF PRE-CAMBER OF NANPING XICHENG PRE-STRESSED CONCRETE BRIDGE

南平西城大桥是大跨度预应力混凝土变截面连续刚构桥,其连续刚构采用挂篮悬臂现浇法施工,在各箱梁节段施工时需要设定预拱度。本文使用MIDAS/Civil有限元软件,采用正装方法计算并分析了西城大桥箱梁各节段施工过程的预拱度。对挂篮中的箱梁节段自重引起的施工荷载,已发表的相关论文采用等效力和力矩计算,本文则直接根据挂篮中箱梁节段及挂篮的平衡条件进行处理,对计算所得预拱度的分析表明本文的处理方法是正确的。

As a large-span pre-stressed concrete continuous rigid frame bridge, Nanping Xicheng Bridge is constructed using cantilever form traveler, whose box girder segments must be pre-cambered during construction. In this paper, the pre-cambers of the box girder segments of Xicheng Bridge are computed and analyzed using MIDAS/Civil finite element software. In relevant papers, equivalent forces and moments are employed to describe construction loads caused by the box girder segments in the form traveler. Equilibrium equations of the form traveler and the box girder segments are directly utilized to obtain the construction loads in this paper, numerical results of the pre-cambers reveal that this paper’s method is correct and effective.