简支变连续箱梁连续端合理受力影响分析

某特大桥上部结构为整体预制单箱双室斜腹板预应力混凝土箱梁,为使其在存放及简支等阶段连续端合理受力,并满足大型浮吊吊装能力等要求,采用有限元软件Ansys,建立空间实体计算模型,比较分析横隔板构造形式、临时支座布置间距及方式、预应力等对箱梁连续端位移及应力的影响。研究表明,箱梁连续端预制全横隔板,在中腹板位置底板下部亦布置临时支座时,箱梁端部变形平缓,抗裂性得到提高。

Mechanical Effect Analysis for Continuous Section of Simply-Supported Continuous Box Girder

In a super major bridge, precast PC box girder with single-box and double-cell inclined webs is used in the super- structure. In order to rationalize the mechanic status in storage and simply supported condition and to meet the lifting require- ments, the finite element software ANSYS is used to build 3D solid model, which focuses on the influence of diaphragm structure, temporary support arrangement distance and prestress tendons on stress and deformation of continuous section. Study shows that if the diaphragm is set on the continue section, and the temporary support is arranged on the inner web, the deformation curve is smoother and the cracks are thinner.