宽幅单箱多室箱梁受力特性分析

本文阐述了宽度达33m单箱多室箱梁桥的施工期受力分析。主要对箱梁中线位置及悬臂翼缘处竖向位移沿纵桥向的分布、箱梁横桥向位移分布特征、箱梁应力的横桥向分布情况进行了分析。计算显示，即使在施工期、仅考虑恒载的作用下，宽幅单箱多室箱梁的横桥向变形和应力分布在翼缘和中心线处存在较大差异。研究表明，宽幅单箱多室箱梁桥横向受力情况复杂，在设计中仅采用杆系有限元程序进行计算并不能全面揭示其受力特性；施工中应采取有效措施，避免箱梁复杂应力导致混凝土出现开裂等情况。

Analysis of Deformation and Stress Characteristics of Single Box Girder with Large Width and Multiple Cells

Deformation and stress of single box girder, 33m in width with multiple cells was analyzed. The vertical deformation at the wings and the center of box girder, deformation and stress in girder section were discussed. The calculating results show that during its construction, the box girder has different deformation and stress at the wings and the center in its section. Thus it could be concluded that the wide box girder was in complex stress condition and it should be calculated not just by bar system finite - element method. Since complex stress could cause cracks in girder concrete after it was used to carry moving loads so that measures should be taken to avoid it.