竖向预应力对一座变截面连续箱梁桥简支端的主应力影响分析

箱梁截面的刚度大,整体性好,既能承受正弯矩,又能承受负弯矩,为一种性价比较好的截面型式。但近年来发现部分箱梁简支端附近腹板有开裂现象,个别较严重。本文以一座预应力混凝土变截面连续箱梁桥为例,通过空间有限元数值仿真分析计算,发现竖向预应力对箱梁腹板主拉应力影响较大。

Vertical Pre-stress Influence to Principal Stress of Simply Supported End at the Variable Cross-section Continuous Box Girder Bridge

Box girder cross section is a cost-effective section due to its large stiffness, and can withstand both the negative and sagging bending moment. But part web of the box girder near the simply supported end often cracks in recent year. In this article, simulations were carried base on a typical variable cross-section continuous box girder bridge. Results showed that vertical per-stress has large influence to the prin-cipal tensile stress of the web.