变截面预应力混凝土箱梁桥结构计算与病害分析

Structural calculation and disease analysis of the section changeable PC continuous box-girder bridge

为了验证变截面预应力混凝土箱梁桥的病害产生原因,实地随机调查交通量并确定三种典型荷载工况,用有限元软件建立了梁桥模型并进行了结构计算分析。研究结果表明:超载是该桥产生箱梁底板横向开裂的主要原因,竖向预应力失效导致腹板内侧开裂严重,纵向预应力钢束定位偏差易导致底板混凝土分层劈裂。

In order to verify the cause of disease of the section changeable PC continuous box-girder bridge,a field survey was carried out randomly to determine the traffic volume. Then confirmed three typical load conditions. Finally,a bridge mode was established with the finite elements software and applied the structure analysis and calculation. The results show that the overloading is the main reason for the transverse cracking of the bottom plate of the bridge,the failure of vertical pre-stress cause the inside of the abdominal plate to crack badly,and the positioning deviation of longitudinal pre-stressed steel beam is easy to split the bottom slab concrete.