公路交通桥头跳车成因探讨

Research on the Causes of Bump at Bridge- head in Highway Traffic

对某市40座现有桥梁桥头损伤进行了调查,结果表明35%以上的桥头存在中等以上跳车现象。用有限元软件对桥头路基建模分析表明,桥头后背填土与路面结构间存在脱空,埋设压力盒对桥头路基应力的监测表明桥头后背填土横向应力随路面荷载增大而减小,说明桥台结构和桥台后背填土间存在分离现象,造成路面结构在桥台处弯曲破坏,形成开裂和沉陷,引起车辆通过时发生跳车。

Investigations on the bridge- head damage of 40 bridges in one city show that there exist bumping phenomenon in more than 35 % of bridges. The bridge - head subgrade modeling analyses by using finite element software show that there exist cavities between bridge - head back fill and mad surface structure. The stress data of bridge - head subgmde monitored by the buried pressure cells shows that the transverse stress of bridge- head hack fill decreases with the increase of the road load, which means that there exist cavities between abutment structure and abuunent back fi11, bringing about mad surface structure bending destroy around the abutment, forming crack and sinking and causing bumps when ears pass.