拓宽及提载对空心板桥旧板受力影响分析

Stress Analysis of Old Slabs in Widened Hollow Slab Bridges with New Live-load Grade

公路拓宽工程在我国随着交通量的增长屡见不鲜,且随着交通荷载的变化,进行拓宽的同时往往要考虑其能否满足新的汽车荷载等级要求并进行适当改造。在我国运营的中小跨径桥梁中,空心板桥数量庞大,空心板桥拓宽连接接缝的连接方式及刚度对荷载的横向分布系数变化影响已有不少研究,而综合考虑横向分布系数变化及汽车荷载变化的影响更具有实用价值。因此,以某高速公路拓宽工程为背景,选取一批有代表性的空心板桥开展拓宽分析,研究不同跨径旧桥拓宽后横向分布系数的变化,并综合考虑汽车荷载等级提高引起的空心板活载内力变化,判断其改造的必要性,为类似工程的拓宽改造提供参考。

Highway widening project is common in China with the increase of traffic volume, and with the increase of traffic load, it is often necessary to consider whether it can meet the new demand of live load so as to improve the service level. There are a large number of hollow slab bridges with small or medium span in China.There has been lots of research on the influence of the connection mode and stiffness of the widening joint on the change of the transverse distribution factors. Considering the variation of transverse distribution coefficient and the variation of live load, the variation of stress is necessary to be researched. Therefore, taking a highway widening project as the background, some representative hollow slab bridges were selected to carry out the widening analysis, to study the change of the transverse distribution coefficient after widening. Taking into account the change of the live load grade of the bridges and widening effect, the stress of hollow slabs were discussed, so as to provide a reference for the widening and reform of similar projects.