基于单板受力的预应力混凝土空心板桥承载力评定

Evaluation of Load-bearing Capacity of Pre-stressed Concrete Hollow Slab Based on Single Slab Load Bearing

为了研究处于"单板受力"状态桥梁的承载能力,采用已使用10 a的旧桥预应力混凝土空心板的试验数据,对既有空心板桥的承载力状况进行了评定。分别基于荷载横向分布和单板受力模式进行抗力-荷载效应分析,以确定既有桥梁的承载力。结果表明,"单板受力"削弱了上部结构的整体作用,降低了桥梁的整体承载力,使得上部主要承重构件处于非常不利的受力状态,降低了结构的耐久性和安全性。用现有承载力评定方法对处于"单板受力"状态的桥梁进行承载力评定,为既有不利状态的空心板桥的承载力评估提供很大的参考价值。

In order to research the load-bearing capacity of pre-stressed concrete hollow slab in single slab load bearing state, the load-bearing capacity of existing hollow slab bridge is evaluated based on the test data of the pre-stressed concrete hollow slabs which have been used for 10 a. The resistance-load effects based on load transverse distribution and single slab load-bearing mode are analysed separately to determine the load- bearing capacity of the old bridge. The result shows that the single slab load bearing weakened the whole reliability of the superstructure and the whole bearing capacity of the bridge, which led to the supporting part of the superstructure in the adverse state and decreased the structural durability and safety. The load-bearing capacity of the bridge in single slab bearing state is evaluated using the existing evaluation method, which can provide reference value for evaluating the load-bearing capacity of the old unfavorable concrete hollow slab bridge.