基于车桥耦合振动的空心板桥铰缝损伤评价指标分析

铰缝损伤是装配式混凝土空心板桥的典型常见病害,研究基于交通荷载下结构动力响应的铰缝损伤判别方法,将大幅降低检测耗时和费用。以典型桥例,应用自编的车桥耦合振动分析程序,针对多种典型的铰缝损伤工况,采用数值方法系统地分析了铰缝损伤对车载下桥梁动力响应的影响。结果表明铰缝损伤对桥梁跨中动力响应峰值及其横向分布有明显影响。通过对损伤前后桥梁动力响应变化特征的量化分析,提出了铰缝刚度和加速度幅值比两个铰缝损伤的评价指标,并通过算例进行了初步分析验证。研究结果可为空心板桥铰缝损伤检测与评价提供一种新的技术思路。

Evaluation Index of Hinged Joint Damage For Simply Supported Multi-Slab Girder Bridges Based on Vehicle and Bridge Coupled Vibration

The hinged joint damages is a kind of multiple disease forms for concrete fabricated hollow slab bridge, so the damage identification method to hinged joint based on structural dynamic response under traffic load is significant to reduce the testing time and expense. According to some typical bridges cases, the numerical analysis on the effect of hinged joint damages on the vehicle-induced dynamic response of bridges will be carried out in the present study which based on the program of train-bridge coupling vibration and combined with a variety of typical joint damage conditions. The results show that the joint damage has obvious influence on the peak value of the dynamic response to the middle of bridge span and the transversal distribution of the bridge. In this study, the joint stiffness and the acceleration amplitude ratio are proposed to evaluate the hinge joint damage by quantifying the dynamic response characteristics of the bridge before and after the damage, at the same time, the preliminary analysis and verification are carried out by some examples. The research results provide a new technology useful reference for joint damage detection and evaluation based on the vehicle-bridge vibration.