基于实际影响线的桥梁快速检测方法

Bridge Rapid Detection Method Based on Actual Influence Lines

针对桥梁静载试验存在费时费力、长时间影响或中断交通的缺点,提出一种基于实际影响线的桥梁快速检测方法。首先对桥梁进行标定试验,从单一车辆过桥的动力响应中提取桥梁实际影响线;引入车辆轮胎-路面接触力分布模型,可重构出静载试验不同加载工况下桥梁相应测点的静力响应,从而实现快速检测。以某六跨连续梁桥为背景,针对其第1跨分别进行单一车辆快速检测与多车辆静载试验,对比主梁跨中挠度和应变响应。结果表明:主梁跨中挠度和应变的快速检测结果与静载试验结果吻合较好,最大偏差为7.6%,基于实际影响线的快速检测方法具有较高精度。

We propose a rapid detection method for bridge structure based on actual influence lines,which overcomes the drawbacks of time-consuming,being labor-intensive,long-term impact or interruption traffic that exist in bridge static load tests.Firstly,an actual influence line is extracted from bridge dynamic responses based on a calibration test with a passing vehicle.Then,a tire-pavement contact force distribution model is introduced to reconstruct bridge static responses under different loading conditions,so that the rapid detection can be realized.Taking a six-span continuous girder bridge as an example,we performed the one-vehicle based rapid detection and the multi-vehicle based static load test at the first span,and compared the mid-span deflection and strain of main girder.The results show that the rapid detection values of mid-span deflection and strain of main girder agree well with those by static load test,and the maximum deviation is 7.6%,indicating that the rapid detection method based on actual influence lines possesses a high precision.