基于动态测量柔度矩阵的悬索桥吊索损伤检测

Cable damage detection of a suspension bridge in terms of dynamically measured flexibility matrix

基于动态测量柔度矩阵的结构形变和变形曲率是一种有效的悬索桥吊索损伤检测指标。通过模拟仿真不同损伤程度和不同噪声影响下的8种吊索损伤情况,讨论了方法的可行性。仿真结果表明,动态测量柔度法能够定位5%噪声水平下的损伤程度达到90%及以上的单个和多个损伤。通过实验室模型测试来进一步验证这些损伤指标对检测和定位损伤的有效性,并在实验中分析了模态截断对损伤估计的影响。实验表明,与变形位移相比,变形曲率对于检测和定位吊索损伤更为有效。

The deformation and deformation curvature obtained by measuring the flexibility matrix are effective means to detect the damaged cables of suspension bridges.A simulation method,named as dynamically measured flexibility method,was proposed to locate damages in 8 scenarios at different locations of cables with different damage intensities and noises.The result shows the presented method is able to locate the single/multiple damages with severity of 95% and with the noise level of 5%.Then,laboratory mock-up tests were carried out to verify the effectiveness of the flexibility metrices for detecting and locating damages.The experimental results show that deformation curvature is more effective for detecting and locating damages than flexibility-based displacement patterns.In addition,modal truncation is to be minimized since measured flexibility has to approximate actual flexibility.