位移是反映结构性能和安全的重要指标。大型结构动态位移监测仍存在较多困难。摄像测量具有非接触、低成本等突出优点，有望成为一种实用方法，但其全天候工作性能评估及优化有待研究。开展了高层建筑动态位移全天候摄像测量长期室外试验，并以降雨天气下的位移实测数据为研究对象，分析了降雨对摄像测量精度的影响。降雨对摄像测量产生了显著影响，导致位移测量精度明显降低。为拓宽摄像测量的适用环境，提出了采用自适应滤波方法进行降噪处理。结果表明，自适应滤波方法能有效地去除测量噪声，提高摄像测量在暴雨环境下的测量精度，为实现高层建筑动态位移全天候摄像测量提供了必要条件。%Displacement is a good index for structural behavior and safety status.However,measuring displacement of structures under dynamic excitations is still a challenging task.Videogrammetry has a great potential for dynamic displacement measurement due to its non-contact and low-cost characteristics.Nevertheless,its all-weather working performance should be fully evaluated and optimized before its wide applications.Here,long-term outdoor dynamic displacement monitoring tests using videogrammetry were conducted.A virtual displacement generation device was fabricated to generate dynamic displacements of various structures and an industrial digital camera was employed to monitor virtual displacements.Here,virtual displacements of high-rise buildings measured under raining conditions were analyzed.It was shown that raining has significant effects on videogrammetry,it obviously reduces the accuracy of displacement measurement data.To widen the applicability of videogrammetry,the adaptive filtering method was proposed to de-noise the displacement measurement data.The results showed that the adaptive filtering is well capable of decreasing or removing measurement noises and improving the accuracy of displacement measurement data;it is helpful for the realization of all-weather videogrammetry for dynamic displacement monitoring of high-rise buildings.
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