Engineers can today capture high-resolution video recordings of bridge movements during routine visual inspections using modern smartphones and compile a historical archive over time. However, the recordings are likely to be from cameras of different makes, placed at varying positions. Previous studies have not explored whether such recordings can support monitoring of bridge condition. This is the focus of this study. It evaluates the feasibility of an imaging approach for condition assessment that is independent of the camera positions used for individual recordings. The proposed approach relies on the premise that spatial relationships between multiple structural features remain the same even when images of the structure are taken from different angles or camera positions. It employs coordinate transformation techniques, which use the identified features, to compute structural displacements from images. The proposed approach is applied to a laboratory beam, subject to static loading under various damage scenarios and recorded using multiple cameras in a range of positions. Results show that the response computed from the recordings are accurate, with 5% discrepancy in computed displacements relative to the mean. The approach is also demonstrated on a full-scale pedestrian suspension bridge. Vertical bridge movements, induced by forced excitations, are collected with two smartphones and an action camera. Analysis of the images shows that the measurement discrepancy in computed displacements is 6%.

如今，工程师可以使用现代智能手机在例行视觉检查期间捕获桥梁运动的高分辨率视频记录，并随时间汇编历史档案。但是，录音可能来自不同品牌的相机，放置在不同的位置。以前的研究还没有探索这种记录是否可以支持对桥梁状况的监视。这是本研究的重点。它评估了用于状态评估的成像方法的可行性，该方法独立于用于单个记录的摄像机位置。所提出的方法依赖于这样的前提，即即使从不同角度或相机位置拍摄结构的图像，多个结构特征之间的空间关系也保持相同。它采用坐标变换技术，它们使用识别出的特征来计算图像的结构位移。所提出的方法应用于实验室光束，在各种损坏情况下承受静态载荷，并使用多个摄像机在一定范围内记录下来。结果表明，从记录中计算出的响应是准确的，相对于平均值，计算出的位移相差5％。该方法还在全尺寸的行人悬索桥上得到了证明。由两台智能手机和一个运动相机收集由强制激励引起的垂直桥梁运动。图像分析表明，计算位移的测量差异为6％。在各种损坏情况下承受静态载荷，并使用多个摄像机在一定范围内进行记录。结果表明，从记录中计算出的响应是准确的，相对于平均值，计算出的位移相差5％。该方法还在全尺寸的行人悬索桥上得到了证明。由两台智能手机和一个运动相机收集由强制激励引起的垂直桥梁运动。图像分析表明，计算位移的测量差异为6％。在各种损坏情况下承受静态载荷，并使用多个摄像机在一定范围内进行记录。结果表明，从记录中计算出的响应是准确的，相对于平均值，计算出的位移相差5％。该方法还在全尺寸的行人悬索桥上得到了证明。由两台智能手机和一个运动相机收集由强制激励引起的垂直桥梁运动。图像分析表明，计算位移的测量差异为6％。由两个智能手机和一个运动相机收集了由强制激励引起的感应。图像分析表明，计算位移的测量差异为6％。由两个智能手机和一个运动相机收集由强制激励引起的感应。图像分析表明，计算位移的测量差异为6％。