Many existing structures suffer from damage due to age or accumulated damage from hazards. It is important to accurately assess the present conditions of these aging, deteriorating, and damaged structures. In recent years, laser scanners have been increasingly used for capturing the in situ conditions of structures. They are used for collecting dense and high‐resolution point clouds of scenes for structural engineering applications. However, automatically extracting meaningful information from the point clouds remains a challenge, and the current state‐of‐the‐art requires significant user interaction. In this work, a process for automatically extracting information from laser datasets such as the location, orientation, and size of objects in a scanned region, and location of damaged regions on a structure is established. First, widely accepted point cloud processing steps are used to divide the collected laser scanner data into meaningful point clusters. A new graph‐based object detection algorithm is then used to generate skeletons of the extracted point clusters in order to detect structural members by using a model library consisting of common structural shapes. The obtained member information is then used for developing a new graph‐based damage detection method, which compares the fitted object model with the as‐is point cloud of the investigated object for locating defects, detecting alignment issues and points of discontinuity, computing changes in the cross‐section through area calculation, and determining the total volume change on the investigated member. The effectiveness of the developed graph‐based object and damage detection algorithms are tested and validated on test specimens and test‐bed bridges.

中文翻译：

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使用提取的构件属性进行基于激光的表面损伤检测和量化

许多现有的结构由于老化而遭受损坏，或者由于危害而累积损坏。准确评估这些老化，恶化和损坏的结构的当前状态非常重要。近年来，激光扫描仪已越来越多地用于捕获结构的原位条件。它们用于收集密集且高分辨率的场景点云，以用于结构工程应用。但是，从点云中自动提取有意义的信息仍然是一个挑战，并且当前的最新技术要求大量的用户交互。在这项工作中，建立了一种自动从激光数据集中提取信息的过程，例如扫描区域中对象的位置，方向和大小以及结构上受损区域的位置。第一，广泛接受的点云处理步骤用于将收集的激光扫描仪数据划分为有意义的点簇。然后使用一种新的基于图形的对象检测算法来生成提取的点簇的骨架，以便通过使用由常见结构形状组成的模型库来检测结构成员。然后，将获得的成员信息用于开发基于图的新损伤检测方法，该方法将拟合的对象模型与被调查对象的原样点云进行比较，以查找缺陷，检测对齐问题和不连续点，并计算变化。通过面积计算来确定横截面，并确定被调查构件的总体积变化。