3D laser scanning can serve the geometric deformation detection of steel structures. However, the process of handling large-scale point clouds remains labor-intensive and time-consuming. This paper presents an automated approach to extracting the precise axes from point clouds and updating the associated BIM model for steel structures. The strategy involves the initial geometry extraction from IFC files and instance segmentation through the reference point cloud simplification and index rules. Then the axes of all components with different sections are detected through the corresponding standard sections and genetic algorithm. Lastly, the geometric information for each component in the BIM is updated by modifying the IFC file. The method is implemented on a steel framing comprising 218 components, indicating that the workflow works effectively with noise and occlusion. The difference in average distances from 218 components to the scanned point cloud is reduced from 17.50 mm before updating to 4.00 mm after updating.

中文翻译：

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扫描与 BIM：通过激光扫描自动进行几何检测和钢框架的 BIM 更新


三维激光扫描可用于钢结构的几何变形检测。但是，处理大规模点云的过程仍然需要大量人力且耗时。本文提出了一种从点云中提取精确轴并更新钢结构相关 BIM 模型的自动化方法。该策略涉及从 IFC 文件中提取初始几何图形，并通过参考点云简化和索引规则进行实例分割。然后通过相应的标准截面和遗传算法检测所有不同截面的组分的轴线。最后，通过修改 IFC 文件来更新 BIM 中每个组件的几何信息。该方法在由 218 个组件组成的钢框架上实施，表明该工作流可以有效地处理噪声和遮挡。从 218 个组件到扫描点云的平均距离差异从更新前的 17.50 mm 减小到更新后的 4.00 mm。