基于三维激光扫描的大跨度网架结构BIM模型矫正研究

Research on correction of BIM modelof the large span grid structure based on 3D laser scanning

为了构建反映真实工程信息的BIM模型,本文提出采用三维激光扫描并矫正大跨度网架结构BIM模型的方法。首先基于三维激光扫描技术扫描大跨度网架结构,得到多个基站的点云数据;针对配准后的大跨度网架结构工程点云,提出通过点云分块、切片、圆搜索、圆心聚类、球搜索实现大跨度网架结构的焊接球搜索的方法;通过拟合焊接球点云得到焊接球的空间坐标,进一步矫正BIM数字模型中焊接球的位置,实现大跨度网架结构BIM更新。为了验证本方法的准确性,将该方法用于海口某码头网架结构的数字孪生模型构建,从1118个焊接球中准确识别出了96.5%的焊接球,焊接球的直径拟合最大误差小于7mm,并通过焊接球的坐标矫正了大跨度网架结构BIM模型,其中焊接球矫正位移约0.1m,该方法实现了真实网架结构的BIM模型构建。

To establish a realistic BIM model of the large-span grid structure,a method of correcting BIM model with the 3D laser scanning wasproposed.Firstly,based on the 3D laser scanning technology,the large-span grid structure was scanned with the optimal position layout of the station.Then,the method for searching welded sphere joints was proposed,which including point cloud segmentation,slicing,circle search,circle center clustering,and sphere searching.The coordinates of the welding ball in the BIM model are corrected by the welded sphere joints searched in previous step.A large-span grid structure in Haikou,was used to validate this method,and about 96.5%of the welded sphere joints were accurately identified,and the diameter fitting error of the welded sphere was less than 7mm.Then the BIM model was corrected by the coordinates of the welded sphere joints.During this process,the maximum coordinate shift of the welded sphere joints was close to 0.1m.The realistic BIM modelof the large-span grid structure was established successfully.