Research On Precision Detection Of Fabricated Concrete Components Based On BIM And 3D Laser Scanning

With the rapid development of prefabricated buildings,the quality problems of precast concrete components are becoming increasingly prominent.The uneven design level of components,different production levels,improper installation and operation specifications and weak supervision system still have great room to improve the construction accuracy and detail control level of the project.With the development of building digitization,the application scope of BIM(Building Information Modeling)technology is expanding,but relying only on BIM technology is easy to ignore the changeable conditions of the construction site,resulting in great differences between the prefabricated building construction site and the BIM design model.Under the comprehensive development and application of "BIM+" technology,combining BIM with 3D laser scanning technology to compare and analyze the forward design model and reverse 3D scanning model can realize the high-precision monitoring and detection of the production and installation of prefabricated concrete components and improve the detail control.However,at the current stage,the application of BIM and 3D laser scanning technology to prefabricated concrete components lacks a complete set of error control process,the specific application objectives of each step are not clearly explained,and the data acquisition lags behind,which affects the high-precision data output as a whole.Therefore,by analyzing the feasibility of applying BIM and 3D laser scanning technology to prefabricated concrete buildings,combining with the production and installation error sources of prefabricated concrete components,this paper puts forward the application scheme of BIM and 3D laser scanning in the accuracy detection of prefabricated concrete components,and explains the specific application objectives and control points.Finally,the feasibility and data effect of the scheme are verified through case analysis,which has a certain reference significance for the subsequent research.The main research work is as follows:(1)The production and installation accuracy of BIM and 3D laser scanning prefabricated components are analyzed.Based on the principle of BIM and 3D laser scanning technology,the technical implementation path of their application in prefabricated buildings is determined.Combining with the error sources of prefabricated concrete components,the standards in the current specifications are analyzed,and the error result law is analyzed by using the tolerance theory to determine the feasibility of applying the integrated technology to the accuracy detection of prefabricated components.(2)In order to improve the accuracy of 3D laser scanning and BIM technology in the application of prefabricated concrete components,the specific scheme of each step of technology implementation is formulated,including four stages: 3D laser scanning scheme,data acquisition principle and process,point cloud processing accuracy control,BIM model accuracy control,model comparison accuracy control.Refine the application objectives of each stage,and determine the implementation methods,principles,personnel and hardware configuration.This paper focuses on the detailed research on the layout principle of 3D laser scanning station,on-site scanning method,high-precision data acquisition and processing,BIM model control and so on.(3)Taking a prefabricated project 5# building in Beijing as an example,the specific application effect and data accuracy of each step are displayed through case study,the case application of BIM and 3D laser scanning technology is comprehensively evaluated,the implementation scheme process proposed in this paper is verified,and a reference is provided for further research.