Application Research On Accurate Modeling Of Rail Transit Line Based On BIM Technology

With the rapid enhancement of China’s comprehensive national strength,the state has invested a lot of funds in infrastructure,and the rail transit industry has ushered in a new round of construction climax.track engineering is a comprehensive project that includes a number of specialties.In the entire life cycle management of project design,construction,operation and maintenance,the issues of collaboration and information interaction among various specialties have always plagued practitioners.Building Information Modeling(BIM),as a three-dimensional information integration technology applied to engineering design and construction management,can effectively solve the problems existing in the traditional management mode of rail transportation professionals.The core of BIM technology is the creation,modification,and invocation of model information.As a carrier of all information,accurate models are the basis for the application of BIM technology.Therefore,it is of great significance to study the accurate modeling methods of rail transit engineering lines.This article mainly researches the accurate modeling method of rail transit lines based on BIM technology from two aspects of track components and terrain.The main research contents and results are as follows:1.The geographical environment along the rail transportation project is complex,and the traditional terrain surveying method has great limitations.The terrain modeling method proposed in this paper is a combination of tilt photography technology and 3D point cloud processing technology.The ground photos are automatically matched for aerial triangulation,which improves the matching accuracy of the control point coordinate data.At the same time,the point cloud data generated by dense matching is edited to generate a TIN grid and contour model,thereby establishing a terrain model of the area.Experiments show that this method has the characteristics of fast and efficient,low cost and high precision.2.Traditional geometric modeling technology has a large workload and low data reusability,which greatly limits the application and development of BIM technology in actual engineering.Based on the characteristics of track engineering,this paper uses parametric modeling theory to perform constraint analysis and dynamic parameter setting on track components,and establishes a track standard component library.Engineering applications prove that this method effectively improves the modeling efficiency of track components.3 According to the characteristics of different track structures,this article uses Dynamo visual programming tool to develop Revit secondly,call the corresponding components in the standard component library to automatically assemble on the terrain model,and obtain the 3D model of the track line that conforms to the internal logical relationship and spatial constraint information.