Research On Integrated Modeling Method Of Line Structure Based On BIM

As a national key infrastructure construction project,railway project has a long investment cycle and high technical requirements.Especially with the development of economic technology and the continuous improvement of travel quality demand,higher standards are put forward for railway design,construction,operation and other links.With the development of information technology,railway route selection design has gradually entered the stage of digital route selection.Especially with the development of BIM technology,the design concept has gradually changed from "hand in drawings" to "hand in models".However,the existing BIM design of railway mainly concentrates on individual buildings such as bridges,tunnels and stations.There are few studies on the overall design of railway line structure,the unified standard model component library is not perfect,and the integration algorithm between different parts of the structure is not mature enough.Therefore,this paper takes Civil3 D as the modeling and development platform,studies the parametric BIM models and assembly methods for different types of line structures,and implements the design of integration algorithm with three-dimensional terrain to realize the three-dimensional expression of the design scheme.At the same time,combined with multi-body dynamics theory and UM vehicle model,the main dynamic indicators of each section are displayed in real time in three-dimensional scene as a reference for operation evaluation.The main research contents are as follows:(1)Using Civil3D platform,the method of creating three-dimensional digital terrain model using various types of terrain data is studied.The related parameters of line design based on three-dimensional terrain such as elevation,gradient and slope direction are analyzed.Line position expression and vertical section design are completed by using the built terrain model.(2)Based on the BIM requirement of track design,parameterized module of track cross-section design and parameterized module of track structure are constructed respectively.The module of cross-section design can realize automatic matching of cross-section type with mileage and terrain,and seamlessly integrate with terrain model by interactive calculation.(3)Tunnel components are created by using the component editor Subassembly Composer and interacted with the terrain model to create the tunnel parametric model.The model can be modified by modifying the parameters.A parametric frame bridge and culvert model is built based on the function of Revit family library.Subgrade,bridge,tunnel and track models are integrated and connected by dynamic introduction method to realize BIM expression of line.(4)In order to accurately judge the dynamic characteristics of the line,the corresponding vehicle model is constructed by UM software,the design line conditions are introduced,the track dynamic indexes are calculated,and the corresponding mileage and real-time display are realized in the process of three-dimensional roaming,which is an effective supplement to evaluate the level of the line design.