Research On The Integration Of Railway BIM Based On WebGl

In the application of building information modeling(BIM),a large-scale and large-scale 3D model needs to be displayed.When these three-dimensional models are displayed on a professional graphics workstation,they often experience problems such as stuttering and flickering due to insufficient computer memory.Moreover,the environment in which BIM applications can be used on railway construction sites is poor,and it is difficult to equip users with professional equipment.This requires the graphic display device to be able to smoothly support the display of large 3D models on devices with smaller configurations and even on mobile devices.To meet the special requirements of BIM field applications.The BIM model is a large platform model that integrates big data.The final expression is a visual multi-dimensional,multi-application scenario,multi-functional computer graphics model.In large railway BIM models,there are usually many components with different locations but the same geometry.The 3D analysis engine analyzes model files in units of components.During analysis,differences in geometric shapes and semantic information between them cannot be identified.Will cause problems such as repeated data analysis,model data is too large,model semantics and geometric data redundancy and other issues.In addition to viewing the three-dimensional model,BIM should also include the interaction of additional information on the model,so that the transmission of information can form a unified whole from top to bottom.This requires a unified information integration platform to import model information into an online space,so that all parties in the project can interact based on this model.In view of the current existing technology,it is very inconvenient to upload the original BIM model directly,both upstream and downstream.Based on the current development trend of railway information technology in the computer field,this paper studies the lightweight method of railway model and the three-terminal collaboration and data integration method of railway BIM model based on BIM and WebGL technology release of relevant standards.It provides a new method and new idea for the railway project information management.The main research contents and research results of the paper are as follows:(1)By analyzing the complete railway model data,analyzing the three-dimensional data of the model saved by the fastener model,using Revit modeling software to establish fastener models with different LOD levels of accuracy,and reducing the track board through the model reuse method during the track board modeling stage The file size of linear structures is reduced,Lightweight the basic component model of railway engineering Generate LOD model library.(2)According to the different stages of the BIM model,select family libraries with different LOD model accuracy for batch assembly,and use the Revit family instance placement method to determine the instance position and instance deflection angle through Revit secondary development,so that the family instances are accurately placed on a straight line.,Curve,and the corresponding position of the transition curve.(3)Study the model display method of the railway engineering model on a browser that supports WebGL,by converting the file format of the original model to a JSON data format that supports browser parsing.It can be displayed on the web browser page,and the docking and integration of external multi-source data is performed through index numbers such as the unique index ID of the model.Finally,a complete railway engineering information management platform is built.(4)Research the mobile BIM 3D engine that can be applied across platforms.On-site management of BIM models and data reading and writing are implemented by encapsulating file addresses as two-dimensional codes.Investigate the data integration method on the mobile terminal,so that the mobile terminal on the field can interact with the server data,thereby reducing the occurrence of data disconnection.