Research And Development Of Highway 3D Visibility Analysis Model In BIM Environment

The application of BIM technology in the highway engineering industry has promoted the transformation of highway route design from two-dimensional(2D)independent design to three-dimensional(3D)information-aided design,which has promoted the transition of design evaluation indicators and means to a 3D environment.Visual information is the basic information for the driver to drive safely and is also the basic basis for highway landscape evaluation.Research on highway visibility analysis model in BIM environment is the key to solve the problem of 3D visual information acquisition.In this paper,a 3D visibility analysis model of highway in BIM environment is established,including line of sight analysis model and field of view analysis model.Based on the improved MT algorithm,the core problem of the intersection of the line of sight and surface is solved.A fixed-step scanning algorithm and an arbitrary point A+R dual-mode visibility analysis algorithm are proposed,and a line of sight analysis model is established.A viewsheds analysis algorithm based on TIN triangle element and a landscape area importance evaluation algorithm based on projected area correction are proposed,and a viewsheds analysis model is established.Based on AutoCAD Civil 3D and C# language,a highway 3D visibility analysis system including highway 3D line of sight inspection module,arbitrary point visibility analysis module,viewsheds analysis module,and landscape area importance evaluation module was designed and implemented.The typical highway section and representative software are selected to compare the reliability and practicability of the system analysis results,and the scientificity of the algorithm is verified.The 3D visibility analysis model of the highway established by the thesis provides information such as 3D line of sight,visibility and viewsheds at any point on the highway,and provides sufficient visual information support for the highway route design process.Among them,the highway line of sight analysis model can be used for sight distance analysis,safety design and evaluation,while the viewsheds analysis model is used for highway landscape importance analysis and landscape design,which plays an important role in improving the support level of highway BIM software for the design process and decision-making.