Research On Cable Modeling And Layout Of Railway Signal System For BIM

The railway signal system is essentially a weak electric cable system.The cables/wires in the signal system has a complex spatial topological relationship with the building components and functional spaces designed by other trades.So the design of railway signal system,traditionally presented with 2D drawings,should follow the BIM 3D modeling principles.However,the prevailing design patterns for modeling signal cables have limitations.The “2D-to-3D” pattern results in heavy workload to designers and is prone to errors and omissions,while the “3D-to-2D” design pattern has many conflicts with existing design workflow.This research propose a new design pattern that the initial 2D logic model drives the 3D physical model and then 3D information in the physics model feedbacks into the 2D logic model.In this way,the signal engineer can prevent from suffering from changing their work procedure and design pattern,and meanwhile the computer can assist in automatic generation of 3D cable model,and further the representation of 2D logic models.In order to reach the aforementioned goals,the study accordingly develops automatic generation algorithms for both the cable routing points and the 3D shape of cable segments.In addition,a linkage template is specifically designed for feed backing key 3D information of cable routing points into the logic model.Furthermore,a software prototype used for 3D cable generation has been developed on the Rhino Grasshopper platform.Finally,a real case of the cable design of the Zhangjiazhuang railway station is studied to verify the effectiveness and practicability of the proposed method.