3D Bridge Modeling based on Parametric Design

Parameter design is an important means of the geometric modeling,three-dimensional visualization of the bridge is the development trend of today's bridge information technology.In order to satisfy the needs of visualization of the bridge appearance using parametric design method,the principles and methods of the geometry of parametric modeling are deeply discussed.Combining the characteristics of the bridge structure,geometric information and topological information of nine major bridge component structures(such as T beam,beam-column type pier,light abutment,etc.) are analyzed,the parametric design of bridge components is presented in details,the three-dimensional modeling of bridge components is realized;special primitives and components(such as arc inverted angle pier,abutment slope protection) rendering algorithm is studied.According to topological relations based on the spatial location of each component,bridge can be rapid spliced which uses parametric variables to drive calculation of the spatial position coordinates of each component.After completion of the bridge 3D parametric modeling drived by parameters,the user can visualize the design results.The 3D parametric bridge visualization system achieves fined model,thorough parametric,fast,clear classification,and good visual effects.