Abstract: | 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. |