This tutorial was initially developed for bridge modeler in SAP2000, but the concept applies also to CSiBridge.

This tutorial describes the modeling process for a composite bridge composed of a concrete slab over steel girders with variable flange thickness.

Modeling steps

To obtain the variable flange thickness desired, users should assign non-prismatic girder sections to the bridge deck section.

Create new model from template

Define non-prismatic steel girder sections


Figure 1 - Section definition

Create bridge deck sections


Figure 2 - Bridge section data

Assign bridge deck sections to the bridge object


Figure 3 - Span assignments



Figure 4 - Extruded view

See Also