Suspension bridges - Computational Analysis and Design of Bridge Structures - page 394

Figure 12.17 3D FEA model of Bay Bridge by VBDS.

load analysis and the final state for live load analysis. The model is built
in 3D using VBDS program (Wang and Fu 2005) and cross-checked using
SAP2000 (2007). The main cable and hangers are modeled as truss ele-
ments; all others are modeled as beam elements, including members of the
truss stiffened girder. For simplicity, deck stringers are not modeled, but its
weight plus all other superimposed dead loads are included. All members
of each truss floor beam are also modeled as beam elements (Figure 12.17).
The entire model contains 5264 elements and 2798 nodes.
The saddle is not indicated as rigidly connected to the pylon when the
bridge is in services. So the modeling of the saddle and its connections are
simplified as shown in Figure 12.16(b).
In addition to dead loads, live loads in the main span and far side span
for extreme bending moment at the bottom of tower leg and loads due to
temperature change are analyzed. As shown in Figures 12.18 and 12.19,
the extreme bending moment due to live loads is −8456 kN-m, and its
corresponding deflection in the middle of the center span is 1372 mm.
Table 12.2 lists other results of the static analyses.

−8456 2395

Figure 12.18 Extreme live load bending moment (kN-m) in one pylon leg of Bay Bridge.