Cable-stayed bridges are structural systems effectively composing cables, main girders and towers. This bridge form has a beautiful appearance and easily fits in with the surrounding environment due to the fact that various structural systems can be created by changing the tower shapes and cable arrangements.
Cable-stayed bridges are structures that require a high degree of technology for both design and construction, and hence demand sophisticated structural analysis and design techniques when compared with other types of conventional bridges.
In addition to static analysis for dead and live loads, a dynamic analysis must also be performed to determine Eigen values. Also moving load, earthquake load and wind load analyses are essentially required for desi ning a cable-stayed bridge.
To determine the cable prestress forces that are introduced at the time of cable installation, the initial equilibrium state for dead load at the final stage must be determined first. Then, construction stage analysis according to the construction sequence is performed.
This tutorial explains techniques for modeling a cable-stayed bridge, calculating initial cable prestress forces, performing construction stage analysis and reviewing the output data. The model used in this tutorial is a three span continuous cable-stayed bridge composed of a 220 m center span and 100 m side spans. Fig. 1 below shows the bridge layout