Stability Analysis ofPrelim inary Schemes of Nanjing No. 3 Bridge in Construction Stage

Three preliminary schemes of theNanjingNo. 3 bridgewere investigate by considering the nonlinearity of structures and the ultimate load-carrying capacity of components. They are the schemes of steel cable-stayed bridgewith one tower and two poles, orwith two towers and one pole, orwith two towers and two poles. And in the investigation, the superposition effects of deformations and stresses during the construction were also included. The research was focused on the stability of structures during the construction. The research resultshows thatelastic stability factors for the three schemes are 4. 9 to10. 2, and theirnonlinear stability factors are 2. 1 to7. 9, so theirelastic stability and nonlinear stability are adequate in construction stage. At las,t their stability safety factors in a state of ultimate load-carrying capacity during constructionwere appraised.