The Stability Of Large-span Steel Truss Arch Bridge And Ultimate Bearing Capacity

Steel truss arch bridge is a structural style which is often used in long-span bridge project, and its prominent stability is always one of the most important factors in controling the bridge design. This paper analyses the stability and the ultimate load-carrying capacity of the Xinjiaomen bridge, which is with a 436m central span length, using the universal FEM program, reach some conclusions. The main work are:1. Through the analysis of elasticity buckling on the Xinjiaomen bridge, know the local bucking of the arch rib is the main bucking modals of the long-span steel truss arch bridge, and compared the influences of the wind load and the live load to the elasticity stability.2. By the analysis on the ultimate load-carrying capacity of the Xinjiaomen bridge, study its lapse path tracked and its lapse mechanism, reveal the essential of the lapsing of this kind bridge and its weakness.3. Through the analysis on the influence of material nonlinear and geometric nonlinear to the ultimate load-carrying capacity of the Xinjiaomen bridge, point out that in the analysis of the ultimate load-carrying capacity of the steel truss arch bridge, the influence of geometric nonlinear is little,while material nonlinear plays a decisive part..4. By calculating the ultimate load-carrying capacity of the bridge at the case of different load distributions and different original defect, study the influence of load distributions and original defect to the ultimate load-carrying capacity of the same kind of bridge.5. By calculating the ultimate load-carrying capacity of the bridge loaded by horizontal wind load and live load, know the influence of horizontal wind load to the ultimate load-carrying capacity of the bridge.