Limbs, Variable Cross-section Hollow Thin-walled High Pier Continuous Rigid Frame Bridge To Bridge Phase Stability Analysis,

In recent years,more and more railway and road bridges adopt newer structures.Such as long-span,thin wall and hollow pier,super-high pier,etc.Those make the stability of bridges appears more pronounced than in the past.Especially in mountain areas,the height of those bridges are 100 metres,even 200 metres,then the importance of the stability is increased.The background to this dissertation is a limbs, hollow thin-walled and high-span continuous rigid frame bridge on the Xiarong Express Road.Using massive finite element analysis software-ANSYS(10.0),the liner and nonliner stability,the response of the bridge and the stability under seismic loads are detailedly studied.Also some parameters analysis. The main content of these studies are as follows:1.This paper summarizes the research course and present situation of hollow thin-walled and high-span continuous rigid frame bridge at home and abroad. It analyses and summarizes the existing achievement of bridge stability and does some overview of the basic theory of bridge stability.2. On the base of the former theory analysis, this dissertation uses two different elemet of ANSYS to simulate the bridge and calculate the liner and nonliner stability. Then the results are compared. We can come to some conclusions:Both stability coefficient of geometrical nonlinearity of the two element models are 31.6%-38.8% larger than their linear stability coefficient. In the model of beam element, the stability coefficient of geometrical nonlinearity is 31.7%-38.9% larger than it's dual nonlinear stability coefficient and In the model of shell element, the proportion is 13.4%-20.9%. These results show that:In the process of calculating the stability of this bridge, the geometrical and material nonlinearity should be fully considered.3.Transient analysis is done after selecting three different Seismic waves (El centro,Taft and Artificial seismic waves)and loading on three dimensions. These results show that:the responses of the bridge on the three different waves are similar. If the seismic waves loaded along the bridge and across the bridge are the same, the main direction of displacement is along the bridge. In other words, the stiffness along the bridge is less than across the bridge.4.Concerned several prominent factors(thickness of pier, thickness of diaphragm, concrete strength,location of diaphragm and temperature changes) of the hollow thin-walled high pier, the parameter analysis is done. We can get the order of stability coefficient with the variation of various parameters and this will Supply more theoretical basis for bridge design of this sort of bridge.