The Optimization Design And Stress Analysis Of Mechanical Properties For Continuous Rigid Frame Of Large Elevation Difference Bridge Pier

Actually the large elevation difference of rigid frame bridge piers is high and low piers,The High pier stiffness has two piers,at the same time by the upper structure load,the two piers is not performing the same characteristics of the force and deformation,the more stiffer of the bridge pier the more stress it will withstand in theory.To analyse how much of the piers difference both of the piers characteristic will perform very well,the finite element software is used to analysis the performance of the different height of the bridge of the symmetry span,and analysis the result of how much of the different height both of the bridge piers will performance very well.According to the theory,some improvement schemes are been put forward,and the solutions are verified,some suggestions about the design and construction are put forward after analysis the feasibility of the schemes.The finite element software is used for carring on the calculation and analysis of the high pier continuous rigid frame bridge,the research contents are put forward as follows:(1)Through the finite element software of main girder span is symmetrical,the stress of the upper structure and the structure remains the same,piers using rectangular double-thin wall piers of the section,some of analysis are been done,such as analysing one side by changing the other side of height of the bridge pier,then compare and analysis of the different height of pier characteristics of force and deformation.(2)After analysing of(1)results,some improvement solutions are been put forward,and analysing whether the schemes are feasible.(3)Making a summary analysis of the results based on(1)and(2)and put forward some opinions and Suggestions of the continuous rigid frame of high pier bridge design and construction.According to the analysis result:(1) with the gradual increase of the pier, that is, the relative difference between the two sides of the pier is more and more big, the temperature of zero gradually moved to the larger side of the bridge pier. For the double thin-wall pier, when the pier in 30-40 m center temperature will be between stiffness larger short pier pier of double limb, this will cause the double limb pier at the top of the main beam by a greater role in the tension, for full prestressed concrete need attention.(2) when the pier difference is less than 30 m, high pier and low pier can be used in the same size section, at this time, the force of the high and low piers is not very large.(3) when the height of pier pier difference is greater than 40 m when to change the high pier of the relative stiffness can increase the thickness of piers, such as theuse of tapered pier, also need in double thin-wall pier between the set of coupling beams, so as to increase the overall stability of the high pier.(4) when the pier difference greater than 30 m can also use rigid contact beam bridges to solve the stress problem of the bridge of the big difference in asymmetry.