The Study On Pier Stiffness Match Of Continuous Rigid Frame Bridge With High-pier And Multi-span

Increase with the span continuous rigid frame bridge,span increases,long increased the height of the pier,and statically increased the number the height of large with different,the stress of the beam and the pier is asymmetry.Especially due to prestress,continue shrinkage and creep,temperature load,based uneven settlement will be on the whole structure brought large secondary internal force.Continous rigid frame bridge pier and beam consolidation,when determining the parameters of the upper structure, pier stiffness have great influence on structural internal force distribution and deformation, reasonably high pier matching to ensure structure to meet the norms, at the same time, stress is more reasonable.In this paper,taking Xianyang to Xunyi highway section of Sanshui River Bridge as engineering background,First of all, the use of finite element program of different anti push stiffness and high pier structure model were analyzed, through the comparative analysis to find out the key factors of affect the structure of the internal force and deformation;Then, two simple object functions are builded based on the results of paremeter differential, the use of network search comparison method, the high pier matching degree were analyzed, and pier stiffness matching optimization design provides useful conclusions.The basic conclusion are as follows:1、Summed up in recent years of high pier is matched with research related to the basic calculation method and the results of the theory, analyze and summarize the pier stiffness of continuous rigid frame bridge internal force and deformation.2、Analysised the high pier structure type commonly used summary and comparison analysis and the different structure types and high pier established anti push rigidity computation model, summarizes the different types of piers and stress stage, high pier anti push rigidity calculation method, the scope of comparison of different pier and comparative analysis of high pier anti push rigidity influence factors.3、On the pier at different bit super high pier stiffness change, in the load and the structure internal force and the pier top displacement variation of comparative analysis, this paper concludes that the distance across China and Vietnam far the pier stiffness change on structural internal force produced.4、Comparison of different load conditions, pier stiffness change, continuous influence of internal force and displacement of the rigid frame bridge sensitivity, through comparative analysis it is concluded that the constant load of continuous rigid frame bridge with high pier stiffness matching impact sensitivity smaller; changes in temperature of the system and concrete shrinkage and creep on the influence of internal force and deformation.5、Under the control target of the main pier’s stress and internal force,pier height equal to the number of different cross-rigidity continuous rigid frame piers match analysis and study,analyze different stiffness match,the pier top,internal force and stress variation at the end of the pier,through the analysis results:For symmetric even-span continuous rigid frame bridge,pier stiffness can be matched with the rest of the pier stiffness in any ratio;odd-span continuous rigid frame bridge,to ensure the structural strength and stability at the same time,near the edge of the adjacent side of the pier pier and across the side near the mid-span pier stiffness ratio of about 1:6~1:7 for the benefit,and with span ratio is different between different reasonable stiffness ratio pier;pier height when the sides reached 0.5,pier stiffness ratio between reasonable in about 1:4,the side pier set rigidity smaller twin piers more beneficial to the force structure.