Research On High Pier Construction Technology Of Long Span Continuous Rigid Frame Bridge In Severe Cold Region

Expressway is an important guiding infrastructure to guarantee economic and social development.With the development of Chinese economy,the national demand and investment for highway traffic infrastructure construction is also increasing.Bridge construction is developing towards the mountainous area with complex terrain,and the height and number of bridge piers are constantly breaking records.High pier with large slenderness ratio,smaller push stiffness,but because of the high pier uneven uneven,verticality deviation in the process of construction and high pier pier top displacement under the action of sunshine,is the high pier deformation continues to increase,in turn,the main cause of instability,cracks and other damages,for the safety of bridge structure and life cycle constitutes the great threat,so the design and construction of the high piers should be specially considered.Liangshui super large bridge is the landmark project of huinan to baishan expressway.The main bridge is(86+160+86)m prestressed concrete continuous rigid frame,and the main bridge pier is 94.0 meters high.Different from other regions,construction in severe cold areas in northeast China is limited by temperature.There is about 6 months overwintering period in each construction year,and there is little research literature on the stability and strength of high piers under the condition of long time and large cantilever.Therefore,this article relying on Liangshui super large bridge design,combining with the characteristics of cold region,through analyzing the adaptability of different high pier structure,summarizes the influence factors of high pier structure,cross section selection,through calculation and analysis of double limb hollow thin-walled pier,the design key points of high piers,and connecting with the construction technology of optimization design.To sum up,this paper mainly does the following work:(1)on the basis of consulting a large number of design and construction data of high piers at home and abroad,the main influencing factors of design and construction of high piers in severe cold areas and the selection of relevant design parameters were proposed.(2)according to the construction status of the severe cold area,two control states are proposed for the stability calculation of the high pier,namely,the maximum cantilever state and overwintering cantilever state,to clarify the difference of the two calculation parameters,and ANSYS11.0 is adopted to calculate and analyze the stability of the first class and the stability of the second class respectively.(3)the structural forms and adaptability of different piers were discussed,and the control section was checked during construction and use of high piers in severe cold area.The strength and crack of the control section were checked by finite element software.(4)the construction technology of different bridge piers is discussed,and the cantilever formwork construction technology suitable for severe cold areas is proposed.(5)the design of high piers should be combined with the actual construction to ensure that the design should be extended to the whole process of engineering construction,and the optimization design in the construction process of high piers should be proposed.