Study On Static Characteristics Of Large-scale Deep Water Steel Sheet Pile Cofferdam Structure

With the vigorous development of China’s highway and railway construction,more and more bridges need to cross rivers or the sea.The construction of the cross-sea bridge is closely related to the deep-water foundation of the bridge.The safety of the deep-water foundation determines the safety and stability of the upper structure of the bridge.At present,the deep water foundation of bridges in China is mainly composed of large group piles,and steel cofferdams are used as waterproof enclosures.Among them,steel sheet pile cofferdams have high construction speed,good waterproof effect,high strength,reusability,and no shape restrictions.Many advantages are popular in the construction of deep-water foundation cofferdams.On the basis of collecting and researching the research data of steel sheet pile cofferdam at home and abroad,this paper summarizes the calculation methods of internal force analysis of steel sheet pile cofferdam,including traditional calculation method and finite element method.In this paper,the R8# main pier steel sheet pile cofferdam project of Honghe Bridge is taken as the research background.The internal force check is carried out on the cofferdam structure by the equivalent beam method.It is preliminarily verified that the cofferdam is safe,and then modeled by ANSYS software.The life and death unit function realizes the overall analysis and construction stage analysis of the cofferdam structure,simulates the changes of support and load during the actual construction process of the steel sheet pile cofferdam,and analyzes the force during the four construction stages of the steel sheet pile cofferdam construction process.The maximum stress and displacement under four construction stages were obtained,which verified the safety and stability of the structure.Comparing the calculation results of the three analysis methods,the limitations of the traditional calculation method and the deficiencies of the overall analysis can be obtained.The analysis results show that the most unfavorable construction condition of the steel sheet pile cofferdam is not in the last construction stage.In order to ensure the construction safety of the steel sheet pile cofferdam,and better to modify the cofferdam structure during the construction process,the construction stage of the cofferdam structure is carried out.Analysis is very necessary.