Research on Stress-strain Analysis and Thickness Design Method of Steel Casing for Cofferdam Bottom Sealing Concrete
Bridges are important infrastructure for national economic construction and social development.Improving the interfacial bonding force between the bottom concrete and the steel casing is crucial for the stress of the cofferdam in the bridge foundation.The circumferential deformation and expansion at the interface of the steel casing cause the concrete to be in a locally compressed state,which plays a decisive role in the bonding force between the two interfaces.At present,there is no complete and clear calculation method for the thickness design of steel casing,and relying solely on the standard thickness value is too conservative.Based on the generalized Hooke's law of elasticity and the symmetry of stress-strain relationship in axisymmetric systems,a mathematical model of strain field for axisymmetric thin-walled steel casing under axial load is established.By constructing the equilibrium differential equation,geometric equation,and constitutive equation of the microelement,the circumferential strain and displacement relationship of the thin-walled steel casing under axial load is analyzed,and a design method for the thickness parameter of the cofferdam bottom sealing concrete steel casing is proposed;The rationality of the design method was verified through simulation using ABAQUS large-scale universal finite element software.
cofferdam bottom sealing concretesteel casingstress and strainthickness designnumerical simulation