| Because recoverable structure can not only ensure the safe and timely use of post earthquake but also can achieve obvious economic benefits,therefore,whether the structure can be repaired after the earthquake,the repair time and repair costs are more and more concerned by government departments and engineers.In this paper,a kind of high strength C shaped shell steel column with a certain self reset function and excellent vertical tensile performance was proposed,The present paper was focused on the axial compression stability and recovery of recoverable C shaped shell steel column by numerical analysis and laboratory test.A research was carried out mainly as following:(1)Based on'tape effect',design of C shaped shell column with large lateral deflection and threshold buckling.The steel column is light,high strength and can quickly restore its normal use after a strong earthquake.The effects of various geometric parameters on the flexural behavior of high strength and C shaped shell were analyzed.The analytical solution of the bending moment of the tape spring in reverse bending and forward bending is deduced.The validity of the formula and the validity of the finite element model are verified by comparing the results of the formula with the finite element results.(2)Based on the shallow shell theory,the basic differential equation of simply supported C shaped shell with axial compression was established,approximate solution of basic differential equations using Galerkin method and obtain critical stress formula.From the case of fixed and simple support,buckling mode,eigenvalue buckling load,nonlinear buckling load and nonlinear buckling state of high strength and C shaped shell were researched by the eigenvalue buckling analysis and nonlinearbuckling analysis.In study,the effects of various geometric parameters on the axial compression buckling behavior of high strength and C shaped shell were analyzed.Based on the critical stress formula,the buckling load model was assumed,based on a large amount of finite element data,a practical formula for the buckling load of simply supported C shaped shell under axial compression was presented,using the same method to obtain the buckling load formula of the C shaped shell with axial compression,the validity of the finite element model and formula was verified by the experimental results.(3)Through the cold rolling,cold bending and heat treatment of the spring steel sheet,the C shaped shell with high strength,large elastic deformation and the effect of the tape measure can be prepared.The axial compression tests of the recoverable C shaped shell steel column model and steel column were designed and carried out,and the axial compressive behavior and the recovery performance of the recoverable C shaped shell steel column were studied.The finite element of each specimen was carried out considering the initial geometric imperfection,and the rationality of the ABAQUS finite element model was verified by the test results.Through the finite element analysis,the formula of the threshold buckling load of the recoverable C shaped shell steel column is fitted,and the formula of threshold buckling load of the recoverable C shaped shell steel column is fitted. |
PDF Full Text Request