Deflection And Stability Analysis Of Two-hinged Castellated Steel Arches

The castellated steel arch is widely used in engineering practice due to its advantages,such as large span,light weight,high bearing capacity,economic and aesthetic benefit,etc.However,the mechanical property of arch is more complicated than the straight beam,and the web openings can alter the stress distribution.Little literature in the theoretical research of castellated steel arch can be found.Moreover,arched members are sensitive to buckling response.Hence,the theoretical analysis of the stability of the castellated steel arch is the hot point in the current research.In this paper,the castellated steel arch is compared to the sandwich curved beam,its in-plane deflection and critical buckling stress are derived by energy method.The application of sandwich beam theory simplifies the problem of uneven distribution of stiffness along the main axis,the shear effect at the web are considered.This paper presents the formula for the elastic critical load of the in-plane anti-symmetric instability under radial load uniformly distributed along arc length.The theoretical solution is validated by the finite element analysis performed by commercial software ABAQUS.Subsequently,the control differential equations solved by iteration method of the castellated steel arch are derived,the results are compared with finite element solutions.Finally,the deflection under three different loads is solved by iterative method.The results show that the critical load formula of the castellated steel arch without considering the shear effect cannot reflect the effect of the slenderness ratio.When the shear effect is taken into account,the critical load of the steel arch is in good agreement with the finite element results which can be applied to different member sizes.Hence,the shearing effect in the analysis of arch stability theory cannot be ignored.Moreover,the proposed governing differential equation can describe the deformation of the castellated steel arch accurately.The research results of this paper provide a reference for the design of castellated steel arch,and further promote its application in practical engineering.