Studies on performance of curved beam finite elements for analysis of thin arches

Abstract The finite element model with cubic polynomial shape functions to analyse thin arches has been modified to relieve membrane locking effects and thus to achieve better performance. Two different ways of improving the element stiffness have been studied, one by adopting the reduced integration technique and the other by adopting a least square fit to achieve field consistency for membrane strains. The curved cantilever beam of Kikuchi and two fixed circular arches of Dawe having different ratios of radius to thickness (one deep, the other shallow) were studied by using the improved models. The results obtained by the improved models are compared with those of others. The model with three point integration for membrane energy gives, as expected, identical results in comparison with field consistency. The model with two point reduced integration in membrane and four point integration for bending has been found to be superior in convergence.