Effect of Prestressing on Elastica Arches

Abstract

Symmetrical and asymmetrical buckling of a prestressed arch and its equivalent rigid arch framework are investigated using a nonlinear finite element model. A corotational formulation of a three‐dimensional beam element is employed to perform large displacement, large rotation analysis. Comparisons are made between buckling loads of a class of circular and elastica (shape of prestressed arch) arches with the same rise‐to‐arch length ratios. It is found that for steep arches the effect of arch shape on the buckling load is significant, and arches that are to be considered equivalent to prestressed arches should be assumed to have elastica shapes. It is shown that the residual compressive stresses that result when the prestressed arch framework is formed have a negative effect on stability of its members, and that this is more pronounced for asymmetrical modes of buckling.