Second order elastoplastic behaviour of telescopic steel props

Abstract

This paper studies the behaviour of telescopic steel props used to prop building slabs. The proposed numerical model is formed by two straight elements which intersect at an angle and have elastic connections at its ends. The model has two types of non-linearities: geometric (second order theory) and mechanic (elastoplastic behaviour of the ring shaped cross-section). The model is calibrated by the results of load tests of real props. It allows a good forecast of the ultimate load of slender props. The forecast is not so good for short props. The model is not adequate to predict the vertical displacements of the head of the props.