MODELLING OF SOIL-STRUCTURE INTERFACE BEHAVIOUR: A COMPARISON BETWEEN ELASTOPLASTIC AND RATE TYPE LAWS

Abstract Constitutive laws for interface behaviour are needed for the finite element analysis of problems involving soil-structure interaction, such as for piles, anchors, sheet-piling, foundations subjected to inclined loadings. The aim of this paper, is the comparison of two such laws belonging to different theoretical frameworks. In order to do that the experimental results obtained by means of a specially conceived direct shear box will be shown first and the essential features of the observed behaviour will be discussed. An elastoplastic strain hardening model and an incremental law of the rate type will be then presented. It will be shown that both may reproduce reasonably well the observed results. The former law is simpler and is quite acceptable for small displacements, while the latter seems to be more appropriate when displacements are larger.