MODELLING OF SHEAR SOCKETED PIERS IN ROCKS PART - 3: NUMERICAL ANALYSIS

It is widely accepted that the pier-rock interface governs the strength and load-deformation behaviour of shear socketed piers. A combined laboratory and analytical study was initiated to address these key issues. This paper; which is the third of a three part series, focuses on the important features of a newly developed plasticitybased interface model. The model describes the mechanical behaviour or rock-concrete interface. Various features of the model such as the failure criterion, plastic potential, bond degradation and dilatancy, are discussed. The isoparametric formulation of the zero thickness interface element and the implementation procedure of the constitutive laws into a standard non-linear numerical code is briefly described. A failure criterion for rock joints is developed and is shown to fit well the direct shear test data obtained for sawtooth interfaces. The predictive performance of the interface (constitutive ) model is assessed by comparing numerical results and experimental data presented in two companion papers ( Parts 1 & 2 )