Finite element modelling of a deep sea clay in long-term laboratory creep tests

H. G. Brandes
M. H. Sadd
A. J. Silva

Abstract

A new finite element program is introduced and its predictive capabilities are compared to results from two long-term, drained laboratory creep tests. The constitutive behaviour is based on Cam clay critical state plasticity theory. Creep is computed using either Singh-Mitchell's three-dimensional equation or Taylor's secondary compression relationship. The experimental creep data include a triaxial specimen subjected to two deviatoric stress increments and a one-dimensional consolidation specimen subjected to three vertical stress increments. In addition, the pore pressure behaviour following an increase in stress is examined in the triaxial sample. Predictions compare favourably to test data, which provide confidence for applying the chosen constitutive model and numerical formulation to solve seabed-related problems on the continental slope.