FINITE-ELEMENT MODELING OF A DEEP-SEA CLAY IN LONG-TERM LABORATORY CREEP TESTS

A new finite element program is introduced and its predictive capabili ties are compared to results from two long-term, drained laboratory cr eep tests on a deep sea clay, The constitutive behaviour is based on C am clay critical state plasticity theory with creep and time-dependent hardening. Creep is computed using either Singh-Mitchell's three-dime nsional equation or Taylor's secondary compression relationship, The e xperimental creep data include a triaxial specimen subjected to two de viatoric stress increments and a one-dimensional consolidation specime n 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 p rovide confidence for applying the chosen constitutive model and numer ical formulation to solve seabed-related problems on the continental s lope that are of interest to geologists, the oil industry and the navy , among others.