Analysis of Steady Cone Penetration in Clay

In this paper, a novel finite-element procedure is used to analyze steady cone penetration in soils. Although the procedure is, in principle, applicable to clay and sand with any plasticity model, this paper is only concerned with steady cone penetration in undrained clay. The steady-state finite-element analysis focuses on the total displacements experienced by soil particles at a particular instant in time during the cone penetration test. This is possible because, with the steady-state assumption, the time dependence of stresses and strains can be expressed as a space dependence in the penetration direction. As a result, the finite-element solution of steady cone penetration can be obtained in one step. When compared with the strain path method, the present finite-element procedure offers the following advantages: (1) all equations of soil equilibrium are fully accounted for; (2) cone and shaft roughness can be taken into account in a more rigorous manner and, as a result, the sleeve friction ratio can be properly predicted; and (3) the finite-element procedure can be more easily adapted to analyze cone penetration in dilatant soils.