Strain‐path analyses for arbitrary three‐dimensional penetrometers

A numerical technique has been implemented to perform strain path analyses for arbitrary three‐dimensional (3D) penetrometers. The technique is based on that developed in aeronautical engineering for the calculation of incompressible potential flows about arbitrary 3D, non‐lifting bodies. It uses a source‐density distribution on the surface of the body and solves for the distribution necessary to make the normal component of fluid velocity zero on the boundary. The surface of a 3D body is approximated by a series of plane quadrilaterals, and the integral equation for the source density is replaced by a set of linear algebraic equations which are then solved for the source densities on the quadrilaterals. The displacements and strains are eventually derived based on these source densities. A series of strain‐path analyses have been performed for cone and flat dilatometer penetrations. Results show that the soil responses to these two types of penetrometers are fundamentally different.