AN ESTIMATE OF PENETRATION DEPTH OF RIGID RODS THROUGH MATERIALS SUSCEPTIBLE TO MICROCRACKING: PART 2 – VALIDATION AND PARAMETER SENSITIVITY

A simple, approximate model aimed at estimating the penetration depth of slender rigid projectiles into massive targets made of quasibrittle solids is proposed in the companion article [1]. The key ingredient for that novel analytical approach—namely, the functional dependence of the radial traction at the cavity surface on the radial velocity of the cavity expansion—is provided by postprocessing of results of particle dynamics simulations. In this article, this model is validated using experimental results on the depth of penetration of long (virtually rigid) projectiles into Salem limestone targets. Salem limestone is a typical example of quasibrittle materials with random, discontinuous and heterogeneous micro/meso structure, inherently predisposed to microcracking, which is attributed to their inferior tensile strength. Such materials are known for their pronounced scatter of experimental data. This inherent stochasticity is explored in this paper through a comparative analysis of key model input parameters; primarily, the indirect (uniaxial) tensile strength and the coefficient of friction.