Blast Pressure Distribution on a Buried Obstacle in a Porous Wet Soil

Abstract

The paper presents a comprehensive approach to simulate the blast pressure distribution on a rigid or flexible planar or curved obstacle buried in a porous soil medium. The Lyakhov three-phase model is adopted to take into account the volumetric components of the soil medium (air, water, and solid matrix) and their properties, in the formulation of all the branches of the equation of state that simulates the soil. The present approach considers both the bulk and the shear elastic-plastic behavior, including the effect of soil pressure on the yield strength for the stress tensor deviator. Both Godunov and the variational-difference methods are applied to solve the problem of blast wave propagation within the soil medium. An example problem of an explosion in a porous medium is presented, and the analysis of the soil-obstacle interaction under the blast action using the proposed method shows good correspondence with available experimental results. The pressure distribution along the envelope of a rigid obstacle has been investigated for different standoff distances of the explosive from the obstacle as well as for different levels of soil water contents up to saturation. In addition, the plane problems of blast response of a thin-walled lining that is buried in this medium has been studied for different levels of water content and the lining's extreme deformation including its dynamic buckling under the blast high pressures was investigated.

A two-phase model to simulate the 1-D shock wave propagation in porous metal foam

“…Note that in the present paper, by analogy with paper [50] which deal with irreversibly compressible three-phase soil medium, the unloading path that is calculated according to equations (4) and (6), is very close to a straight line (Fig. 15b).…”

“…15b). Note that for sufficiently high overpressures, the active loading and unloading lines are close to each other; it corresponds to the socalled full compaction point, that is used for description of dry soil models [39,40,50]. …”

A coupled chemo‐viscoplastic cap model for simulating the behavior of hydrating cemented tailings backfill under blast loading

“…Various expressions of EOS have been adopted to represent this nonlinear bulk behavior of soil in hydrocodes. Some examples are the Lyakhov's model of the soil as a three‐phase medium , Mie–Gruneisen type of EOS , Shock–Hugoniot EOS , and so on. An EOS is a thermodynamic equation to characterize the state of matter under given physical conditions.…”

“…Modified plastic cap model. Monotonous yield functions that pertain to I 1 (the first invariant of the stress tensor) have been widely used in soil models, or even in cement backfill models for blast loading, for example, the Drucker-Prager [24,[48][49][50][51][52][53], Mohr-Coulomb [17,43], and Lundborg [58,59,61,[64][65][66] criteria, and so on. Although they work reasonably well at low pressures, the performance of these types of models is not satisfactory in high pressure conditions.…”

Riemann solver for irreversibly compressible three-phase porous media

“…), the nonlinear models taking into account the medium compaction must be used. In doing so, both two‐phase and three‐phase theories are used.…”