Nose shape effect on high velocity soil penetration

Engineering models of high speed penetration into geological shields

“…whereτ 0 = 2κ cos μ = sin (60) τ is shear stress at failure, σ is normal stress at failure (compressive stress is considered positive), κ is the apparent cohesion, is angle of shearing resistance (angle of internal friction). Eq.…”

“…Song et al [58] studied penetration of a projectile into a semi-infinite plastic shield on the basis of dynamic and quasi-dynamic CCE models. Yankelevsky and Adin [59]; Yankelevsky and Gluck [60] proposed disk model that belongs to the class of cylindrical cavity expansion models. Yankelevsky [61] adapted this model for the case of shields with a predrilled hole.…”

Shape optimization of high-speed penetrators: a review

“…In shape optimization of projectiles penetrating into finite-thickness shields (optimization criterion is the BLV) the "averaged models" are not used; in this case incomplete immersion of the impactor into the shield at the initial and final stages of penetration is taken into account. Yankelevsky and Gluck [23] use the model suggested by Yankelevsky and Adin [24] which falls outside the scope of the above classification. Symbol "−" in column «Friction» indicates that friction is not taken into account, while "constant µ " or "constant τ " indicate that either friction coefficient or friction force per unit surface area are considered constant and non zero; "variable µ " indicates using the model with friction coefficient depending on sliding velocity, and "different models" indicates that analysis is conducted using different friction models (either a model with a constant µ and the model suggested in [25]).…”

Penetration of an exisymmetric conical hammer into frozen soil

“…For small angles at the vertex of a cone (a narrow body of revolution), the surfaces along which the soll particles are moved are similar to planes perpendicular to its axis of symmetry; in this case it is appropriate to utilize the hypothesis of "planar sections" [2,5,6]. The problem is hereby substantially simplified and is reduced to studying the motion of a medium with cylindrical symmetry.…”

“…It must be noted that the authors of [6] applied the hypothesis of planar sections with success in investigating the dependence of intrusion depth upon the shape of the nose portion of hammers with a shape unlike that of a narrow body of revolution.…”