Impact of Hammock Formations on Vertical Obstructions

The paper considers scenarios of head-on impact on vertical obstacles and destruction of hummock subsurface parts represented as a discrete spherical-element medium. The issues analyzed include the 2-phase nature of interaction and destruction of a loose and connected medium and also the cyclic pattern of loading and dynamic effects emerging in interaction with the hummock keel. The contact local stress in the subsurface part is determined by solving the Hertz equation which describes the indent of a sphere into a plane slab. Structural bonds are destructed when cohesion vanishes over the sliding plane. In the initial phase, a frozen ice ridge disintegrates as an perfectly plastic body with small angle of cohesion, while the second phase is viewed as dozing the sliding prism as a loose discrete body. This model allows for spatial effects in distortion of the subsurface part of an ice ridge. The dynamic effect is noted to increase with the size of hummock fragments, hummock speed and size.