: The vulnerability of underground structures and openings in deep jointed rock to ground shock attack is of chief concern to military planning and security. Damage and/or loss of stability to a structure in jointed rock, often manifested as brittle failure and accompanied with block movement, can depend significantly on jointed properties, such as spacing, orientation, strength, and block character. We apply a hybrid Discrete Element Method combined with the Smooth Particle Hydrodynamics approach to simulate the MIGHTY NORTH event, a definitive high-explosive test performed on an aluminum lined cylindrical opening in jointed Salem limestone. Representing limestone with discrete elements having elastic-equivalence and explicit brittle tensile behavior and the liner as an elastic-plastic continuum provides good agreement with the experiment and damage obtained with finite-element simulations. Extending the approach to parameter variations shows damage is substantially altered by differences in joint geometry and liner properties.
Today, many nations protect their critical assets through deep burial in hard rock formations. The vulnerability of these underground facilities -- including command and control facilities, weapon production and storage areas, testing facilities, nuclear waste burial facilities, and others -- to ground motions caused by explosions and earthquakes is of priority national interest. However, the response of these facilities to ground shock environments is poorly understood, and high confidence in vulnerability assessments from these stimuli is impeded with uncertainty.
