Discontinuous analysis of softening solids under impact loading

Softening solids are analysed under impact loading using a new numerical method which allows displacement discontinuities to propagate arbitrarily through a finite element mesh. The Dirac-delta distributions that arise in the strain held of classical continuum theory in the presence of strain softening are interpreted as discontinuities in the displacement held. A new finite element procedure with Heaviside jumps added to the underlying displacement interpolation basis is able to capture displacement jumps independent of the spatial discretisation. The amplitudes of displacement jumps are represented by extra degrees of freedom at existing nodes. Numerical results for mode-I and mode-II failure due to impact loading are presented. The numerical results highlight the objectivity of the approach with respect to spatial discretisation under dynamic loading conditions. Copyright (C) 2001 John Wiley & Sons, Ltd.