The transient motion of a dislocation with a ramp-like core

The general solution of the radiated field from a nonuniformly moving ramp dislocation with general time-dependent ramp displacement function is obtai ned. Special cases of it, for arctan displacement with certain constant or time-dependent width and step function displacement, and for motions starti ng from rest at time t=0 and moving thereafter nonuniformly, are presented. The solution is in terms of quadratures which will be evaluated when the t ime-dependent functions become known. A special case, the ramp dislocation starting from rest and moving with a constant velocity thereafter, is analy zed with particular emphasis on the wave-front and near-field behaviour. (C ) 2001 Elsevier Science Ltd. All rights reserved.