BURST PROCESS OF STRETCHED FIBER-BUNDLES

A probabilistic delineation of the burst process of fiber bundles is proposed. It is shown that a burst process is governed by its rupture equation whose solution is fully characterized by the corresponding load function, which has a simple relation to the initial disorder. The extremes of the load function determine the criticalities of a burst process. According to burst size and influence on the whole bundle, the critical phenomena are divided into three categories: globally critical, subcritical, and quasicritical. As the number of fibers N in a bundle tends to infinity, the sizes of critical regions relative to N tend to zero. Rupture beyond critical regions is stable, whereas rupture in critical regions is rather unstable: A small increase of the external force may lead to an avalanche, i.e., a failure of a large number of fibers. Avalanches occur only in critical regions. © 1994 The American Physical Society.