THE DEFORMATION OF MULTILAYERS BY LAYER-NORMAL COMPRESSION - AN EXPERIMENTAL INVESTIGATION

In this paper, experiments are described which were carried out to inv estigate the initiation and amplification of structures which form whe n a multilayer is compressed normal to the layering. The multilayers w ere made up of either putty or paraffin wax and an attempt is made to relate the structures that form to those predicted by the various theo ries which consider the deformation of either a single layer, a multil ayer or an anisotropic material when compressed normal or at a high an gle to the layering or fabric. The experiments give an insight into th e temporal and spatial relationships between the various types of stru ctures that form by showing clearly how the initiation and growth of o ne type of structure such as a boudin can provide the local perturbati on necessary for the initiation of other structures such as internal p inch-and-swell structures or normal kink bands.