Pure compression testing of advanced fibre composites

In this paper, the efficiencies of two widely used compression testing methods (one developed at Aerospatiale and one at Imperial College, London) are compared by means of finite-element analysis. The stress distribution generated in the specimen is studied for cases of perfect test-fixture geometry, and imperfect geometry resulting from unavoidable imperfection of manufacturing, Test fixtures generate stress concentrations in the specimen at the tab tip interface, even in the perfect case, and we therefore propose a new test-fixture configuration which improves the stress distribution in the specimen (uniform and maximal loading along the gauge length). Within this new configuration, the effect of geometrical defects is also reduced. The aim is to define a reliable testing method to determine accurately the laminate compressive strength. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.