Abstract: A stabilization and gripping device for use with a compression test machine to measure strain vs load characteristics of, in particular composite material uni-directional ply specimens, includes a guide sleeve, two hollow open ended end-blocks adapted to slidably fit within the guide sleeve and to co-operate with parts of the machine for applying compressive forces to the specimen, and two pairs of collets each pair for gripping a separate one of two ends of the specimen, the collets having a planar gripping inner surface, at least one outer surface tapered with respect to the gripping surface and corresponding to a tapered inner surface of the end blocks, and a planar outer surface for co-operation with a substantially planar inner surface of the end blocks so that the collets may be non-rotatably inserted in the end blocks in a position in which the respective inner surfaces are parallel and pairs of the inner surfaces define a location for the specimen ends.

Abstract: Apparatus for limiting the buckling of an elongate test specimen during a compression test comprises a stabilizer through which the specimen 6 passes when assembled into a testing machine, the stabilizer having a body 1, 4 which is arranged to hold stiff stabilizing rods 2, 3 adjacent to those opposite faces of the specimen liable to buckle. The rods 2, 3 are adjustable to accommodate specimens 6 of different thicknesses. The stabilizer slidably engages the specimen grips 11 of the testing machine and is supported thereby so that premature shear failure of the specimen adjacent to the grips is also prevented.