Compression Strength of Polyester Resin Reinforced with Steel Wires

Abstract

The behaviour of polyester resin reinforced with hard-drawn steel wires and with fully-softened wires of the same steel has been studied in compression tests on free-standing cylinders in which the wires are parallel with the direction of the applied load. Despite the predictions of various theories of the compressive strength of composites, the two materials behave dissimilarly, and their strengths fall well below values predicted by models based on treatments of the fibres as col umns on an elastic foundation. Fibres appear to buckle into helical shapes rather than into the planar forms usually postulated, and it is likely that the lower elastic energy required for this deformation could be the factor responsible for the disagreement between theory and experiment.