COMPRESSIVE RESISTANCE OF UNIDIRECTIONAL GFRP UNDER HIGH-RATE OF LOADING

In an attempt to determine composite strength at high strain rates, un idirectional glass/polyester and glass/epoxy composites have been test ed using the Split Hopkinson Pressure Bar (SHPB) apparatus at room tem perature. The tested materials of the polyester-based matrix are in th e range of fiber volume fraction from 0.49 to 0.67, while the epoxy co mposites have the fiber volume fraction of 0.61. The influence of rele vant parameters, namely strain rate varying from 1/10 000 s-1 to 1000 s-1, and fiber volume fraction on the composite failure strength are i nvestigated. The influence of specimen size and ratio of length-to-dia meter on the composite strength of some polyester composite specimens with different fiber volume fraction is also examined. For compressive load acting along the fiber direction, the failure mechanism is mainl y a transverse tensile failure.