FAILURE ANALYSIS OF WOVEN-FABRIC COMPOSITES WITH MOLDED-IN HOLES

The failure strength of a woven-glass-roving composite containing a ci rcular hole has been examined. Two types of circular holes, drilled an d moulded-in, are considered Failure experiments on (0,90)(s) and (+/- 45)(s) woven-roving composites are conducted on samples with four diff erent sizes of hole diameters. Experimental results show that specimen s of (0,90)(s) laminates with a moulded-in hole exhibit failure at gre ater stresses than those with a drilled hole, whereas for (+/-45)(s) l aminates with drilled and moulded-in holes, the failure stresses are a lmost the same. The failure strengths of laminates with moulded-in and drilled holes are predicted by the finite element method. A generaliz ed stream-line model is proposed to simulate the fibre configuration a nd is used in the finite element stress analysis. The modified rule of mixtures is used to define the material moduli of laminates with a mo ulded-in hole. The Hashin strength criteria and a material degradation model are used in the strength analysis. Reasonable numerical results are obtained.