STRENGTH OF COMPOSITE LAMINATES WITH CONTINUOUS FIBER AROUND A CIRCULAR HOLE

The strength of glass fiber woven roving composites containing a circular hole was examined. Two types of circular hole - drilled, and moulded-in - were considered. Experiments were conducted on four different sizes of hole diameter. Experimental results show that specimens with a moulded-in circular hole exhibit failure at a higher strength than those with a drilled hole and exhibit different failure mode. A strength enhancement of 28-77% as compared with drilled laminates was observed. In addition to explaining the experimental results, a simple finite element model which used the concept of the stream line to simulate the fiber configuration was used in the stress analysis of laminates with moulded-in circular holes. The numerical results may explain why the laminates with moulded-in holes are stronger than those with drilled holes.