PHOTOELASTIC DETERMINATION OF STRESS INTENSITY FACTORS TO STUDY INTERACTION EFFECTS FOR CRACKED HOLES

Abstract

Presence of fastener holes is quite common is engineering structures. Interaction effect of holes increases the complexity of stress field when one or more of these holes have crack at its edge. A typical case will be when a series of interacting cracked holes are present in a structure. To carry out hole interaction study, three sets of specimens with three specimens in each set were considered by varying row separating distance and crack length. Mixed mode stress intensity factors were determined for each specimen using Smith's photoelastic"approach. Experimental results show that for the range of crack length to hole spacing ratios considered in the present study, the effects of interaction can be reduced by displacing alternate holes from a single row of interacting holes, to form another parallel-staggered row.