Progressive failure analysis of bonded composite repairs

To study the tensile behavior of open-hole composite plates bonded with external composite patches, experimental tests were conducted and a 3-D progressive damage model is developed. Good agreement of the experimental results with the numerical predictions is obtained. Using this analysis model, the effects of several repair parameters on the failure initiation strength, ultimate strength and failure mechanism of these repaired structures are investigated. Four high stress concentration locations, where damages mostly initiate, are detected. Three types of final failure modes of these repaired structures subjected to tensile loads are concluded, with each corresponding to a different damage progression process.