Residual strength and damage characterization of repaired glass/epoxy composite laminates using A.E. and D.I.C

In this paper, the effect of introducing different phases of fibre reinforcement in epoxy matrix at the dressed site in adhesively bonded external patch repair for damaged glass/epoxy composites under in-plane compressive loads was investigated. Three repair materials consisting of an epoxy matrix reinforced with either micro sized particulate fibres, chopped short fibres or continuous fibres were used in this study. Since this investigation extensively focuses on the effect of different types of fibre reinforcements on residual compression properties of repaired glass/epoxy composite laminates, the external patches were avoided. Acoustic emission (AE) and digital image correlation (DIC) were utilized to form qualitative and quantitative assessments of the damage progression profile. The compression results illustrate that reinforcing the epoxy adhesive material with glass fibres significantly increased the residual compression strength of repaired glass/epoxy composite specimens. In particular, the use of chopped fibre reinforced adhesive repair material improved the average residual compressive strength by 18.91% in comparison to the specimens conventionally repaired using neat epoxy resin.