An analytical estimate of thermal effects in a composite bonded repair: plane stress analysis

The thermal effects due to curing of the adhesive and due to the low uniform operating temperature on crack patching efficiency in a composite bonded repair are estimated using a two-stage analysis procedure originally proposed by Rose (Int. J. Solids Struct. 17 (1981) 827). The problem is formulated for a bonded repair with an octagonal shaped patch by using the linear elasticity theory. The thermal stresses due to thermal expansion mismatch between the repaired skin and the patch are determined first as if the patch is bonded rigidly to an uncracked skin, by using the equivalent inclusion method. The stress intensity factor associated with these thermal stresses is then estimated by using the displacement compatibility method for a sandwich plate with a part-through and a debonding crack