RELATIONSHIP BETWEEN SURFACE DISPLACEMENT AND ADHESIVE PEEL STRESS INBONDED DOUBLE LAP JOINTS

For adhesively bonded double lap joints, a simple formula is developed to express the adhesive peel stress in terms of the surface out-of-pl ane displacement that can be measured to the order of < 1 mu m using t he holographic interferometry technique. In this formula, the peel str ess is proportional to the surface displacement minus the constant con traction created by the Poisson's ratio. The formula is validated by c onducting a three-dimensional non-linear finite element analysis that simulates the holographic interferometry technique.