The Deformation of the Adherends in an Adhesive Joint Undergoing Water Uptake

Beam and elasticity theory have been applied to the deformation observed to occur when a model adhesive joint is exposed to water. The adhesive joint is comprised of a thin microscope cover slip/adhesive layer/rigid substrate sandwich.

The presence of damped normal displacement waves in the cover slip, predicted to exist in the joint in regions of negligible water concentration, has been confirmed by measurements on photographs of interference patterns generated with an optical interferometer.

A “theory assisted” fit for the normal displacement has led to an improved fourth derivative, and this has enabled a better estimate to be made for the distribution of normal swelling stress.