Load vertical decay

Fig. 5 explains how the eccentricity in load path, between the bottom face of the upper splice plate and its centroid, creates a moment as shear loads are transferred that can be balanced only by normal (peel) stresses developed in the adhesive. Note that this effect exists even if there is no primary eccentricity in load path of the type found in single-lap and single-strap bonded joints, for which the corresponding phenomena are explained later. In both cases, peel stresses peak at the edge of the overlap and decay to negligibility away from any discontinuities, oscillating as they do to satisfy the requirement that there is no net vertical force on either splice plate. 

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