Joint width tensile shear loading

Modem adhesives usually exhibit a degree of plasticity before failure. Typically, we might find 20% shear strain at a shear stress, t, of 40 MPa. One simple predictive tool is to say that the absolute maximum strength for a lap joint is when the whole of the adhesive layer is at the shear yield strength. Thus, the maximum tensile load P which could be carried by a lap Joint of width b and length / is given by... 

Where, cris the tensile stress at failure, F is the failure load, B is the web width, and L is the joint length. For the shear joints, loading of the sample results in a complex stress state. Nevertheless, a nominal failure stress was calculated using the following relation ... 

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