Stress Distribution in Plane Scarf and Butt Joints

The stress distribution in a plane scarf joint, which may have an arbitrary angle of scarf as well as arbitrary elastic parameters for its adherends and adhesive, is analyzed. The analysis is based on the two-dimensional elasticity theory in conjunction with the variational principle of complementary energy. Minimizing the energy functional leads to a specific optimization problem with two variables for the determination of the stresses. Some typical features of the stress distribution are shown by numerical examples. Criteria for uniformly distributed adhesive stresses which are of importance in practice are deduced. The butt joint is treated as a special case of scarf joints.