Effect of plastic anisotropy of weld on limit load of undermatched middle cracked tension specimens

Plastic anisotropy may have a significant effect on the limit load of structures. The present paper shows its effect on the limit load of well-undermatched middle cracked tension specimens assuming that the base material is elastic and the weld material obeys Hill's quadratic orthotropic yield criterion in rigid-perfect plasticity. The solution is based on a kinematically admissible velocity field, which is compatible with a stress field satisfying the equilibrium equations and the yield criterion in the plastic zone. The velocity field is singular in the vicinity of the bi-material interface, which is typical for isotropic materials.