SIMULATING STRESS INTENSITY FACTORS FOR ANISOTROPIC MATERIALS BY THE LEAST-SQUARES METHOD

The main purpose of this paper is to investigate the accuracy of the l east-squares method incorporating the finite element method for findin g the stress intensity factors of composite materials. Numerical simul ations in this paper indicate that the least-squares method can be use d to calculate stress intensity factors accurately, if seven or eight displacements terms are included. The calculated stress intensity fact ors by using the least-squares method can be as accurate as the calcul ated J-integrals by using the J-integral formulation. If seven or eigh t displacement terms are included, the calculated stress intensity fac tors of this method are independent of the maximum radius of the area from which data is included; furthermore, a very fine mesh is also not necessary.