Stress calculation and optimization in composite plates with holes based on the modified integral equation method

The integral equations are written for multiple connected anisotropic plates in a simple form based on the simple dependencies between the Lekhnitskii complex potentials and stress and strain. The numerical method for solving integral equations is developed by the mechanical quadrature method for systems of holes, which takes into account their eigen-solutions. Simplicity, precision of the approach and stability of obtained algebraic equations is illustrated in determination of hole shapes with low stress concentration; study of high stress concentration at slit of arbitrary width (additionally used asymptotic method); calculation of the stress with controlled accuracy for a large number of holes.