Robust layout optimization of stiffened plate structures under load uncertainty

This paper proposes a robust structural layout optimization method for stiffened plate structures under load uncertainty, enabling the simultaneous optimization of stiffener layout and size. Based on the ground structure method, a robust optimization model is established in which the radii of circular beam sections representing the stiffener are selected as design variables, the total structural mass is imposed as a constraint, and a weighted combination of the expectation and variance of structural compliance under uncertain loading is taken as the objective function. The analytical sensitivity formulations of the expectation and variance of structural compliance, as well as the mass constraint with respect to the design variables, are deduced in detail. The method of moving asymptotes (MMA) is adopted to solve the proposed robust layout optimization problem. Finally, two numerical examples are performed to verify the effectiveness and applicability of the proposed method.