Skew Reinforcement Optimization in Concrete Shells subject to Uncertain Loading Conditions

In structural design, structures are often modeled using the finite element method (FEM). One of the most common element types is the shell, which is used to model surfaces in three dimensional space when the surface thickness is less than the other two dimensions. Designers are generally interested in providing a solution that respects all the problem constraints, without trying to further improve it as optimization is not trivial even if it could yield great benefit both from the economic and the construction point of view. Additionally, saving materials is one of the fundamental criteria for the sustainable approach to the design. In this paper we address the skew reinforcement design in reinforced concrete two dimensional elements (SRD2D) subject to multiple loading conditions. It consists of determining the minimum reinforcement required to respect all the constraints given by the geometric properties and the internal actions working on it, for all the loading conditions that may occur, i.e. for different combinations of internal actions acting on the element. We present a heuristic framework that guides a genetic algorithm. Computational results show the efficacy and the effectiveness of the method.