The present research deals with structural topology optimization for multiple load cases. The problem is approached from a min-max perspective by applying the Kreisselmeier-Steinhauser function to the objectives corresponding to the individual load cases. It is shown that this method can be used to obtain results that are superior to those generated using other approaches. The study also investigates the plausibility of constraining the maximum local stress for multiple load cases using a single constraint defined as the Kreisselmeier-Steinhauser aggregate of the local stress values for a given load case. Results indicate that this formulation can be effective when used alone as well as in combination with stiffness constraints. Lastly, a new, two-phase algorithm for mesh-refinement is introduced. When used in combination with nine-node Lagrange elements, this refinement strategy can produce smooth, well-defined topologies and reduce hinges with minimal computational expense. |