Energy-Based Topology Optimization Under Stochastic Seismic Ground Motion: Preliminary Framework

The growing availability of suitable computational resources to support the design of complex and large buildings makes the topology optimization more and more attractive to achieve high structural performances while reducing the use of building materials and thus cutting the total costs. In case of buildings under dynamic loads, displacement- and acceleration-based criteria are most commonly employed in topology optimization for preventing damage in structural components and protecting high-frequency sensitive non-structural components, respectively. The present work introduces the energy-based topology optimization of large structures as a more effective design approach to mitigate damage due to earthquake. The inherent randomness of the seismic excitation is taken into account by means of the random vibration theory, in such a way to avoid the direct integration of the motion equations for a large number of records. Topology optimization is performed via Solid Isotropic Material with Penalization (SIMP) method and resorting to an analytical evaluation of the gradient. A stationary-type stochastic seismic ground motion is considered in the preliminary framework presented in this study, whereas the final case study here discussed is concerned the search of the optimal layout for a lateral resisting system in a multi-story building subjected to earthquake.