Methodology for Optimizing Structural Masonry Positioning and Width to Minimize Lateral Displacements in Buildings under Earthquakes via the CIOA

Abstract Seismic loads can induce significant lateral displacements that compromise the stability and safety of buildings. One effective strategy to mitigate these effects is the use of masonry infills, modeled as diagonal truss elements, to enhance the lateral stiffness of the structural system. This study proposes a novel optimization-based methodology to reduce story drifts by strategically selecting control floors, defined as the levels where masonry infills most effectively contribute to lateral resistance. The methodology employs the circle-inspired optimization algorithm (CIOA) to simultaneously determine the optimal placement of these control floors and the ideal width of the masonry infills. The proposed approach is evaluated through both time-domain analysis and the response spectrum method. Numerical results demonstrate that positioning masonry on the second floor leads to a reduction of up to 39% in maximum displacement and 71% in maximum story drift. In contrast, usual design approaches resulted in increases of 46% and 41% for these parameters, respectively, when compared with the method described in this paper. These findings confirm the superior performance of the proposed method. By integrating optimization techniques with masonry placement, the methodology provides a practical and cost-effective solution for improving seismic performance, offering designers an efficient tool to control vibrations and lateral displacements in reinforced concrete buildings.