SEISMIC BEHAVIOUR OF MODERN AGGREGATE MASONRY STRUCTURES: A NONLINEAR DYNAMIC ANALYSIS

In this study, we investigate the seismic behaviour of contemporary aggregate masonry structures in high seismic risk areas, with a focus on San José, Costa Rica. Our research highlights the interconnected response of dwellings within structural aggregates and compares them to isolated configurations in seismic events. We employ finite element modelling with multi-layered shell elements to accurately capture the behaviour of reinforced partially grouted concrete block masonry. The model includes vertical and horizontal reinforcements and simulates concrete blocks, grout, and mortar as homogenized layers using the OpenSees software. We validate the model by comparing it with experimental data. Nonlinear multi-directional dynamic analyses are performed to investigate the seismic behaviour of aggregate masonry systems. The proposed model is first evaluated for isolated partially grouted reinforced concrete block masonry, and identical systems are then arranged in a row to establish normal contact between adjacent dwellings, representing the interconnected nature of these configurations. The analysis reveals significant variations in response between isolated and aggregated setups. Furthermore, the seismic capacity of systems within the aggregate differs based on their position, with distinct resistance and failure mechanisms observed among dwellings. This research provides valuable insights into the seismic performance of modern aggregate masonry systems, underscoring the importance of inter-dwelling connections in densely populated urban areas exposed to high seismic activity. The findings contribute to the development of effective strategies for designing, assessing, and retrofitting such systems, thereby enhancing resilience and safety in seismic-prone regions.