Effects of PGA and soil class on the design of multi-storey reinforced concrete structures

The majority of the building stock in Turkey is composed of reinforced concrete structures, and due to its location in the Alpine-Himalayan region, earthquake risk remains a vital concern in the country. The high seismic risk in Turkey and the increase in multi-story reinforced concrete buildings make the seismic performance and cost analysis of structures a crucial factor. The seismic behavior of a building is directly related to the interaction between the three interconnected systems of the foundation system, superstructure surrounding the foundation system, and the soil medium. Therefore, to prevent significant loss of life and property during earthquakes, the design of a structure should be tailored to the type of soil. Soil class, soil bearing capacity, and other properties determined by geophysical methods are essential steps in designing a building appropriate for the soil. In this study, to observe the critical effects of soil type and Peak Ground Acceleration (PGA) on the behavior of multi-story reinforced concrete buildings, 12 models of a 12-story reinforced concrete building with the same architectural plan, consisting of 1 basement, 1 commercial, and 10 normal floors, were established for 3 different locations with various PGA values (0.140, 0.28, 0.382) and 4 different soil types (ZA, ZB, ZC, and ZD) using the IdeCAD package program. As the soil class deteriorated and the PGA rate increased, the building's period values, earthquake-induced moments affecting the structure, relative floor displacements, horizontal loads acting on the floors, and moments generated in the building's foundation increased. In addition to the analyses conducted, the formwork, concrete, and reinforcement quantities of the buildings were also compared.