Historical masonry structures, which constitute an important part of the historical heritage, exhibit brittle behavior under tensile stresses due to earthquakes or soil movements/settlements. Therefore, they are sensitive to deformation. The soil–structure interaction problems play an important role in the damage to historical masonry structures. Different settlements, slips, and deformations in foundations causes damage to, and/or partial collapse the load-bearing walls. This study provides a numerical simulation of a historic masonry building on the north coast of Turkey, dating from 19th century, which suffered severe damage due to soil settlement by excavation activity near the building. FE models of the building with and without the soil–structure system were created to identify the damage to the building following soil settlement. The height of the soil domain (bounded as a fixed boundary condition) was accepted in the range of 1.5 m to 15 m. The damage propagation between the numerically obtained damage and the existing damage to the building was detailed and compared. In terms of displacement, the maximum vertical and horizontal displacement values reflecting the existing damage to the building were determined as 22 mm and 85 mm, respectively. The soil depth of 6 m was also considered acceptable for deciding the soil–structure interaction. For this, the sum of the rigid basement and the soil depth can be selected to be equal to the total height of the building participating in free vibration. It was concluded that the numerical procedure employed provided an effective representation of existing damage to a building due to soil settlement. Moreover, the procedure described can be adopted for possible collapse simulation.

The using of flat slab systems is a common structural solution for residential and commercial buildings as they are a cost-effective structural solution that simplifies and speeds up the construction phase. However, the flat slab systems have complex behavior, particularly in the slab–column connection zones, because of punching shear. Therefore, to prevent brittle flat slab collapse because of punching shear, there are some conditions which must be met in regulations such as Eurocode 2, American Concrete Institute’s Code, and Türkiye Building Earthquake Code—2018. Flat slab collapses because of punching shear can be caused by deficiencies in the design phase as well as deficiencies in the construction phase. The purpose of this study is to investigate the causes of flat slab collapses due to punching shear, focusing on whether these failures arise from design or construction deficiencies. The study highlights the importance of adhering to regulations to prevent brittle flat slab collapses. A case study of an actual building collapse due to punching shear was conducted. Theoretical punching shear strength was calculated based on the Türkiye Building Earthquake Code—2018. A finite element model of the collapsed part of the building was created, and collapse mechanism simulations were performed. It was examined whether the punching collapse mechanism was caused by deficiencies in the design or the construction phase. The findings revealed the critical role of proper design phases and construction practices in ensuring structural integrity.

This study evaluates the quality of materials in reinforced concrete buildings and their compliance with relevant legislation and earthquake codes. In this scope, field observations of collapsed 400 reinforced concrete (RC) buildings in Kahramanmaraş, Adıyaman, Hatay and Gaziantep provinces, which are among the provinces affected by the Kahramanmaraş earthquakes, were conducted, general information and official documents about the buildings were collected, and detailed investigations including structural material properties were carried out. Some data was obtained from experimental studies conducted in the laboratory. The other part was obtained from reports. Differences were observed in the percentage distribution between the average compressive strength and the minimum compressive strength. In addition, factors such as the use of smooth, large-diameter stream aggregates, inappropriate granulometry, low material quality, poor workmanship, and insufficient compaction negatively impacted the building performance. Additionally, approximately 36% of the buildings were constructed with ribbed reinforcement, 31% with non-ribbed reinforcement, and 25% with both types of reinforcement. The use of ribbed reinforcement in buildings increased significantly after 1997 and its usage rate increased in the subsequent years. The findings of this study will contribute to a better understanding of the current building material deficiencies in earthquake-prone regions and provide information on strategies that should be developed in terms of building materials to improve the resilience of buildings with similar characteristics in other earthquake regions against future seismic events.