Determination of the progressive collapse risk of structures taking into account soil structure interaction effect

Structures may be exposed to unpredictable loads, different from design loads, throughout their service life. Some developed countries carry out progressive collapse risk analyzes for strategically important structures with the guidelines and regulations they prepare by taking such effects into account. However, in many other countries, since the concept of progressive collapse is not yet known enough, such analyzes cannot be made and critical structures are constructed in the same way as other structures. The aim of this thesis is to investigate the effects of soil properties on progressive collapse and to examine in detail the effects of different soil types on the behavior of structures. For this purpose, reinforced concrete and steel frame samples were examined using the UFC 4-023-03 guide published by the American Department of Defense, which has been widely used in progressive collapse analyzes in recent years. Sample structures were analyzed by two different methods: linear static analysis (LSP) and non-linear dynamic analysis method (NDP) with the Alternative Path method (APM), taking into account the soil-structure interaction. The soil effect, which was taken into account with Modified Vlasov model, was taken into account by using SAP2000 and MATLAB programs simultaneously with the help of an interface coded in MATLAB. As a result of the analyses, it has been seen that soil effect could significantly change the progressive collapse resistance of the building elements in both analysis models.