Comparison of method II and III in soil-structure interaction according to TBDY 2018 in different soil conditions

Turkey is located in one of the major earthquake belts in the world and earthquakes that have occurred in the past until today have caused great loss of life and property. Insufficient soil investigations, deficiencies in regulations, inadequate construction quality and local ground conditions amplify earthquake effects. Although many earthquake regulations have been used in practice from the past to the present, the first regulation that takes into account the soil effects is the Turkish Building Earthquake Code (TBDY) published in 2018. In this code, many issues related to soils are included, and the most significant addition is the structure-pile-soil interaction analyses that are made compulsory for certain structures. Structure-pile-soil interaction analyses are defined in TBDY 2018 as three different methods, Method I, Method II and Method III. In this study, the differences between two methods namely Method II and Method III in TBDY 2018 in a region with high seismicity were investigated by considering a case study. In the analysis, the effects of 7 different input motions for DD1 and DD2 earthquake levels were investigated. According to the results, the earthquake level directly affects the pile behavior. In addition, in the interaction analysis, it was observed that the earthquake data selected in the displacement method, known as Method III, did not affect the results much, and there were differences between the earthquake data in Method II (TH-Time History Method). Additionally, the shear and moment effects on the pile were obtained approximately 2 times more in Method II than with Method III. Keywords: Kinematic interaction, TBDY 2018, Time History Method, Finite Element Method, DeepSoil Program, Site response analysis