Investigation of the effect of ground motion selection on the behavior of vertically loaded piles

The Kahramanmaraş-centered earthquakes that occurred on February 6, 2023 affected Turkey deeply and reminded us of the importance of earthquake-resistant design with painful losses. The design of structures affects their performance under seismic loads. In this study, by examining the ground survey reports from the Public Procurement Agency EKAP website, a 30x30 m raft foundation and a 30x30 m piled raft foundation were modeled on the ground that was created as close to reality as possible. The piles are designed with a diameter of 0.80 m under the foundation of the building, a grid of 2.50 x 2.50 m and a length of 20.00 m to transfer the loads to solid ground. A uniformly distributed load of 100 kN/m2 was loaded on the modeled raft foundation. The material model chosen for the floors is the Hardening Soil material model. Two-dimensional dynamic analyzes were carried out with the PLAXIS 2D program, which works with the finite element method. 15 different earthquake acceleration records for 2 different sections were used in the analysis. Istanbul Şile Ağva district was selected in the earthquake acceleration record selection. Considering the seismology and active fault map of the region, equal acceleration records, five each from strike, normal and reverse slip faults, were selected. According to the earthquake records selected as a result of the analysis, different displacements, bending moments, normal and shear forces were formed in the model. The relationship graphs of maximum ground acceleration (PGA), Arias density, maximum ground velocity (PGV), Housner density and maximum displacement (PGD) parameters with displacement, bending moment, axial and shear force as a result of dynamic analysis were examined. As a result of the analysis, it was observed that adding piles to the superstructure reduced settlements, bending moments, axial and shear forces. The selection of earthquake records in building design is very important as it helps determine the potential earthquake forces that may affect the structure. This study aims to observe which parameters give more effective results in earthquake record selection and the effect of piles on the model.