## 5 Results  
### Ground Surface Acceleration Values and Soil Amplification  
Nonlinear analyses (NL) in the study were performed using Deepsoil v7.0 software. The Deepsoil software, which was preferred in this study, was first developed in 1998 based on the working principle of one-dimensional soil behavior analysis. With Deepsoil, both equivalent linear and nonlinear analyses can be performed, with analyses conducted in both frequency and time history domains [28]. As a result of 4 drillings obtained from the Adapazari region, site-specific soil dynamic parameters were determined, and 88 nonlinear analyses (NL) were performed using two different scaling methods. When the Morgan Hill earthquake, used in the analysis of the BH-1 well, one of the drillings in the region, is examined, the peak ground acceleration (PGA) is 0.689 g, and its variation depending on the depth is shown in Figure 12. In both scaling methods, the acceleration is initially damped, and then an increase towards the surface occurs. Sc-1 scaling achieved greater acceleration at the surface than Sc-2. In the unit deformation change, it was determined that both scaling methods showed similar behavior, but Sc-2 at 11 m and Sc-1 at 3.5 m reached higher deformation levels. As a result of the soil amplification analysis, two different scaling methods in the BH-1 well were compared with the surface acceleration values (Figure 13). Here, we can see the change between the acceleration at the surface and the acceleration from the bedrock. There is a difference between the Parkfield 02 earthquake and the bedrock earthquakes due to scaling. In addition, the peak points of the change in the surface (Layer-1) of the earthquake passing through the layers from the bedrock to the surface show the soil amplification effect. From these analyses, the spectral parameters of the surface soil were determined. Additionally, as a result of these analyses, Semi-Static Acceleration Response Spectrum (PGA) values, known as in situ design spectra, which represent 5% damping of the spectral velocity of motion between the bedrock and ground surface in the Fourier amplitude spectrum, were also obtained. The design response spectrum represents the maximum response of an area with a certain damping feature (5%) to different earthquake forces over various periods. Figure 11: The difference in acceleration of two different scaling methods. The design spectra are used to determine the earthquake load in new buildings. Comparison graphs of PGA values were created for the periods T = 0.01 s, T = 0.1 s, and T = 1.0 s. These three periods are preferred as a comparison to highlight their importance in building design and to provide insights into surface movement. When these values were compared to the PGA values in the bedrock, amplification (AMP) values were obtained. Comparisons were made in these three periods using both scaled records (Sc-1 and Sc-2) (Figure 14). Amplification values obtained from two different scaling methods in three different periods were compared. Although highly similar values were observed at T = 0.01 and 1.0 s (m: 0.9664 and 0.9755), it was found that they showed less similar behavior at T = 0.1 s (m: 0.8668) (Figure 15). The periods in which soil amplification will occur depend on the thickness of the soft soil layer and the speed of the earthquake wave. The period of maximum amplification (T\({}_{0}\)) is defined as the dominant period of the ground [45]. The soil amplification ratio is obtained by the ratio of the response spectrum formed on the surface to the bedrock response spectrum. Figure 12: Variation of peak bedrock acceleration and shear strains along the profile of the BH-1 e: Morgan Hill earthquake. Figure 13: Comparison of surface accelerations with two different scalings at point BH-1. It was determined that the amplification ratios varied up to 2.7 in the nonlinear analysis results using 11 different scalings in each borehole. It was determined that the amplification effect was higher, especially after T = 1.0 s, i.e., at high periods.