The seismic response characteristics of the Yellow River terrace are crucial, as it is one of the key human activity areas. Seismic response characteristics of Yellow River terrace stations in Ningxia were analyzed using strong-motion earthquake records from seismic observations in the Loess Plateau and corresponding station data, employing the Horizontal-to-Vertical Velocity Response Spectrum Ratio method. The seismic vulnerability coefficient (Kg) was computed, and the bedrock depth was estimated. The results indicate that the spectral ratio curves of the Yellow River terrace can be classified into three types: single-peak, multi-peak, and ambiguous-peak types. The predominant period of the terraces ranges from 0.12 to 1.22 s, and the amplification factor ranges from 2.87 to 10.29. The calculated Kg values range from 2.09 to 63.24, and the bedrock depth ranges from 10.68 to 168.11 m. The site's predominant period, amplification factor, high Kg values, and deep bedrock depths can significantly impact seismic design, potentially leading to greater damage during earthquakes. Based on the predominant period, Kg values, and bedrock depth, the seismic vulnerability of Yinchuan is assessed to be high.

The global increase in building collapses and damage on soft-soil sites due to distant significant earthquakes poses similar challenges for sand-blowing reclamation (SBR) sites on soft-soil layers. This study was initiated to capture the vibration characteristics of the SBR sites and to provide fresh insights into their seismic responses. Initially, considering the heterogeneity and layered structure of soil at SBR sites, we developed a novel stratified shearing model box. This model box enables the simulation of the complex characteristics of soil layers at SBR sites under laboratory conditions, representing a significant innovation in this field. Subsequently, an innovative jack loading system was developed to apply active vertical pressure on the soil layer model, accelerating soil consolidation. Furthermore, a new data collection and analysis system was devised to monitor and record acceleration, pore water pressure, and displacement in real time during the experiments. To verify the model box's accuracy and innovation, and to examine the seismic response of SBR sites under varying consolidation pressures, four vibration tests were conducted across different pressure gradients to analyze the model's predominant period evolution due to consolidation pressures. The experimental results demonstrate that the model box accurately simulates the propagation of one-dimensional shear waves in soil layers under various consolidation pressures, with notable repeatability and reliability. Our experiments demonstrated that increasing consolidation pressure results in higher shear wave speeds in both sand and soft-soil layers, and shifts the site's predominant period towards shorter durations. Concurrently, we established the relationship between the site's predominant period and the input waves. This study opens new paths for further research into the dynamic response properties of SBR sites under diverse conditions through shaking-table tests.

Local soil effect plays an essential role in estimating of earthquake damage that occurs on the existing structures and in the planning and design of the new structures. One of the most critical steps in determining the earthquake design characteristics of a region is related with determining the behavior of the layers that form the soil in that region under cyclic stresses that develop because of earthquakes. Kutahya Dumlupinar University central campus needs constant new construction as the student potential increases each year in addition to the existing building stock. For this reason, data have been collected by using microtremor at 36 points and Multichannel Analysis of Surface Waves (MASW) at 4 points to determine the mechanical and physical characteristics of soil. Data being collected by the single station microtremor method were evaluated by means of horizontal-vertical spectral ratio technique, and the dominant vibration frequency values were evaluated, and the shear wave velocities (Vs30) up to a depth of 30 m were obtained by evaluating the data collected with MASW method. By establishing the relationship of the parameters obtained from both methods with the geological units, the results about the soil characteristics of the study zone were revealed. In accordance, the middle and northwest parts of the study area were composed of rock units when compared to the southeast part, and this boundary was controlled by an antithetic fault.