# Shaking Table Testing of Liquefied Soil Layer Located in the Bottom Slab of a Subway Station
## 1 Introduction  
One of the catastrophes brought on by earthquakes is the liquefaction of sand. The phenomenon of liquefaction in sandy soils has been documented in numerous seismic events. [PERSON] et al. [1] examined the seismic damage caused by the Tangshan earthquake in 1976. They discovered that both the Luanhe impact plain and the coastal plain displayed significant and severe liquefaction of sandy soils. [PERSON] [2] carried out a comparative investigation into the effects of the Tangshan earthquake on the Beijing area. The authors observed the occurrence of sand liquefaction phenomena simultaneously in the densely populated regions of the ancient river channels, particularly along the Chaobai River. Over 1000 locations experienced the discharge of water and sand, resulting in the subsidence and tilting of multiple granaries. [PERSON] et al. [3] conducted an investigation into Nepal's 2015 earthquake. They discovered that the liquefaction of sandy soil caused the Nepal Engineering College building to move. [PERSON] et al. [4] examined the damage caused by the 2011 Christchurch earthquake in New Zealand. This earthquake is thought to have been the first in which liquefaction caused the majority of the damage. [PERSON] et al. [5] conducted a field investigation of the seismic damage caused by the 2011 Christchurch earthquake in New Zealand. The earthquake caused significant damage to buildings, dams, and underground lifeline facilities, as supported by the available evidence. The 2010 Haiti earthquake, the 1995 Kobe earthquake, the 2011 Tohoku earthquake, and the 2008 Wenchuan earthquake all involved liquefaction and resulting structural damage to buildings. This means that the study of sand liquefaction must receive adequate attention. Currently, researchers are conducting relevant studies and are making significant progress in investigating the seismic response of underground structures in the presenceof liquefied soil. [PERSON] et al. [6; 7] conducted a significant study on the seismic response of a hetero-span subway station at a liquefied site using numerical modeling and shaking table experiments. In a study conducted by [PERSON] et al. [8; 9; 10; 11], shaking table tests were performed to investigate the seismic damage characteristics and dynamic damage characteristics of a three-story, three-span standard station located at a liquefied site. [PERSON] et al. [12; 13] conducted pertinent investigations on subway stations with irregular sections in liquefied foundations via shaking table tests. Furthermore, [PERSON] et al. [14] investigated the seismic response of rectangular tunnels in liquefied soils using shaking table tests. They found that liquefied soils have a seismic isolation effect and reduce the acceleration of the upper soil layer. [PERSON] et al. [15] used an elastoplastic finite element dynamic analysis procedure to describe in detail the seismic response and seismic performance of shield tunnel joints under liquefied sites. [PERSON] et al. [16] performed a numerical analysis of a two-layer, three-span island station on a liquefied foundation to derive the liquefaction distribution of soil around the structure and establish the deformation law of the structure. [PERSON] et al. [17; 18] investigated the seismic response of shield tunnels in liquefied interbedded soils using numerical simulations. They found that both the arch shoulders and the tunnel footings are potentially at risk of damage in liquefied soils. [PERSON], [PERSON], et al. [19; 20] investigated microscopic properties, such as the shape of soil particles and the contact characteristics of soil grains, via numerical simulation and triaxial testing. They also explained the influence of the microscopic action mechanisms of soil on its macroscopic performance. At present, significant progress has been made in studying the seismic analysis of underground structures situated in liquefiable areas, with investigations encompassing their seismic behavior and methods of damage.