# Shaking Table Testing of Liquefied Soil Layer Located in the Bottom Slab of a Subway Station
## 5 Conclusions  
In this study, the seismic response of subway station structures with liquefied soil layers in the bottom plate was investigated via shaker tests. The results of the tests on foundation soils and station structures were analyzed, and the following conclusions were obtained:  
1. As the seismic intensity increases, the saturated sandy soils at the base of the structure liquefy to a higher degree, while the saturated sandy soils at other locations liquefy to a lower degree. This is due to the fact that the structure itself is less loaded and impermeable, meaning the saturated sandy soil below the structure is easy to liquefy. Conversely, the unsaturated sandy soil itself is more loaded and permeable, and so the saturated sandy soil at other locations is not easy to liquefy.
2. There is no water spraying or sand bubbling on the surface of the modeled soil, but there is still soil subsidence, and the modeled soil on both sides of the structure within a certain range is significantly damaged.
3. When the intensity of the seismic wave is small, the main frequency of each point does not obviously change. With an increase in the seismic intensity, the main frequencies of the points closer to the structure are altered from high frequency to low frequency, while the main frequency of the points farther away from the structure still does not obviously change. This indicates that the working condition of the soil is more obviously influenced by the structure than seismic wave size.
4. The acceleration response of the columns at the platform level is maximized. The acceleration response at the bottom of the column is greater than that at the top of the column for the same seismic wave. In the case of the same seismic intensity level, when the seismic intensity is small (0.1 g, 0.2 g), the acceleration response at the top of the column for the Ming Shan wave is larger than that of the Beijing Hotel wave. Conversely, when the seismic intensity is large (0.3 g to 0.6 g), the acceleration response at the top of the column for the Ming Shan wave is smaller than that of the Beijing Hotel wave. However, the acceleration response at the bottom of the column for the Beijing Hotel wave is always larger than that of the Ming Shan wave.
5. The maximum dynamic strain peak of the center column of the station occurs at the bottom of the center column of the platform level, the trend of tensile strain and compressive strain is symmetrically distributed, and the maximum dynamic strain of the slab occurs at the bottom slab of the station hall level.  
Methodology, S.M. and L.T.; Validation, S.M. and L.T.; Data curation, S.M.; Writing--original draft, S.M.; Writing--review and editing, S.M. and Z.W.; Project administration, L.T. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by the National Natural Science Foundation of China, grant number 42072308.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Data are contained within the present article. Other data presented in this research are available in [23,24].  
**Conflicts of Interest:** The authors declare no conflict of interest.