Theoretical Analysis on the Characteristics of Spatial Stress Components Distribution of the Track Subgrade Strata with Hidden Columnar Cavity

In recent years, the development of urbanization is rapid, and ground collapse happened frequently. During the construction and use of engineering projects, ground collapse disasters frequently occur due to the presence of hidden cavities. Therefore, clarifying the stress distribution characteristics of the subgrade layer under the coupling of multiple factors is particularly important for ensuring ground stability. Therefore, this article conducts a theoretical analysis of the spatial stress distribution in the base layer of a railway track containing concealed columnar voids. Firstly, considering the unit gravity of the subgrade and vehicle, a spatial model was generated. Subsequently, the expressions of stress components were obtained using the theory of elasticity. The numerical simulation result of vertical stress is in good agreement with the theoretical calculation result. There are some errors in value for the radial and circumferential stress. However, the maximum error is less than 5%. Moreover, this error gradually decreases with the increase of radius, and disappears when the distance reaches three times the diameter. The present analysis indicates that the solved general solution could reflect the distribution of stress accurately, and is feasible to practical application.