New Possibilities of Combining Calculations and In-Situ Seismic Data in Railway Embankment State Survey

New possibilities of seismic technology for inspection of railway embankment soils using the impact of a moving train on the medium are considered. Records of vibrations made by a broadband velocimeter installed in the lower part of the embankment are analyzed. It is shown that the main information is contained in the amplitude value of the first vibration maximum on the vertical component A_z after filtering in the 0.01–1.25 Hz band. The value of A_z is determined by the shear modulus of the embankment soil. The results of long-term soil state monitoring of stable and unstable embankments are compared. A significant difference in the time variability of shear modulus changes for different embankments during seasonal thawing of the soil is shown. The possibility of predicting the soil state using thermal engineering calculation of the thawing process is discussed, with the recommendation to use monitoring data to obtain a more reliable result.