Field Test of High Density Surface Wave Survey for Investigation of Railway Embankment in Permafrost Region

The opening of the Qinghai-Tibet Railway, which runs across the permafrost region on the Qinghai-Tibet Plateau, leads to an increasing concern for the stability of the embankment. The maintenance of the railway and assessment for its influence to the permafrost require an effective investigation method. The authors carried out a field test and studied the applicability of High Density Surface Wave Survey (HDSWS) for the investigation. The field test was carried out on the natural ground and the railway embankments with various soil structures. For data processing, first, the phase velocities of Rayleigh wave were estimated from the recorded seismic data. Then, the shear wave velocity (Vs) profiles were calculated by multi-mode phase velocity inversion. The results revealed the Vs structure of the embankment as well as the natural ground. Being coincident with soil structure of the embankment and borehole data on the natural ground, the test result shows that the HDSWS is effective for permafrost investigation.