Attenuation Analysis of Rayleigh Waves Used to Locate Shallow Manmade Tunnels
The Attenuation Analysis of Rayleigh Waves (AARW) algorithm was applied to multi-channel surface wave seismic data acquired at two test sites for the purpose of locating manmade tunnels in the Earth's shallow subsurface. The surface wave data were acquired by incrementally moving a 24-channel geophone array and source along a traverse oriented perpendicular to the center-line of the tunnel. The near source-receiver offsets were 3 & 6 m, respectively; the 4.5 Hz geophones were spaced at 0.5 m. The geophone array geometry was optimized for nominal tunnel depths and diameters of ~1 m. Using AARW, the authors were able to reliably determine tunnel locations and delineate void geometries. Confidence levels and uncertainties with respect to void locations and geometries are discussed herein. Electrical resistivity or GPR data were acquired along each traverse for comparison purposes. This study demonstrates that the AARW algorithm may enable engineers to detect tunnels and estimate the geometry of the same.
N. H. Putnam and X. Peng and J. D. Cawlfield and O. N. Kovin and E. V. Torgashov and P. Modur and C. Stagner and S. L. Grant and N. L. Anderson and A. Nasseri-Moghaddam, "Attenuation Analysis of Rayleigh Waves Used to Locate Shallow Manmade Tunnels," Proceedings of the 43rd U.S. Rock Mechanics Symposium and 4th U.S.-Canada Rock Mechanics Symposium (2009, Asheville, NC), American Rock Mechanics Association (ARMA), Jul 2009.
43rd U.S. Rock Mechanics Symposium and 4th U.S.-Canada Rock Mechanics Symposium (2009: Jun. 28-Jul.1, Asheville, NC)
Geosciences and Geological and Petroleum Engineering
Electrical and Computer Engineering
Leonard Wood Institute
Keywords and Phrases
Manmade Tunnels; Surface Wave Seismic Data; Rayleigh waves
Article - Conference proceedings
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