Spectral analysis of surface waves (SASW) is a non-destructive test method to determine subsurface stiffness profile (in-situ shear wave velocity and small strain shear modulus) with depths varying from 0.1 ft up to 300 ft. The test is based on the dispersive nature of Rayleigh waves, which are used to calculate the shear wave velocity. The use of a source that produces constant impact energy improves the coherence values – which directly affect the quality and acceptability of SASW results. Details of this test can be found in Heisey et al. 1982; Nazarian and Stokoe 1983; Nazarian and Stokoe 1985; Sheu et al. 1986; Stokoe, Rix, and Nazarian 1991.
The shear wave velocity profile and small strain shear modulus are used in
- Non-destructive estimations of mechanical properties of a material based on correlations with shear wave velocity and small strain shear modulus
- Estimation of seismic responses of a Earth Dam
- Olson Instruments NDE -360
- SASW Bar
- 5 Hz Geophones
- Study the effect of constant and variable impact energy to generate Rayleigh waves
- Estimation of in-situ shear wave velocity profile
- Estimation of in-situ small strain shear modulus profile of the subsurface layers
- Location of sub-surface-soft zones and voids
- Thickness measurement of fill and rock layers
- Determination of abutment depth of bridges
- Condition assessment and characterization of mass concrete
- Chakraborty, Sayantan, Tejo V. Bheemasetti, and Anand J. Puppala. “Effect of Constant Energy Source on Coherence Function in Spectral Analysis of Surface Waves (SASW) Testing.” In Geotechnical Characterisation and Geoenvironmental Engineering, pp. 59-65. Springer, Singapore, 2019.
- Chakraborty, Sayantan, Tejo V. Bheemasetti, Anand J. Puppala, and Louie Verreault. “Use of constant energy source in SASW test and its influence on seismic response analysis.” Geotechnical Testing Journal 41, no. 6 (2018): 1102-1116.
- Chakraborty, Sayantan, Aritra Banerjee, Jasaswee T. Das, Leila Mosadegh, and Anand J. Puppala. “Impact of variation of small strain shear modulus on seismic slope stability analysis of a levee: A sensitivity analysis.” In IFCEE 2018, pp. 302-313. 2018.
- Chakraborty, Sayantan, Jasaswee T. Das, Aritra Banerjee, and Anand J. Puppala. “Effect of erroneous estimation of small strain shear moduli on seismic response of an earth dam.” In Indian geotechnical conference, Guwahati, India, pp. 1-5. 2017.
- Heisey, J. S., Stokoe, K. H., Hudson, W. R., and Meyer, A. H., 1982, Determination of In situ Shear Wave Velocities from Spectral Analysis of Surface Waves, Report No. FHWA/TX- 82/34+256-2, Texas State Department of Highways and Public Transportation, Austin, TX, 293p.
- Nazarian, S. and Stokoe, K. H., II, 1983, Evaluation of Moduli and Thicknesses of Pavement Systems by Spectral-Analysis-of-Surface-Waves Method, Report No. FHWA/TX-83/26+256-4,Texas State Department of Highways and Public Transportation, Austin, TX, 138p.
- Nazarian, S. and Stokoe, K. H., II, 1985, In situ Determination of Elastic Moduli of Pavement Systems by Spectral-Analysis-of -Surface-Waves Method: Practical Aspects, Report No. FHWA/TX-86/l3+368-lF 2, Texas State Department of Highways and Public Transportation, Austin, TX, 188p.
- Sheu, J.-C., Stokoe, K. H., II, Roesset, J. M., and Hudson, W. R.,1986, Applications and Limitations of the Spectral-Analysis-of-Surface-Waves Method, FHWA/TX-87/70+437-3F, Texas State Department of Highways and Public Transportation, Austin,TX, 305p.