Fig. 1. A recent example of buried pipe detection by using surface-wave scattering.
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(Right) Fig. 2. Summary of the work by Gabriels et al. (1987).
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Historically, most of surface wave applications have followed three (3) fundamental steps:
Acquisition ->Dispersion Analysis -> Seeking the layered-earth model (Vs, Vp, h, r, etc.). The main
topics of development in recent history have been field procedures (data acquisition) and data
processing (dispersion and inversion analyses). More recently, non-shear velocity (Vs) application
of surface waves (Fig. 1) include anomaly detection, which seems to be a very useful and promising
tool that nicely compliments the capabilities of other methods (Cucunski et al., 1996; Park et al.,
1998b; Nasseri-Moghaddam, 2006; Phillips et al., 2004, etc.), and damping evaluation (Rix and Lai,
1998; etc.) A brief coverage of this historical development can be found in the 2005 special issue
of JEEG (Journal of Environmental and Engineering Geophysics) on the surface wave method.
Another historical overview can be found in Park and Ryden (2007).
20th century when Jones (1961) and other investigators used small vibrators as wave
experienced a boom in the mid-1980s when digital computers became popular. MASW was
developed on top of one of a widely-used surface wave method called spectral analysis of
surface waves (SASW) method introduced during this period. Unlike SASW, which is a
two-receiver approach, MASW adopted the multichannel (24 or more channels) concept long
used in the history of seismic exploration for natural resources.
First documented use of the multichannel approach for surface wave analysis goes back to
the early 1980s when investigators in the Netherlands used a 24-channel acquisition
system to deduce shear-wave velocity structure of tidal flats by analyzing recorded surface
approach in surface wave dispersion analysis and, in this regard, the study can be regarded
Fig. as a feasibility test of the approach for routine use in the future. Then, using
uncorrelated Vibroseis data, Park et al. (1999) highlighted the effectiveness of the approach
by detailing advantages with multichannel acquisition and processing concepts most
appropriate for geotechnical engineering applications. A subsequent boom in surface wave
applications with the MASW method for various types of geotechnical engineering projects
has been observed worldwide since that time.