SH-wave refraction/reflection and site characterization

Z. Wang; R.L. Street; E.W. Woolery; I. P. Madin

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USGS · 70022542

SH-wave refraction/reflection and site characterization

Z. Wang·R.L. Street·E.W. Woolery·I. P. Madin

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Abstract

Traditionally, nonintrusive techniques used to characterize soils have been based on P-wave refraction/reflection methods. However, near-surface unconsolidated soils are oftentimes water-saturated, and when groundwater is present at a site, the velocity of the P-waves is more related to the compressibility of the pore water than to the matrix of the unconsolidated soils. Conversely, SH-waves are directly relatable to the soil matrix. This makes SH-wave refraction/reflection methods effective in site characterizations where groundwater is present. SH-wave methods have been used extensively in site characterization and subsurface imaging for earthquake hazard assessments in the central United States and western Oregon. Comparison of SH-wave investigations with geotechnical investigations shows that SH-wave refraction/reflection techniques are viable and cost-effective for engineering site characterization.

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Z. Wang, R.L. Street, E.W. Woolery, I. P. Madin. 2000. SH-wave refraction/reflection and site characterization. https://pubs.usgs.gov/publication/70022542

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