Simplified Method for Spatial Evaluation of Liquefaction Potential in the St. Louis Area
As a part of an earthquake hazard mapping program being undertaken by the U.S. Geological Survey in the St. Louis metropolitan area, surficial geologic mapping and subsurface geotechnical data have been compiled into a three-dimensional geographic information system (GIS). The potential for soil liquefaction was then spatially evaluated by using subsurface information from 562 boreholes for an assumed M7.5 earthquake emanating from the New Madrid Seismic Zone. Geotechnical data (standard penetration test N-values, overburden pressure, and depth-to-groundwater) and the scenario peak ground accelerations (PGA=0.1, 0.20, and 0.30 g) were applied to evaluate the factor of safety (FS) against earthquake-induced liquefaction. The liquefaction potential index (LPI) method was used in these evaluations because it allows for calculations of FS with depth for 10-25 discrete stratigraphic horizons overlying the bedrock across the St. Louis metropolitan area. LPI values were derived from the correlation between calculated LPI values and the depths-to-groundwater within late Quaternary stratigraphic units. The St. Louis metropolitan area was then classed according to four levels of severity of risk from liquefaction: (1) no liquefaction potential, (2) little-to-no likelihood, (3) moderate, and (4) severe.
J. Chung and J. D. Rogers, "Simplified Method for Spatial Evaluation of Liquefaction Potential in the St. Louis Area," Journal of Geotechnical and Geoenvironmental Engineering, vol. 137, no. 5, pp. 505-515, American Society of Civil Engineers (ASCE), May 2011.
The definitive version is available at http://dx.doi.org/10.1061/(ASCE)GT.1943-5606.0000450
Geosciences and Geological and Petroleum Engineering
Keywords and Phrases
Hazard Mapping; Liquefaction Potential Index; St. Louis Metropolitan Area; Water Depth; Earthquake Hazard; Factor of Safety; Geologic Mapping; Geotechnical Data; Late Quaternary; New Madrid Seismic Zones; Overburden Pressures; Peak Ground Acceleration; Simplified Method; Standard Penetration Test; Stratigraphic Units; Subsurface Information; U.s. Geological Surveys; Geographic Information Systems; Geological Surveys; Soil Liquefaction; Earthquake Magnitude; Missouri; United States
St. Louis, Missouri
International Standard Serial Number (ISSN)
Article - Journal
© 2011 American Society of Civil Engineers (ASCE), All rights reserved.