Characterization of silty soil thin layering and groundwater conditions for liquefaction assessment

Autor: Rick Wentz, Sarah Bastin, Mark Stringer, Jonathan D. Bray, Michael F. Riemer, Sjoerd van Ballegooy, M. Jacka, Misko Cubrinovski, Christine Z. Beyzaei
Rok vydání: 2020
Předmět:
Zdroj: Canadian Geotechnical Journal. 57:263-276
ISSN: 1208-6010
0008-3674
DOI: 10.1139/cgj-2018-0287
Popis: Tools for characterizing thin layering and groundwater table conditions are evaluated at silty soil sites being assessed for liquefaction. Thin interlayered stratigraphy and groundwater table fluctuation are two potential causes for inconsistencies observed during the Canterbury earthquake sequence, wherein liquefaction did not manifest at several silty soil sites, despite simplified liquefaction assessment procedures indicating severe manifestations would be expected. Site investigations should capture these features to allow for improved assessment of liquefaction potential at silty soil sites. Cone penetration tests (CPTs), mini-CPTs, and sonic borings do not adequately capture thin layering. However, detailed logging of high-quality samples captures the actual in situ layering that may help explain the limitations of simplified liquefaction assessment procedures at these sites, revealing the need to understand underlying limitations in current site investigation techniques. Piezometers, sonic borings, high-quality sampling, crosshole testing, and regional groundwater maps are evaluated to assess their ability to capture complex groundwater conditions. Multiple groundwater measurement methods are typically required to characterize groundwater fluctuations. An approach to using enhanced site characterization tools is recommended for liquefaction assessments at silty soil sites with thin layering and groundwater fluctuations.
Databáze: OpenAIRE