Instrumented Becker Penetration Test. II: iBPT-SPT Correlation for Characterization and Liquefaction Assessment of Gravelly Soils
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 143, Issue 9
Abstract
The Becker penetration test (BPT) is a widely used tool for the characterization of gravelly soils, especially for liquefaction assessment. An instrumented Becker penetration test (iBPT) was developed and integrated into the standard, closed-ended Becker drill string. The iBPT produces a continuous profile of energy-normalized blow count values , which are computed using the acceleration and force measurements recorded directly behind the driving shoe. The profile is repeatable and unaffected by hammer driving energy or accumulated shaft resistance. This paper presents the correlation between iBPT and standard penetration test (SPT) values, which is necessary for performing liquefaction assessment in gravelly soils. In developing this correlation, field variability was addressed by comparing median iBPT and SPT values from adjacent soundings over geologically consistent depth intervals. A framework was also developed to assess and, when appropriate, correct for gravel influence on measured SPT blow count values. This framework uses SPT blows per inch as well as physical evidence from SPT and adjacent Sonic samples. The correlation factor between iBPT and SPT is shown to be a constant value of 1.8 and independent of soil type or penetration resistance magnitude.
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Acknowledgments
The authors appreciated the funding and support provided by the Division of Safety of Dams (DSOD) of the California Department of Water Resources (David Gutierrez and Richard Armstrong) and Los Angeles Department of Water and Power (Craig Davis and Adam Perez). The support of Bill Sluis, Daret Kehlet, Jon Pearson, Kevin Kuei, and Chris Krage of the Department of Civil and Environmental Engineering at the University of California, Davis, is also greatly appreciated. In addition, the support and collaboration of AMEC Foster Wheeler (Marty Hudson and Alek Harounian), AECOM (Wolfgang Roth and S. Nesarajah), GeoPentech (Jon Barneich, Andrew Dinsick, and Doug Wahl), and Great West Drilling (Jim Benson) is appreciated.
References
ASTM. (2010). “Standard test method for energy measurement for dynamic penetrometers.” ASTM D4633-10, West Conshohocken, PA.
ASTM. (2011). “Standard practice for classification of soils for engineering purposes (Unified Soil Classification System).” ASTM D2487-10, West Conshohocken, PA.
Cao, Z., Youd, L. T., and Yuan, X. (2013). “Chinese dynamic penetration test for liquefaction evaluation in gravelly soils.” J. Geotech. Geoenviron. Eng., 1320–1333.
Daniel, C. R., Howie, J. A., Campanella, R. G., and Sy, A. (2004). “Characterization of SPT grain size effects in gravels.” Proc., 2nd Int. Conf. on Site Characterization (ISC’2), Millpress, Rotterdam, Netherlands.
DeJong, J. T., et al. (2017). “Instrumented Becker Penetration Test I: Equipment, operation, and performance.” J. Geotech. Geoenviron. Eng., 04017062.
Ghafghazi, M., DeJong, J. T., and Wilson, D. W. (2017). “Evaluation of becker penetration test interpretation methods for liquefaction assessment in gravelly soils.” Can. Geotech. J., in press.
Harder, L. F., Jr., and Seed, H. B. (1986). “Determination of penetration resistance for coarse-grained soils using the Becker Hammer Drill.” College of Engineering, Univ. of California, Berkeley, CA.
Idriss, I. M., and Boulanger, R. W. (2008). “Soil liquefaction during earthquakes.”, Earthquake Engineering Research Institute, Oakland, CA.
Kulhawy, F., and Trautman, C. H. (1996). “Estimation of in situ test uncertainty: Uncertainty in the geologic environment: From theory to practice.” Proc., Uncertainty ‘96, ASCE, Reston, VA.
Rogers, J. D. (2006). “Subsurface exploration using the standard penetration test and the cone penetrometer test.” Environ. Eng. Geosci., 12(2), 161–179.
Rollins, K. M., Diehl, N. B., and Weaver, T. J. (1998). “Implications of Vs—BPT correlations for liquefaction assessment in gravels.” Geotechnical earthquake engineering and soil dynamics III, Vol. 1, ASCE, Reston, VA, 506–507.
Sy, A., and Campanella, R. G. (1994). “Becker and standard penetration tests (BPT-SPT) correlations with consideration of casing friction.” Can. Geotech. J., 31(3), 343–356.
Sy, A., and Lum, K. K. Y. (1997). “Correlations of mud-injection Becker and standard penetration tests.” Can. Geotech. J., 34(1), 139–144.
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©2017 American Society of Civil Engineers.
History
Received: Sep 10, 2015
Accepted: Jan 26, 2017
Published online: Jun 15, 2017
Published in print: Sep 1, 2017
Discussion open until: Nov 15, 2017
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