Scale Issues and Interpretation of Ball Penetration in Stratified Deposits in Centrifuge Testing
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 142, Issue 5
Abstract
A full-flow ball penetrometer is now routinely used in centrifuge testing for characterizing single-layer clay, silt, sand, and stratified soil samples. The behavior of the standard ball penetrometer (including the shaft) used in the field, penetrating through single and two-layer uniform clays, has recently been investigated. However, the ball penetrometers used in centrifuge testing has either a similar or higher area ratio (of the shaft to the ball) and significantly greater equivalent prototype diameter compared with the standard one used in the field. The thickness of the soil layers, however, are scaled accurately mimicking strength profiles in the field, leading to lower relative thickness of the soil layers. Large deformation finite element (LDFE) analyses were, therefore, carried out for the centrifuge ball penetrometers to investigate its performance in characterization of single- and double-layer clays. The results were validated against plasticity solutions and other previously published finite element (FE) results prior to undertaking a detailed parametric study, exploring a range of normalized soil properties and layer thickness. Three commonly used centrifuge balls were studied. For single-layer uniform clay, the area ratio of shaft to ball was shown to have significant influence on the deep bearing factors and the critical penetration depth of attaining that factor. For two-layer uniform clays, the undrained shear strength of the top layer was mostly underestimated because of the lower thickness of that layer relative to the centrifuge ball diameter. In addition, the shear strength of the bottom layer was mostly overestimated because of trapping of stiff clay at the base of the ball, advancing in stiff-over-soft clay deposits. To interpret a reference undrained strength profile, taking into account the scale effects of the penetrometer relative to layer thickness, a framework has been proposed accounting for these effects, with the LDFE data used to calibrate the framework.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The research presented in this paper was undertaken with support from 111 project of China (No. B13024), the Department of Industry, Innovation, Science, Research, and Tertiary Education (DIISRTE) Australia China Science and Research Fund (Group Mission ACSRF00300), and the Australian Research Council (ARC) Discovery Grant (DP1096764). The second author is an ARC Discovery Early Career Researcher Award (DECRA) Fellow and is supported by the ARC Project DE140100903. The work forms part of the activities of the Centre for Offshore Foundation Systems (COFS), currently supported as a node of the Australian Research Council Centre of Excellence for Geotechnical Science and Engineering and as a Centre of Excellence by the Lloyd’s Register Foundation.
References
Boylan, N., Michael, L., Darren, W., Barwise, A., and Brian, G. (2007). “Full-flow penetrometer testing in Bothkennar clay.” Proc., 6th Int. Offshore Site Investigation and Geotechnics Conf.: Confronting New Challenges and sharing Knowledge, Society for Underwater Technology, London, 117–186.
Carter, J. P., and Balaam, N. P. (1995). AFENA users’ manual, Centre for Geotechnical Research, Univ. of Sydney, Sydney, Australia.
DeJong, J. T., Yafrate, N. J., and DeGroot, D. J. (2011). “Evaluation of undrained shear strength using full-flow penetrometers.” J. Geotech. Geoenviron. Eng., 14–26.
Einav, I., and Randolph, M. F. (2005). “Combining upper bound and strain path methods for evaluating penetration resistance.” Int. J. Numer. Meth. Eng., 63(14), 1991–2016.
Ghosh, S., and Kikuchi, N. (1991). “An arbitrary Lagrangian-Eulerian finite element method for large deformation analysis of elasticviscoplastic solids.” Comput. Meth. Appl. Mech. Eng., 86(2), 127–188.
Herrmann, L. R. (1978). “Finite element analysis of contact problems.” J. Eng. Mech. Div., 104(EM5), 1043–1057.
Hossain, M. S., and Randolph, M. F. (2009). “Effect of strain rate and strain softening on the penetration resistance of spudcan foundations on clay.” Int. J. Geomech., 122–132.
Hossain, M. S., and Randolph, M. F. (2010). “Deep-penetrating spudcan foundations on layered clays: Centrifuge tests.” Géotechnique, 60(3), 157–170.
Hu, Y., and Randolph, M. F. (1998a). “A practical numerical approach for large deformation problems in soil.” Int. J. Numer. Anal. Meth. Geomech., 22(5), 327–350.
Hu, Y., and Randolph, M. F. (1998b). “Deep penetration of shallow foundations on non-homogeneous soil.” Soil Found., 38(1), 241–246.
Klar, A., Pinkert, S., and DeJong, J. T. (2014). “Evaluation of a logarithmic-law strength rate parameter using full-flow penetrometers.” Geotech. Res., 1(2), 53–59.
Low, H. E., Randolph, M. F., DeJong, J. T., and Yafrate, N. J. (2008). “Variable rate full-flow penetration tests in intact and remoulded soil.” Proc., 3rd Int. Conf. on Geotechnical and Geophysical Site Characterization, Taylor & Francis, London, 1087–1092.
Lu, Q., Hu, Y., and Randolph, M. F. (2000). “FE analysis for T-bar and spherical penetrometers in cohesive soil.” Proc., 10th Int. Offshore and Polar Engineering Conf., Vol. 2, International Society of Offshore and Polar Engineers, Cupertino, CA, 617–623.
Lu, Q., Randolph, M., Hu, Y., and Bugarski, I. (2004). “A numerical study of cone penetration in clay.” Géotechnique, 54(4), 257–267.
Newson, T. A., Watson, P. G., and Bransby, M. F. (1999). “Undrained shear strength profiling using a spherical penetrometer.”, Geomechanics Group, Univ. of Western Australia, Crawley, WA, Australia.
Pinkert, S., and Klar, A. (2013). “Analytically and experimentally based resistance factors for” full-flow” penetrometers.” Proc., 18th Int. Conf. on Soil Mechanics and Geotechnical Engineering, International Society for Soil Mechanics and Geotechnical Engineering, London, 781–784.
Randolph, M. F., Martin, C. M., and Hu, Y. (2000). “Limiting resistance of a spherical penetrometer in cohesive material.” Géotechnique, 50(5), 573–582.
Randolph, M. F., Wang, D., Zhou, H., Hossain, M. S., and Hu, Y. (2008). “Large deformation finite element analysis for offshore applications.” Proc., 12th Int. Conf. of Int. Association for Computer Methods and Advances in Geomechanics, Curran Associates, New York, 3307–3318.
Stewart, D. P. (1992). “Lateral loading of piled bridge abutments due to embankment construction.” Ph.D. thesis, Univ. of Western Australia, Crawley, WA, Australia.
Vallejo, L. E. (1982). “Evaluation of test methods designed to obtain the undrained shear strength of muds.” Proc., Offshore Technology Conf., Offshore Technology Conference, Houston.
Watson, P. G., Newson, T. A., and Randolph, M. F. (1998). “Strength profiling in soft offshore soils.” Proc., 1st Int. Conf. on Site Characterization–ISC ‘98, Balkema, Atlanta, 1389–1394.
Yafrate, N. J., DeJong, J. T., DeGroot, D., and Randolph, M. F. (2009). “Evaluation of remolded shear strength and sensitivity of soft clay using full-flow penetrometers.“ J. Geotech. Geoenviron. Eng., 1179–1189.
Zhou, H., and Randolph, M. F. (2007). “Computational techniques and shear band development for cylindrical and spherical penetrometers in strain-softening clay.” Int. J. Geomech., 287–295.
Zhou, H., and Randolph, M. F. (2009). “Resistance of full-flow penetrometers in rate-dependent and strain-softening clay.” Géotechnique, 59(2), 79–86.
Zhou, H., and Randolph, M. F. (2011). “Effect of shaft on resistance of a ball penetrometer.” Géotechnique, 61(11), 973–981.
Zhou, M., Hossain, M. S., Hu, Y., and Liu, H. (2013). “Behaviour of ball penetrometer in uniform single-and double-layer clays.” Géotechnique, 63(8), 682–694.
Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 142 • Issue 5 • May 2016
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Nov 14, 2014
Accepted: Oct 5, 2015
Published online: Jan 4, 2016
Published in print: May 1, 2016
Discussion open until: Jun 4, 2016
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.