Interpretation of Interbedded Thin–Soft Layer Properties from T-Bar Penetration Tests
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 148, Issue 6
Abstract
Layered soil conditions are common in marine sediments, and deduction of strength properties for thin interbedded layers is often challenging. Full-flow penetrometers such as T-bar are increasingly being used in offshore site investigations and show high potential for differentiating the shear strength transition between layers. This paper reports the results from large deformation finite-element analysis undertaken to provide insight into the response of a T-bar penetrometer as it continuously penetrates through stiff–soft–stiff clay layers. The numerical results are validated against data from a centrifuge model test. Trapped soil is observed for any nonsmooth interface as the T-bar penetrates from a stiff to a softer soil layer, which affects the measured resistance of the soft layer. The effect of a cavity above the advancing T-bar was also investigated. The presence of a cavity can increase the sharpness of the transition in resistance from one layer to another, which thus affects estimation of the boundary of the soft layer. The evolution of trapped soil from the top layer within the soft layer, and then its erosion in the bottom layer, were explored. The research found that the measured resistance profile in the soft layer is sensitive to the strength ratio between the top layer and soft layer, but the resistance of the bottom layer is more reliable. Based on deduced measurement parameters from the resistance profile, a new interpretation framework is proposed for interpreting the layer boundaries and undrained shear strength of the interbedded soft layer.
Get full access to this article
View all available purchase options and get full access to this article.
Data Availability Statement
All data, models, and code generated or used during the study either appear in the published paper or may be obtained by contacting the corresponding author.
Acknowledgments
The authors acknowledge the financial support from the National Natural Science Foundation of China (Grant Nos. 51890912 and 51679038) and the National Key Research and Development Program of China (No. 2018YFD1100401). The research presented here was also undertaken with support from the China Scholarship Council during a 12-month secondment at the Centre for Offshore Foundation Systems at the University of Western Australia. This support is gratefully acknowledged, as is the benefit of discussion with Prof. Yuxia Hu.
References
Boylan, N., M. Long, and F. Mathijssen. 2011. “In situ strength characterisation of peat and organic soil using full-flow penetrometers.” Can. Geotech. J. 48 (7): 1085–1099. https://doi.org/10.1139/t11-023.
Dassault Systems Simulia Corp. 2014. Abaqus version 6.14 documentation. Providence, RI: Dassault Systems Simulia Corp.
DeJong, J. T., N. J. Yafrate, and D. J. DeGroot. 2010. “Evaluation of undrained shear strength using full-flow penetrometers.” J. Geotech. Geoenviron. Eng. 137 (1): 14–26. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000393.
Dey, R., B. Hawlader, R. Phillips, and K. Soga. 2015. “Large deformation finite-element modeling of progressive failure leading to spread in sensitive clay slopes.” Geotechnique 65 (8): 657–668. https://doi.org/10.1680/geot.14.P.193.
Gao, W. 2017. “Large penetration of spudcan foundation in multi-layered clays-numerical study.” Ph.D. thesis, Univ. of Western Australia.
Hossain, M. 2014. “Experimental investigation of spudcan penetration in multi-layer clays with interbedded sand layers.” Geotechnique 64 (4): 258–276. https://doi.org/10.1680/geot.12.P.194.
Hossain, M. S., M. F. Randolph, and Y. N. Saunier. 2011. “Spudcan deep penetration in multi-layered fine-grained soils.” Int. J. Phys. Modell. Geotech. 11 (3): 100–115.
Hu, P., D. Wang, M. J. Cassidy, and S. A. Stanier. 2014. “Predicting the resistance profile of a spudcan penetrating sand overlying clay.” Can. Geotech. J. 51 (10): 1151–1164. https://doi.org/10.1139/cgj-2013-0374.
Koric, S., L. C. Hibbeler, and B. G. Thomas. 2009. “Explicit coupled thermos-mechanical finite element model of steel solidification.” Int. J. Numer. Methods Eng. 78 (1): 1–31. https://doi.org/10.1002/nme.2476.
Lee, J., and M. Randolph. 2010. “Penetrometer-based assessment of spudcan penetration resistance.” J. Geotech. Geoenviron. Eng. 137 (6): 587–596. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000469.
L’Heureux, J.-S., O. Longva, A. Steiner, L. Hansen, M. E. Vardy, and M. Vanneste. 2012. “Identification of weak layers and their role for the stability of slopes at Finneidfjord, northern Norway.” In Submarine mass movements and their consequences. Advances in natural and technological hazards research, 321–330. Dordrecht, Netherlands: Springer.
Liu, J., X. Chen, C. Han, and X. Wang. 2019. “Estimation of intact undrained shear strength of clay using full-flow penetrometers.” Comput. Geotech. 115 (Nov): 103161. https://doi.org/10.1016/j.compgeo.2019.103161.
Low, H., T. Lunne, K. Andersen, M. Sjursen, X. Li, and M. Randolph. 2010. “Estimation of intact and remoulded undrained shear strengths from penetration tests in soft clays.” Géotechnique 60 (11): 843–859. https://doi.org/10.1680/geot.9.P.017.
Low, H., M. L. Maynard, M. Randolph, and D. DeGroot. 2011a. “Geotechnical characterisation and engineering properties of Burswood clay.” Géotechnique 61 (7): 575–591. https://doi.org/10.1680/geot.9.P.035.
Low, H., M. Randolph, T. Lunne, K. Andersen, and M. Sjursen. 2011b. “Effect of soil characteristics on relative values of piezocone, T-bar and ball penetration resistances.” Geotechnique 61 (8): 651–664. https://doi.org/10.1680/geot.9.P.018.
Lunne, T., K. H. Andersen, H. E. Low, M. F. Randolph, and M. Sjursen. 2011. “Guidelines for offshore in situ testing and interpretation in deepwater soft clays.” Can. Geotech. J. 48 (4): 543–556. https://doi.org/10.1139/t10-088.
Ma, H., M. Zhou, Y. Hu, and M. S. Hossain. 2017a. “Effects of cone tip roughness, in-situ stress anisotropy and strength inhomogeneity on CPT data interpretation in layered marine clays: Numerical study.” Eng. Geol. 227 (Sep): 12–22. https://doi.org/10.1016/j.enggeo.2017.06.003.
Ma, H., M. Zhou, Y. Hu, and M. S. Hossain. 2017b. “Interpretation of layer boundaries and shear strengths for stiff-soft-stiff clays using cone penetration test: LDFE analyses.” Int. J. Geomech. 17 (9): 06017011. https://doi.org/10.1061/(ASCE)GM.1943-5622.0000929.
Ma, H., M. Zhou, Y. Hu, and M. Shazzad Hossain. 2015. “Interpretation of layer boundaries and shear strengths for soft-stiff-soft clays using CPT data: LDFE analyses.” J. Geotech. Geoenviron. Eng. 142 (1): 04015055. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001370.
Martin, C., and M. Randolph. 2006. “Upper-bound analysis of lateral pile capacity in cohesive soil.” Géotechnique 56 (2): 141–145. https://doi.org/10.1680/geot.2006.56.2.141.
Meng, K., C. Cui, and H. Li. 2020. “An ontology framework for pile integrity evaluation based on analytical methodology.” IEEE Access 8 (Apr): 72158–72168. https://doi.org/10.1109/ACCESS.2020.2986229.
Nakamura, A., H. Tanaka, and T. Fukasawa. 2009. “Applicability of T-bar and ball penetration tests to soft clayey grounds.” Soils Found. 49 (5): 729–738. https://doi.org/10.3208/sandf.49.729.
NORSOK Standard. 2004. Marine soil investigations. Harstad, Norway: Norwegian Petroleum Industry.
Puzrin, A. M., T. Gray, and A. Hill. 2017. “Retrogressive shear band propagation and spreading failure criteria for submarine landslides.” Géotechnique 67 (2): 95–105. https://doi.org/10.1680/jgeot.15.P.078.
Quinn, P., M. Diederichs, R. Rowe, and D. Hutchinson. 2012. “Development of progressive failure in sensitive clay slopes.” Can. Geotech. J. 49 (7): 782–795. https://doi.org/10.1139/t2012-034.
Randolph, M., P. Hefer, J. Geise, and P. Watson. 1998. “Improved seabed strength profiling using T-bar penetrometer.” In Proc., Int. Conf. on Offshore Site Investigation and Foundation Behaviour—“New Frontiers”, 221–235. London: Society for Underwater Technology.
Randolph, M. F., and G. Houlsby. 1984. “The limiting pressure on a circular pile loaded laterally in cohesive soil.” Géotechnique 34 (4): 613–623. https://doi.org/10.1680/geot.1984.34.4.613.
Sahdi, F., D. J. White, C. Gaudin, M. F. Randolph, and N. Boylan. 2015. “Laboratory development of a vertically oriented penetrometer for shallow seabed characterization.” Can. Geotech. J. 53 (1): 93–102. https://doi.org/10.1139/cgj-2015-0165.
Steiner, A., J. S. L’Heureux, A. Kopf, M. Vanneste, O. Longva, M. Lange, and H. Haflidason. 2012. “An in-situ free-fall piezocone penetrometer for characterizing soft and sensitive clays at Finneidfjord (Northern Norway).” In Submarine mass movement and their consequences. Advances in natural and technological hazards research, 99–109. Dordrecht, Netherlands: Springer.
Stewart, D. 1991. “A new site investigation tool for the centrifuge.” In Proc., Int. Conf. on Centrifuge Modelling—Centrifuge 91. Rotterdam, Netherlands: A.A. Balkema.
Stewart, D., and M. Randolph. 1994. “T-bar penetration testing in soft clay.” J. Geotech. Geoenviron. Eng. 120 (12): 2230–2235. https://doi.org/10.1061/(ASCE)0733-9410(1994)120:12(2230).
Thai, H. T., T. P. Vo, T. K. Nguyen, and C. H. Pham. 2017. “Explicit simulation of bolted endplate composite beam-to-CFST column connections.” Thin-Walled Struct. 119 (Oct): 749–759.
Tho, K. K., C. F. Leung, Y. K. Chow, and A. C. Palmer. 2012. “Deep cavity flow mechanism of pipe penetration in clay.” Can. Geotech. J. 49 (1): 59–69. https://doi.org/10.1139/t11-088.
Walker, J., and H. S. Yu. 2010. “Analysis of the cone penetration test in layered clay.” Géotechnique 60 (12): 939–948. https://doi.org/10.1680/geot.7.00153.
Wang, Y. 2019. “Centrifuge modelling and numerical analysis of penetrometers in uniform and layered clays.” Ph.D. thesis, Univ. of Western Australia.
Wang, Y., Y. Hu, M. S. Hossain, and M. Zhou. 2020. “Effect of trapped cavity mechanism on interpretation of T-bar penetrometer data in uniform clay.” J. Geotech. Geoenviron. Eng. 146 (9): 04020078. https://doi.org/10.1061/(ASCE)GT.1943-5606.0002315.
White, D., C. Gaudin, N. Boylan, and H. Zhou. 2010. “Interpretation of T-bar penetrometer tests at shallow embedment and in very soft soils.” Can. Geotech. J. 47 (2): 218–229. https://doi.org/10.1139/T09-096.
Xu, X., and B. Lehane. 2008. “Pile and penetrometer end bearing resistance in two-layered soil profiles.” Géotechnique 58 (3): 187–197. https://doi.org/10.1680/geot.2008.58.3.187.
Yu, L., H. Zhang, J. Li, and X. Wang. 2019. “Finite element analysis and parametric study of spudcan footing geometries penetrating clay near existing footprints.” J. Mar. Sci. Eng. 7 (6): 175. https://doi.org/10.3390/jmse7060175.
Zhang, W., Y. Pan, and F. Bransby. 2020. “Scale effects during cone penetration in spatially variable clays.” Géotechnique 72 (1): 78–90. https://doi.org/10.1680/jgeot.20.P.086.
Zhang, W., D. Wang, M. F. Randolph, and A. M. Puzrin. 2015. “Catastrophic failure in planar landslides with a fully softened weak zone.” Géotechnique 65 (9): 755–769. https://doi.org/10.1680/geot14.P.218.
Zhang, W., D. Wang, M. F. Randolph, and A. M. Puzrin. 2017. “From progressive to catastrophic failure in submarine landslides with curvilinear slope geometries.” Géotechnique 67 (12): 1104–1119.
Zheng, J., M. Hossain, and D. Wang. 2017. “Numerical investigation of spudcan penetration in multi-layer deposits with an interbedded sand layer.” Géotechnique 67 (12): 1050–1066.
Zhou, H., and M. F. Randolph. 2007. “Computational techniques and shear band development for cylindrical and spherical penetrometers in strain-softening clay.” Int. J. Geomech. 7 (4): 287–295. https://doi.org/10.1061/(ASCE)1532-3641(2007)7:4(287).
Zhou, H., and M. F. Randolph. 2009a. “Numerical investigations into cycling of full-flow penetrometers in soft clay.” Géotechnique 59 (10): 801–812. https://doi.org/10.1680/geot.7.00200.
Zhou, H., and M. F. Randolph. 2009b. “Resistance of full-flow penetrometers in rate-dependent and strain-softening clay.” Géotechnique 59 (2): 79–86. https://doi.org/10.1680/geot.2007.00164.
Zhou, M., M. Hossain, Y. Hu, and H. Liu. 2013. “Behaviour of ball penetrometer in uniform single-and double-layer clays.” Géotechnique 63 (8): 682–694. https://doi.org/10.1680/geot.12.P.026.
Zhou, M., M. S. Hossain, Y. Hu, and H. Liu. 2016. “Scale issues and interpretation of ball penetration in stratified deposits in centrifuge testing.” J. Geotech. Geoenviron. Eng. 142 (5): 04015103. https://doi.org/10.1061/(ASCE)GT.1943-5606.0001442.
Zhou, M., Y. Hu, and M. Hossain. 2015. “Numerical investigation of ball penetrometer performance in dense sand overlying uniform clay.” In Proc., 3rd Int. Symp. on Frontiers in Offshore Geotechnics (ISFOG 2015), 1239–1244. Abingdon, UK: Taylor & Francis.
Zhu, B., J. Dai, and D. Kong. 2019. “Modelling T-bar penetration in soft clay using large-displacement sequential limit analysis.” Géotechnique 70 (2): 173–180. https://doi.org/10.1680/jgeot.18.P.160.
Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 148 • Issue 6 • June 2022
Copyright
© 2022 American Society of Civil Engineers.
History
Received: Mar 30, 2021
Accepted: Dec 15, 2021
Published online: Apr 8, 2022
Published in print: Jun 1, 2022
Discussion open until: Sep 8, 2022
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.
Cited by
- Yumeng Qi, Fraser Bransby, Conleth D. O’Loughlin, Han Eng Low, The Effect of Crusts on the Undrained Vertical Penetration Resistance of Pipelines, Journal of Geotechnical and Geoenvironmental Engineering, 10.1061/JGGEFK.GTENG-12267, 150, 10, (2024).