Influence of Destructuration of Soft Clay on Time-Dependent Settlements: Comparison of Some Elastic Viscoplastic Models
Publication: International Journal of Geomechanics
Volume 15, Issue 5
Abstract
The time-dependent settlement of soft soils following the application of surface loading may be modeled using elastic viscoplastic constitutive models to describe the soil behavior. For applied loadings that increase the stresses toward and beyond the in situ yield stress, the predicted behavior is strongly influenced by the associated breakdown of the clay structure and the way in which this is modeled. Four elastic viscoplastic models are compared and it is shown that, despite presentational differences, all calculate creep rate in fundamentally the same manner. This paper describes some predictions for a hypothetical case prediction exercise organized recently by the Norwegian Geotechnical Institute that compared different calculation methods used in settlement analyses of soft soil. The results presented here are from a one-dimensional coupled consolidation analysis implemented in a spreadsheet-based software and using a finite-element program. Parameters were obtained from an oedometer test, and the results were extrapolated over the full soil profile. Various plausible assumptions about the shape of the isotaches around yield were explored, and it is shown that the predicted long-term settlement may vary by a factor of two or more, depending on the assumptions made.
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References
Bjerrum, L. (1967). “Engineering geology of Norwegian normally-consolidated clays as related to settlements of buildings.” Geotechnique, 17(2), 83–118.
Bjerrum, L. (1972). “Embankments on soft ground. State of the art report.” Proc., ASCE Specialty Conf. on Performance of Earth and Earth-Supported Structures, Vol. 2, ASCE, Reston, VA, 1–54.
BRISCON 5.8 [Computer software]. Bristol, U.K., Univ. of Bristol.
Buisman, K. (1936). “Results of long duration settlement tests.” Proc., 1st Int. Conf. on Soil Mechanics and Foundation Engineering, Vol. 1, Geomechanical Engineers, Winchester, MA, 103–107.
Burland, J. B. (1990). “On the compressibility and shear strength of natural clays.” Geotechnique, 40(3), 329–378.
Butterfield, R. (1979). “A natural compression law for soils (an advance on ).” Geotechnique, 29(4), 469–480.
Claesson, P. (2003). “Long term settlements of clays.” Ph.D. thesis, Chalmers Univ. of Technology, Götheborg, Sweden.
Degago, S. A. (2011). “On creep during primary consolidation of clays.” Ph.D. thesis, Norwegian Univ. of Science and Technology, Tondheim, Norway.
Degago, S. A., Grimstad, G., Jostad, H. P., Nordal, S., and Olsson, M. (2011). “Use and misuse of the isotache concept with respect to creep hypotheses A and B.” Geotechnique, 61(10), 897–908.
den Haan, E. J. (1992). “The formulation of virgin compression in soils.” Geotechnique, 42(3), 465–484.
den Haan, E. J. (1996). “A compression model for non-brittle soft clays and peat.” Geotechnique, 46(1), 1–16.
Garlanger, J. E. (1972). “Consolidation of soils exhibiting creep under constant effective stress.” Geotechnique, 22(1), 71–78.
Grimstad, G., Degago, S. A., Nordal, S., and Karstunen, M. (2010). “Modelling creep and rate effects in structured anisotropic soft clays.” Acta Geotech., 5(1), 69–81.
Janbu, N. (1969). “The resistance concept applied to deformations of soils.” Proc., 7th Int. Conf. on Soil Mechanics and Foundation Engineering, Vol. 1, Sociedad Mexicana de Mecanica de Suelos. Mexico City, 191–196.
Jostad, H. P., and Degago, S. A. (2010). “Comparison of methods for calculation of settlements of soft clay.” Numerical methods in geotechnical engineering, T. Benz and S. Nordahl, eds., Taylor and Francis, London, 57–62.
Kabbaj, M., Oka, F., Leroueil, S., and Tavenas, F. (1986). “Consolidation of natural clays and laboratory testing.” Proc., ASTM Symp. on the Consolidation of Soils: Testing and Evaluation, R. N. Yong and F. C. Townsend, eds., ASTM, Philadelphia, 71–103.
Karstunen, M., Krenn, H., Wheeler, S. J., Koskinen, M., and Zentar, R. (2005). “Effect of anisotropy and destructuration on the behavior of Murro test embankment.” Int. J. Geomech., 87–97.
Kim, Y. T., and Leroueil, S. (2001). “Modelling the viscoplastic behavior of clays during consolidation: Application to Berthierville clay in both laboratory and field conditions.” Can. Geotech. J., 38(3), 484–497.
Ladd, C. C., Foott, R., Ishihara, K., Schlosser, F., and Poulos, H. G. (1977). “Stress-deformation and strength characteristics: State-of-the-art report.” Proc., 9th Int. Conf. on Soil Mechanics and Foundation Engineering, Vol. 2, Japanese Geotechnical Society, Tokyo, 421–494.
Leoni, M., Karstunen, M., and Vermeer, P. A. (2008). “Anisotropic creep model for soft soils.” Geotechnique, 58(3), 215–226.
Leroueil, S. (1988). “Tenth Canadian Geotechnical Colloquium. Recent developments in consolidation of natural clays.” Can. Geotech. J., 25(1), 85–107.
Leroueil, S. (2006). “Šuklje Memorial Lecture: The isotache approach. Where are we 50 years after its development by Professor Šuklje?” Proc., 13th Danube-European Conf. on Geotechnical Engineering, Vol. 2, Slovenian Geotechnical Society, Ljubljana, Slovenia, 55–88.
Leroueil, S., and Vaughan, P. R. (1990). “The general and congruent effects of structure in natural soils and weak rocks.” Geotechnique, 40(3), 467–488.
Magnan, J.-P., Baghery, S., Brucy, M., and Tavenas, F. (1979). “Etude numérique de la consolidation unidimensionnelle en tenant compte des variations de la perméabilité et de la compressibilité du sol, du fluage et de la non-saturation.” Bull. Liaison Lab. Ponts Chaussées, 103, 83–94.
Mesri, G., and Choi, Y. K. (1985). “The uniqueness of the end-of-primary (EOP) void ratio-effective stress relationship.” Proc., 11th Int. Conf. on Soil Mechanics and Foundation Engineering, Vol. 2, Balkema, Rotterdam, Netherlands, 587–590.
Nash, D. F. T. (2001). “Modelling the effects of surcharge to reduce long term settlement of reclamations over soft clays: A numerical case study.” Soils Found., 41(5), 1–13.
Nash, D. F. T. (2010). “Influence of destructuration of soft clay on time-dependent settlements.” Numerical methods in geotechnical engineering, T. Benz and S. Nordahl, eds., Taylor and Francis, London, 75–80.
Nash, D. F. T., and Ryde, S. J. (2001). “Modelling the consolidation of compressible soils subject to creep around vertical drains.” Geotechnique, 51(3), 257–273.
Nash, D. F. T., Sills, G. C., and Davison, L. R. (1992). “One-dimensional consolidation testing of soft clay from Bothkennar.” Geotechnique, 42(2), 241–256.
Olsson, M. (2010). “Calculating long-term settlement in soft clays with special focus on the Gothenburg region.” Licentiate thesis, Dept. of Civil and Environmental Engineering, Chalmers Univ., Gothenburg, Sweden.
Plaxis 2D 9 [Computer software]. Delft, Netherlands, Plaxis.
Rouainia, M., and Muir Wood, D. (2000). “A kinematic hardening constitutive model for natural clays with loss of structure.” Geotechnique, 50(2), 153–164.
Šuklje, L. (1957). “The analysis of the consolidation process by the isotache method.” Proc., 4th Int. Conf. on Soil Mechanics and Foundation Engineering, Vol. 1, Butterworths, London, 200–206.
Svanö, G., Christensen, S., and Nordahl, S. (1991). “A soil model for consolidation and creep.” Proc., 10th European Conf. on Soil Mechanics and Foundation Engineering, Vol. 1, Balkema, Rotterdam, Netherlands, 269–272.
Taylor, D. W. (1948). Fundamentals of soil mechanics, Chapman and Hall, London.
Taylor, D. W., and Merchant, W. (1940). “A theory of clay consolidation accounting for secondary compression.” J. Math. Phys., 19(3), 167–185.
Vermeer, P. A., and Neher, H. P. (1999). “A soft soil model that accounts for creep.” Proc., Int. Symp. Beyond 2000 in Computational Geotechnics—10 Years of Plaxis International, Balkema, Rotterdam, Netherlands, 249–261.
Watabe, Y., and Leroueil, S. (2012). “Modeling and implementation of the isotache concept for long-term consolidation behavior.” Int. J. Geomech., (Nov. 8, 2012).
Waterman, D., and Broere, W. (2004). “Plaxis tutorial: Practical application of the soft soil creep model.” Plaxis knowledge base, 〈http://kb.plaxis.nl/publications/practical-application-soft-soil-creep-model〉 (Apr. 4, 2012).
Yildiz, A., Karstunen, M., and Krenn, H. (2009). “Effect of anisotropy and destructuration on behavior of Haarajoki test embankment.” Int. J. Geomech., 153–168.
Yin, J.-H., and Graham, J. (1989). “Viscous-elastic-plastic modelling of one-dimensional time-dependent behaviour.” Can. Geotech. J., 26(2), 199–209.
Yin, J.-H., and Graham, J. (1996). “Elastic visco-plastic modelling of one-dimensional consolidation.” Geotechnique, 46(3), 515–527.
Yin, J.-H., Zhu, J.-G., and Graham, J. (2002). “A new elastic viscoplastic model for time-dependent behaviour of normally and over-consolidated clays: Theory and verification.” Can. Geotech. J., 39(1), 157–173.
Zhou, C., Yin, J.-H., Zhu, J.-G., and Cheng, C.-M. (2005). “Elastic anisotropic viscoplastic modeling of the strain-rate-dependent stress–strain behavior of -consolidated natural marine clays in triaxial shear tests.” Int. J. Geomech., 218–232.
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© 2014 American Society of Civil Engineers.
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Received: Apr 18, 2012
Accepted: Dec 26, 2012
Published online: Jan 4, 2013
Published in print: Oct 1, 2015
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