Soil–environment interactions in geotechnical engineering

Gens, Antonio

doi:10.1680/geot.9.p.109

Cited by 384 publications

(237 citation statements)

References 231 publications

Supporting

Mentioning

198

Contrasting

Unclassified

Order By: Relevance

“…Nevertheless, numerous forensic analyses of geotechnical problems related to slope stability (Griffiths and Lu 2005;Gens 2010;Sorbino and Nicotera 2013), foundations on expansive soils (Attwooll et al 2006), settlement of railway embankments (Cardoso et al 2012) and problems related to geo-environmental engineering and mining engineering have provided some insight on engineering applications of unsaturated soil mechanics. For example, Alonso and Olivella (2006) reported that embankments and dams can experience significant deformations under the influence of seasonal wetting and drying cycles.…”

Section: Final Notementioning

confidence: 99%

Effect of Pore-Water Surface Tension on Tensile Strength of Unsaturated Sand

2016

View full text Add to dashboard Cite

Tensile behaviour of unsaturated sand was investigated both experimentally and theoretically.A custom-built direct tension apparatus was employed to perform direct tension tests on unsaturated silica sand specimens at different saturations levels and packing dry densities.Attempt was made to understand the effect of surface tension of pore-liquid and tensile loading rate on the tensile strength. It was found that the tensile strength decreases, as the surface tension of the pore-liquid decreases and rate of loading increases. However, tensile strength does not decrease as a simple multiple of ratio of surface tension of pore-liquid. The experimental results were also compared with the predicted results from two theoretical tensile strength models, namely, micro-mechanical and the macro-mechanical models. Results predicted using the micro-mechanical model agreed well with the experimental results, but only for specimens containing distilled water in the pendular saturation regime. On the other hand, the macro-mechanical model followed the experimental trend across pendular and funicular saturation regimes for specimens containing distilled water reasonably well.However, at reduced surface tension of pore-liquid, both models significantly under-predicted the experimental tensile strength results.iii ACKNOWLEDGEMENTS Foremost, I would like to express the deepest appreciation to my thesis supervisor and mentor, Dr. Jitendrapal Sharma, who has the attitude and the substance of a genius. Without his guidance and relentless encouragement, my thesis would not have been possible. I would also like to thank him for his financial support throughout the course of the researchwork.Thanks for everything, Dr. Sharma.In addition, a big thank you to my co-supervisor Dr. Rashid Bashir, whose expertise in unsaturated soil mechanics helped me to structure my research and thesis. He has shared valuable insights in the relevance of the study and made this research successful. I would also

show abstract

Section: Final Notementioning

confidence: 99%

Effect of Pore-Water Surface Tension on Tensile Strength of Unsaturated Sand

2016

View full text Add to dashboard Cite

show abstract

“…The main part of their research was focused on a bentonite, yielding large deformations (up to 15% due to a change in pore liquid only). Constitutive models based on these results were proposed by Loret et al (2002), Gajo & Loret (2003), and Gajo et al (2002) under one framework, and by Gens (2010) and Guimarães et al (2007) under a different framework.…”

Section: Theories and Evidencementioning

confidence: 99%

“…In contrast, the latter framework (Gens, 2010;Guimarães et al, 2007) consists of a double-structured model in which the chemical part is represented by osmotic suction. This osmotic suction works at the microscopic level, and all of the strains it produces are considered completely reversible.…”

Section: Theories and Evidencementioning

confidence: 99%

See 1 more Smart Citation

An experimental and constitutive investigation on the chemo-mechanical behaviour of a clay

Witteveen

Ferrari

Laloui³

2013

Géotechnique

View full text Add to dashboard Cite

An experimental and constitutive investigation on the chemo-mechanical behaviour of a clay P. WITTEVEEN Ã , A. F ERRARI Ã a nd L. LALOU I Ã Engineering issues for which the understanding of the chemo-mechanical behaviour of soils is relevant include wellbore stability problems, the salinification of groundwater, and nuclear waste storage. However, despite the vast number of situations in which couplings between chemistry and mechanics occur, the available constitutive models rely on limited experimental evidence. This paper presents the results of an experimental programme on the chemo-mechanical behaviour of a non-swelling illite. The osmotic suction is controlled through the ion concentration of sodium chloride in the pore water. Stress paths include mechanical loading at a constant osmotic suction, and an increasing osmotic suction at a constant mechanical stress. The experimental results point out a correlation between the osmotic suction and initial oedometric modulus, as well as between the osmotic suction and yield stress. A constitutive framework for soils is extended to take the observed chemo-mechanical couplings into account. The numerical model has been calibrated for the illite using the parameters obtained through the tests under mechanical loading at a constant concentration, and validated using more elaborate stress paths. The presented experimental and constitutive investigation builds a basis for the assessment of engineering issues in which pore liquid chemistry plays a major role.

show abstract

“…interventions on near-surface and/or underground deposits for the purpose of environmental remediation (e.g., disposal of CO 2 and hazardous wastes) and risk management (e.g., protection of cities and/or coastal areas from sea level rise and other geohazards). Research on the multi-physics of geological systems, as well as on the couplings between mechanical, hydrologic, chemical and biological agents in the natural environment, is therefore a new frontier to be explored to devise innovative technological solutions able to face the abovementioned challenges [4].…”

Section: Introductionmentioning

confidence: 99%

Modelling suction instabilities in soils at varying degrees of saturation

Buscarnera

Mihalache

2016

E3S Web Conf.

View full text Add to dashboard Cite

Abstract. Wetting paths imparted by the natural environment and/or human activities affect the state of soils in the near-surface, promoting transitions across different regimes of saturation. This paper discusses a set of techniques aimed at quantifying the role of hydrologic processes on the hydro-mechanical stability of soil specimens subjected to saturation events. Emphasis is given to the mechanical conditions leading to coupled flow/deformation instabilities. For this purpose, energy balance arguments for three-phase systems are used to derive second-order work expressions applicable to various regimes of saturation. Controllability analyses are then performed to relate such work input with constitutive singularities that reflect the loss of strength under coupled and/or uncoupled hydro-mechanical forcing. A suction-dependent plastic model is finally used to track the evolution of stability conditions in samples subjected to wetting, thus quantifying the growth of the potential for coupled failure modes upon increasing degree of saturation. These findings are eventually linked with the properties of the field equations that govern pore pressure transients, thus disclosing a conceptual link between the onset of coupled hydro-mechanical failures and the evolution of suction with time. Such results point out that mathematical instabilities caused by a non-linear suction dependent behaviour play an important role in the advanced constitutive and/or numerical tools that are commonly used for the analysis of geomechanical problems in the unsaturated zone, and further stress that the relation between suction transients and soil deformations is a key factor for the interpretation of runaway failures caused by intense saturation events.

show abstract

Soil–environment interactions in geotechnical engineering

Cited by 384 publications

References 231 publications

Effect of Pore-Water Surface Tension on Tensile Strength of Unsaturated Sand

Effect of Pore-Water Surface Tension on Tensile Strength of Unsaturated Sand

An experimental and constitutive investigation on the chemo-mechanical behaviour of a clay

Modelling suction instabilities in soils at varying degrees of saturation

Contact Info

Product

Resources

About