KİL ZEMİNLERİN MEKANİK DAVRANIŞINA TUZ ÇÖZELTİLERİ ETKİSİ

Kil zeminlerin kohezif karakterli olması ve su tutma davranışının non-plastik zeminlere kıyasla farklı mekanizmalarla işliyor olması nedeniyle yük altındaki mekanik davranışı da farklı mekanizmalarla açıklanmaktadır. Non-plastik zeminlerden farklı olarak killerin sıkışma, makaslama kuvvetlerine dayanma, su tutma gibi mekanik davranışında elektriksel ve moleküler kuvvetler etkindir. Kil daneleri arasındaki etkileşime etki eden kuvvetler üzerinde değişime yol açabilecek tüm dış etkiler kilin mekanik davranışna da etki etmektedir. Dolayısıyla killerin mekanik davranışları boşluk suyu kompozisyonundan etkilenmektedir. Kohezif zeminlerin su tutma davranışını etkileyen ortam sıcaklığı, pH, boşluk suyunun yalıtkanlık sabiti (dielectric constant – DC), iyon konsantrasyonu (çözünmüş tuz miktarı) gibi etkenler aynı zamanda mekanik davranışına da etki etmektedir. Yazı kapsamında kil zeminlerin mekanik davranışına etkiyen bu etkenlerden sadece boşluk suyundaki tuz yoğunluğunun etkisi incelenecektir. Bu amaçla öncelikle başucu niteliğindeki kitaplardan yola çıkarak kil-tuz etkileşimin temel mekanizması ana hatlarıyla açıklanmaya çalışılmıştır. Sonrasında yakın dönemde yapılmış güncel yayınlardaki bulgularlar, kil – kimyasal etkileşiminin temel mekanizmalarıyla irdelenerek etkileşimin genelden özele izahına çalışılmıştır.

Effect of Salt Solutions on the Mechanical Behavior of Clay Soils

The mechanical behavior of clay soils under load is also explained by different mechanisms, since they have a cohesive character and their water retention behavior works by different mechanisms compared to non-plastic soils. Unlike non-plastic soils, electrical and molecular forces are effective in the mechanical behavior of clays such as compression, resistance to shear forces, and water retention. All external effects that may cause a change on the forces acting on the interaction between clay particles also affect the mechanical behavior of the clay. The mechanical behavior of clays is affected by the pore water composition. Factors such as ambient temperature, pH, dielectric constant of pore water (dielectric constant – DC), ion concentration (amount of dissolved salt) that affect the water holding behavior of cohesive soils also affect their mechanical behavior. Within the scope of the article, only the effect of salt concentration in the pore water will be examined among these factors affecting the mechanical behavior of clay soils. For this purpose, the basic mechanism of clay-salt interaction has been tried to be explained with the main lines, starting from the books that have the quality of a bedside book. Afterwards, the findings in recent publications were examined with the basic mechanisms of the clay-chemical interaction, and the interaction was tried to be explained from general to specific.

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  • Mitchell JK, Soga K. Fundamentals of soil Behavior. John Wiley& Sons, Hoboken, New Jersey, USA. 2005.
  • Sridharan A. Engineering behaviour of fine grained soils—a fundamental approach. Indian Geotechnical Journal. 1991;21:1–136.
  • Man A, Graham J. Pore fluid chemistry, stress-strain behaviour, and yielding in reconstituted highly plastic clay. Eng Geol [Internet]. 2010;116:296–310. Available from: internal-pdf://183.103.134.107/Pore-fluid-chemistry-stress-strain-behaviour-a.pdf.
  • Gratchev I, Towhata I. Stress–strain characteristics of two natural soils subjected to long-term acidic contamination. Soils and Foundations [Internet]. 2013;53:469–76. Available from: internal-pdf://64.89.60.125/Stress–strain characteristics of two natural s.pdf.
  • Sridharan A, Prakash K. Influence of clay mineralogy and pore-medium chemistry on clay sediment formation. Canadian Geotechnical Journal. 1999;36:961–6.
  • Di Maio C. Influence of Pore Fluid Composition on Volume Change Behaviour of Clays Exposed to the Same Fluid as the Pore Fluid. In: Loret B, Huyghe JM, editors. Chemo-Mechanical Couplings in Porous Media Geomechanics and Biomechanics [Internet]. Vienna: Springer Vienna; 2004. p. 1–17. Available from: https://doi.org/10.1007/978-3-7091-2778-0_1.
  • Pontolillo DM, De Rosa J, Scaringi G, Di Maio C. Clay Creep and Displacements: Influence of Pore Fluid Composition. Procedia Eng. 2016. p. 69–74.
  • Jang J, Cao SC, Stern LA, Jung J, Waite WF. Impact of Pore Fluid Chemistry on Fine‐Grained Sediment Fabric and Compressibility. J Geophys Res Solid Earth. 2018;123:5495–514.
  • Prakash K, Sridharan A. Determination of liquid limit from equilibrium sediment volume. Geotechnique [Internet]. 2002;52:693–6. Available from: internal-pdf://159.36.159.28/Determination of liquid limit from equilibrium.pdf.
  • Jiang N, Wang C, Wu Q, Li S. Influence of structure and liquid limit on the secondary compressibility of soft soils. J Mar Sci Eng. 2020;8:627.
  • Schmitz RM, Schroeder C, Charlier R. Chemo–mechanical interactions in clay: a correlation between clay mineralogy and Atterberg limits. Appl Clay Sci [Internet]. 2004;26:351–8. Available from: internal-pdf://189.24.94.64/Schmitz-2004-Chemo–mechanical interactions in.pdf internal-pdf://4004932370/Schmitz-2004-Chemo–mechanical interactions in1.pdf.
  • Jang J, Carlos Santamarina J. Fines Classification Based on Sensitivity to Pore-Fluid Chemistry. Journal of Geotechnical and Geoenvironmental Engineering [Internet]. 2016;142:6015018. Available from: internal-pdf://120.246.130.252/Fines Classification Based on Sensitivity to P.pdf.
  • Ghosh P. Chemical Engineering - Interfacial Engineering [Internet]. Intermolecular and Surface Forces. Indian Institutes of Technology-Department of Chemical Engineering : NPTEL ; 2012 [cited 2018 Oct 12]. Available from: http://nptel.ac.in/courses/103103033/.
  • Holtz RD, Kovacs WD, Sheahan TC. An introduction to geotechnical engineering. 2nd ed. Prentice-Hall Englewood Cliffs; 1981.
  • Koper GJM. An Introduction to Interfacial Engineering. VSSD Delft; 2007.
  • Holtz RD, Kovacs WD, Sheahan TC. An introduction to geotechnical engineering. 2011.
  • Di Maio C. Exposure of bentonite to salt solution: Osmotic and mechanical effects. Geotechnique. 1996;46:695–707.
  • Horan AJ. The Mechanical Behavior Of Normally Consolidated Soils As A Function Of Pore Fluid Salinity [Internet]. Civil and Environmental Engineering. 2015. Available from: internal-pdf://66.165.152.48/The mechanical behavior of normally consolidat.pdf.
  • Horpibulsuk S, Yangsukkaseam N, Chinkulkijniwat A, Du YJ. Compressibility and permeability of Bangkok clay compared with kaolinite and bentonite. Appl Clay Sci. 2011;52:150–9.
  • Naeini M. A., Jahanfar S. A. Effect of Salt Solution and Plasticity Index on undrain Shear Strength of Clays. International Journal of Chemical, Molecular, Nuclear, Materials and Metallurgical Engineering [Internet]. 2011;5:92–6. Available from: internal-pdf://67.227.106.255/Effect of Salt Solution and Plasticity Index o.pdf.
  • Sridharan A. Engineering behaviour of fine grained soils—a fundamental approach. Indian Geotechnical Journal: Thirteenth IGS Annual Lecture delivered on the occasion of its 32nd Annual General Session [Internet]. 1991 [cited 2023 Mar 7];447–540. Available from: http://www.iitg.ac.in/amurali/IGJ/IGS%20Annual%20Lectures/1990%20Prof.%20A.%20Sridharan%20-%20IGS%20Annual%20Lecture.PDF.
  • Calvello M, Lasco M, Vassallo R, Di Maio C. Compressibility and residual shear strength of smectitic clays: influence of pore aqueous solutions and organic solvents. Italian Geotechnical Journal [Internet]. 2005 [cited 2023 Mar 7];1:34–46. Available from: https://associazionegeotecnica.it/wp-content/uploads/2010/03/RIG_2005_1_034.pdf.
  • Song MM, Zeng LL, Hong ZS. Pore fluid salinity effects on physicochemical-compressive behaviour of reconstituted marine clays. Appl Clay Sci. 2017;146:270–7.
  • Dor M, Levi-Kalisman Y, Day-Stirrat R, Mishael Y, Emmanuel S. Assembly of Clay Mineral Platelets, Tactoids, and Aggregates: Effect of Mineral Structure and Solution Salinity. J Colloid Interface Sci. 2020;566.
  • Calvello M, Lasco M, Vassallo R, di Maio C. Compressibility and residual shear strength of smectitic clays: influence of pore aqueous solutions and organic solvents. 2005; Available from: internal-pdf://248.141.175.146/Compressibility and residual shear strength of.pdf.
  • Rao SM, Sridharan A, Chandrakaran S. Influence of Drying on the Liquid Limit Behavior of a Marine Clay. Geotechnique. 1989;39:715–9.
  • Varank G, Demir A, GÜVENÇ SY, ÖZÇOBAN MŞ. Effect of inorganic salt solutions on consistency limits of kaolinite. Balıkesir Üniversitesi Fen Bilimleri Enstitüsü Dergisi. 2018;20:110–20.
  • Arasan S, Yetimoğlu T. Effect of Inorganic Salt Solutions on the Consistency Limits of Two Clays. Turkish J Eng Env Sci [Internet]. 2008;32 (2008):107 – 115. Available from: internal-pdf://248.105.97.247/Effect of Inorganic Salt Solutions on the Cons.pdf.
  • Scaringi G. Influence Of Pore Fluid Composition On Clay Behaviour And Chemo-Mechanical Study Of A Clayey Landslide [Internet]. Rischio Sismico, Ingegneria Strutturale e Geotecnica. 2015. Available from: internal-pdf://245.78.127.58/INFLUENCE OF PORE FLUID COMPOSITIONIN FLUENCE.pdf.
  • Park J, Vipulanandan C, Kim JW, Oh MH. Effects of surfactants and electrolyte solutions on the properties of soil. Environmental Geology. 2006;49:977–89.
  • Nguyen XP, Cui YJ, Tang AM, Deng YF, Li XL, Wouters L. Effects of pore water chemical composition on the hydro-mechanical behavior of natural stiff clays. Eng Geol. 2013;166:52–64.
  • Dutta J, Mishra AK. Consolidation behaviour of bentonites in the presence of salt solutions. Appl Clay Sci. 2016;120:61–9.
  • Wu Z, Deng Y, Cui Y, Zhou A, Feng Q, Xue H. Experimental Study on Creep Behavior in Oedometer Tests of Reconstituted Soft Clays. International Journal of Geomechanics. 2019;19.
  • Deng YF, Cui YJ, Tang AM, Li XL, Sillen X. An experimental study on the secondary deformation of Boom clay. Appl Clay Sci. 2012;59–60:19–25.
  • Miao L, Kavazanjian E. Secondary compression features of Jiangsu soft marine clay. Marine Georesources and Geotechnology [Internet]. 2007;25:129–44. Available from: https://doi.org/10.1080/10641190701380258.
  • Di Maio C, Santoli L, Schiavone P. Volume change behaviour of clays: The influence of mineral composition, pore fluid composition and stress state. Mechanics of Materials. 2004;36:435–51.
  • Mesri G, Castro A. Cα/Cc concept and K0 during secondary compression. Journal of Geotechnical Engineering. 1987;113:230–47.