اثر فرآیند یخبندان و ذوب بر تراکم پذیری خاک

نوع مقاله: مقاله پژوهشی

نویسندگان

1 گروه آموزشی مهندسی بیوسیستم، پردیس کشاورزی و منابع طبیعی، دانشگاه تهران

2 گروه آموزشی مهندسی علوم خاک، پردیس کشاورزی و منابع طبیعی، داشگاه تهران

چکیده

چکیده
یکی از فرآیندهای مؤثر بر ساختمان خاک، فرآیند یخبندان و ذوب است. فرآیند یخبندان و ذوب بر تراکم‌پذیری خاک تأثیر گذاشته و آستانه تراکم‌پذیری (ﻇﺮﻓﻴﺖ ﺑﺎرﺑﺮی ﻳﺎ ﺗﻨﺶ ﭘﻴﺶ­ﺗﺮاﻛﻤﻲ) را تغییر می­دهد. به­همین منظور اثر این فرآیند بر ظرفیت باربری خاک و همچنین میزان انرژی مصرفی در حین تراکم خاک مورد مطالعه قرار گرفت. در این پژوهش نمونه­های خاک با حجم 4400 سانتی­متر مکعب در دو سطح رطوبتی 10 و 15 درصد با سه چگالی ظاهری 15/1 و 265/1 و 39/1 گرم بر سانتی‌متر‌مکعب تهیه و تحت تأثیر فرآیند یخبندان و ذوب قرار گرفتند و نتایج با نمونه­های مشابه ولی بدون تأثیر فرآیند یخبندان و ذوب (تیمار شاهد) مقایسه شدند. نتایج نشان دادند که فرآیند یخبندان و ذوب تأثیر معنی­داری بر ظرفیت باربری و انرژی مورد نیاز جهت تراکم خاک داشته و باعث کاهش هر دو کمیت شد. هر چند این فرآیند ساختمان خاک را بهبود بخشیده و آن را اصلاح می­نماید ولی اعمال هر بار فشاری بیش‌ از تنش پیش‌تراکمی، علاوه بر از بین بردن اثرات مفید یخبندان و ذوب بر ساختمان خاک، باعث تراکم بیشتر خاک نیز می‌شود. لذا به‌کارگیری ادوات و ماشین­ها در مزرعه باید با دقت و متناسب با شرایط فیزیکی خاک با توجه به عوامل تأثیرگذار بر آن باشد.

کلیدواژه‌ها


Alakukku L. 1996. Persistence of soil compaction due to high axle load traffic. I. Short-term effects on the properties of clay and organic soils. Soil and Tillage Research. 37: 211-222.
Alexandrou A and Earl R. 1995. In situ determination of the pre-compaction stress of a soil. Journal of Agricultural Engineering Research. 61: 67-71.
Andersland O. B. and Ladanyi B. 2004. Frozen ground engineering. John Wiley & Sons.
Aragón A., Garcıa M., Filgueira R. and Pachepsky Y. A. 2000. Maximum compactibility of Argentine soils from the Proctor test; the relationship with organic carbon and water content. Soil and Tillage Research. 56: 197-204.
Aura E. 1983. Soil compaction by the tractor in spring and its effect on soil porosity [Finland]. Journal of the scientific agricultural society of Finland.
Canarache A. Horn R. and Colibas I. 2000. Compressibility of soils in a long term field experiment with intensive deep ripping in Romania. Soil and Tillage Research. 56: 185-196.
Cavalieri K.M.V. Arvidsson J. da, Silva A. P and Keller T. 2008. Determination of precompression stress from uniaxial compression tests. Soil and Tillage Research. 98: 17-26.
Collins I. F. 2005. The concept of stored plastic work or frozen elastic energy in soil mechanics. Geotechnique. 55: 373-382.
Cui Z. D. He P. P and Yang W. H. 2014. Mechanical properties of a silty clay subjected to freezing–thawing. Cold Regions Science and Technology. 98: 26-34.
Culley J. 1993. Density and compressibility. Soil sampling and methods of analysis. 1: 529-539.
Dash J. G. 1989. Thermonuclear pressure in surface melting. Motivation for frost heave science. 246: 1591-1593.
Eigenbrod K. 1996. Effects of cyclic freezing and thawing on volume changes and permeabilities of soft fine-gained soils. Canadian Geotechnical Journal. 33: 529-537.
Ghazviani M and Roustaei M. 2013. Freeze–thaw performance of clayey soil reinforced with geotextile layer. Cold Regions Science and Technology. 89: 22-29.
Graham J. and Au V. 1985. Effects of freeze-thaw and softening on natural clay at low stresses. Canadian Geotechnical Journal. 22: 69-78.
Hamza M. and Anderson W. 2005. Soil compaction in cropping systems: A review of the nature, causes and possible solutions. Soil and tillage research. 82: 121-145.
Jabro J. D., Iversen W. M., Evans R. G., Allen B. L. and Stevens W. B. 2014. Repeated Freeze-Thaw Cycle Effects on Soil Compaction in a Clay Loam in Northeastern Montana. Soil Science Society of America Journal 78, 737.
Keller T and Arvidsson J. 2007. Compressive properties of some Swedish and Danish structured agricultural soils measured in uniaxial compression tests. European journal of soil science. 58: 1373-1381.
Konrad J. M. 1989. Physical processes during freeze-thaw cycles in clayey silts. Cold Regions Science and Technology. 16: 291-303.
Mosaddeghi M. R. 2003. Pre-compaction stress and relationship with the physical and mechanical properties of selected soil in isfahan. College of agriculture. Isfahan univessity of technology, Isfahan, P. 245.
Mosaddeghi M. R.,  Hemmat A., Hajabbasi M. A., Vafaeian M. and Alexandrou A. 2006. Plate sinkage versus confined compression tests for in situ soil compressibility studies. Biosystems Engineering. 93: 325-334.
Oldeman L., Hakkeling R. and Sombroek W. 1991. World map of the status of human-induced soil degradation: an explanatory note, 2nd. Rev. ISRIC [etc.].
Qi J., Ma W. and Song C. 2008. Influence of freeze–thaw on engineering properties of a silty soil. Cold regions science and technology. 53: 397-404.
Qi J., Z. Zhang and Zhu J. Y. 2003. Influence of freezing-thawing on soil structure and its soil mechanics significance. Chinese Journal of Rock Mechanics and Engineering. 22: 2690-2694.
QIN L. M., CHI S. C. and LIN G. 2005. A Model of soil constitutive relation based on energy dissipation its parameters determination. Chinese Journal of Rock Mechanics and Engineering. S2. 
Raghavan G., Alvo P. and McKyes E. 1990. Soil compaction in agriculture: a view toward managing the problem. Advances in soil science. Springer, pp. 1-36.
Römkens M. and Miller R.. 1971. Predictingroot size and frequency from one-dimensional consolidation data—a mathematical model. Plant and soil. 35: 237-248.
Rücknagel J., Brandhuber R., Hofmann B., Lebert M., Marschall K., Paul R., Stock O. and Christen O. 2010.Variance of mechanical precompression stress in graphic estimations using the Casagrande method and derived mathematical models. Soil and Tillage Research. 106: 165-170.
Schafer R., Johnson C., Koolen A., Gupta S. and Horn R. 1992. Future research needs in soil compaction. Transactions of the ASAE. 35: 1761-1770.
Shainberg I., Keren R. and Frenkel H. 1982. Response of sodic soils to gypsum and calcium chloride application. Soil Science Society of America Journal. 46: 113-117.
Soane B. D. 1985. Traction and transport systems as related to cropping systems. Journal of Terramechanics. 22: 184.
Tahmasebi M., Hemmat A., Vafaiee M.. and Mosaddeghi M. R. 2006. Application of Stress tests in determining the pre-compression stress of a sandy-loam soil and its relationship with shear strength. Seventh International Congress on Civil Engineering.
Wang D. -y., Ma W., Niu Y.-h., Chang X.-x. and Wen Z. 2007. Effects of cyclic freezing and thawing on mechanical properties of Qinghai–Tibet clay. Cold regions science and technology. 48: 34-43.
Watts C., Hallett P. and Dexter A. 1999. Effects of mechanical stresses and strains on soil respiration. Effect of Mineral-Organic-Microorganism Interactions on Soil and Freshwater Environments. Springer, pp. 305-316.
Williams P. J. and Perfect E. 1980. Investigation of thermally actuated water migration in frozen soils. Energy, Mines and Resources Canada, Earth Physics Branch.
Yao X., Qi J. and Ma W. 2009. Influence of freeze–thaw on the stored free energy in soils. Cold Regions Science and Technology 56.