بررسی رفتار برشی ماسه کربناته جزیره خارک در حالت سیمانی سازی شده به صورت شبه طبیعی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 گروه مهندسی عمران، دانشکده مهندسی، دانشگاه فسا، فسا، ایران

2 گروه مهندسی عمران، دانشکده مهندسی، دانشگاه فسا، فسا، ایران.

چکیده

در این پژوهش به بررسی تاثیر سیمانی شدن طبیعی بر رفتار برشی ماسه­ کربناته جزیره خارک پرداخته شده است. بدین منظور از یک روش شبیه سازی سیمانی شدن خاک در طبیعت برای سیمانی سازی کردن نمونه­های این خاک استفاده گردید. اهمیت این روش سیمانی سازی در قابلیت آن به ‌عنوان جایگزینی برای نمونه‌های دست نخورده سیمانی شده طبیعی است که در عمل به دست آوردن آن‌ها سخت و پر هزینه است. نمونه­های سیمانی سازی شده با این روش و نمونه‌های غیر سیمانی با استفاده از آزمایش برش مستقیم تحت برش قرار گرفته و نتایج با هم مقایسه و تحلیل گردیدند. همچنین تاثیر متغیرهای مدت زمان عمل­آوری ماسه سیمانی شده و درصد تراکم بر رفتار برشی ماسه­ این محل بررسی شد. مشاهده گردید که سیمانی کردن ماسه خارک باعث افزایش مقاومت به ویژه در تنش‌های قائم بزرگ‌تر و همچنین کاهش تمایل به اتساع گردید. سیمانی کردن خاک باعث افزایش زاویه اصطکاک داخلی گردید در حالی که مشاهده گردید که با سیمانی شدن، چسبندگی خاک میتواند افزایش یا کاهش یاید و یا بدون تغییر بماند. افزایش زمان عمل آوری خاک سیمانی شده خارک همواره باعث افزایش قابل توجه چسبندگی و تغییر ناچیز در زاویه اصطکاک داخلی آن گردید. همچنین مشاهده گردید که افزایش تراکم خاک سیمانی شده خارک می‌تواند منجر به کاهش، افزایش و یا بدون تغییر ماندن چسبندگی آن شود در حالی که عمدتاً باعث افزایش زاویه اصطکاک داخلی آن می‌گردد. عوامل محتمل در ایجاد تغییرات یاد شده معرفی شده و تاثیر هر یک از آن‎ها بررسی گردید.

کلیدواژه‌ها

موضوعات

عنوان مقاله [English]

Shearing behavior of Carbonate Sand of Khark Island Cemented by a Pseudo-natural Method

نویسندگان [English]

  • Mohammad Reza Arvin 1
  • Ali Masoomi 2
  • Mohsen Ajdari 2
1 Civil Engineering Department, Faculty of Engineering, Fasa University, Fasa, Iran.
2 Civil Engineering Department, Fasa University
چکیده [English]

In the present study, the effect of natural cementation on the shearing behavior of carbonate sand of Khark Island, south of Iran, has been investigated. To do so, a pseudo-natural cementation method was employed. The importance of this technique lies in its suitability as a substitute for undisturbed samples of cemented carbonate soil that are hard and costly to prepare. Uncemented and cemented samples provided by this method were tested using direct shear apparatus and the results were analyzed and compared to one another. Furthermore, the effects of factors such as curing time and relative compaction on the shearing behavior of the Khark sand were studied. It was observed that cementation results in the rise of the shearing resistance, in particular at high vertical stresses, and leads to a decline in the tendency of soil to dilation. While cementation led to growth in the internal friction angle of soil, it may cause an increase, a decrease, or no change in the cohesion of the Khark sand.  The increase in curing time led to a considerable rise in the cohesion and a minor change in the internal friction angle of the cemented soil. Furthermore, results showed that as the relative compaction of the investigated cemented carbonate soil goes up, the cohesion of the soil might increase, decline, or stay unchanged while the internal friction angle always increases. Factors that are likely to contribute to the development of the behavior stated earlier were introduced and their effects were discussed thoroughly.

کلیدواژه‌ها [English]

  • Carbonate sand
  • Pseudo-static cementation
  • Direct shear test
  • Shear strength
  • Khark Island

مراجع

[1] B.T. Morioka,  Evaluation of the static and cyclic strength properties of calcareous sand using cone penetrometer tests. PhD Thesis, University of  Hawaii, (1999).   
[2] H.G. Brandes, Simple shear behavior of calcareous and quartz sands, Geotechnical and Geological Engineering, 29 (1) (2011) 113-126 .
[3] N.F. Ismael, A.H.N. Ahmad, Bearing capacity of footings on calcareous sands, Soils and Foundations, 30 (3) (1990) 81-90.
[4] B.W. Byrne,  G. T. Houlsby. Observations of footing behaviour on loose carbonate sands, Géotechnique, 51(5) (2001) 463-466.
[5] S. Ohno, H. Ochiai, N. Yasufuku, Estimation of pile settlement in calcareous sans, Engineering for Calcareous Sediments, Baklkema, Rotterdam, (1999) 1-6.
[6] J.L. Alba,  J. M. Audibert. Pile design in calcareous and carbonaceous granular materials, and historic review, In The 2nd International Conference on Engineering for Calcareous Sediments, (1999) 29-44.
[7] S.M. Safinus, S. Hossain, M.F. Randolph, Comparison of stress-strain behaviour of carbonate and silicate sediments, In Proceedings of the 18th international conference on soil mechanics and geotechnical engineering, Paris, (2013) 267-270.
[8] X.Z. Wang, X. Wang, Z.C. Jin, Q.S. Meng, C.Q. Zhu, R. Wang, Shear characteristics of calcareous gravelly soil, Bulletin of Engineering Geology and the Environment, 76 (2)  (2017) 561-573.
[9] G. Shang, L. Sun, S. Li, X. Liu, W. Chen, Experimental study of the shear strength of carbonate gravel, Bulletin of Engineering Geology and the Environment, (2020) 1-4.
[10] M.R.Coop, K.K. Sorensen, T. Bodas Freitas, G. Georgoutsos, Particle breakage during shearing of a carbonate sand, Géotechnique, 54 (3) (2004) 157-163.
[11] M. Hasanlourad, H. Salehzadeh, H. Shahnazari, Dilation and particle breakage effects on the shear strength of calcareous sands based on energy aspects, International Journal of Civil Engineerng, 6 (2) (2008) 108-119.
[12] H.F. Aghajani, H. Salehzadeh, Anisotropic behavior of the Bushehr carbonate sand in the Persian Gulf, Arabian Journal of Geosciences, 8 (10) (2015) 8197-8217.
[13] X.X. Wang, X. Wang, J.W. Chen, R. Wang, M.J. Hu, Q.S. Meng, Experimental study on permeability characteristics of calcareous soil. Bulletin of Engineering Geology and the Environment, 77 (4) (2018) 1753-1762.
[14] H. Wei, T.  Zhao, J. He, Q. Meng, X. Wang, Evolution of particle breakage for calcareous sands during ring shear tests, International Journal of Geomechanics, 18(2) (2018) 04017153.
[15] X. Zhang, W. Hu, G. Scaringi, B.A. Baudet, W. Han, Particle shape factors and fractal dimension after large shear strains in carbonate sand, Géotechnique Letters, 8(1) (2018) 73-79.
[16] S. Havaee, M. R. Mosaddeghi, S. Ayoubi, In situ surface shear strength as affected by soil characteristics and land use in calcareous soils of central Iran, Geoderma 237 (2015) 137-148.
[17] H. Shahnazari, Y. Jafarian, M.A. Tutunchia R. Rezvani, Undrained cyclic and monotonic behavior of Hormuz calcareous sand using hollow cylinder simple shear tests, International Journal of Civil Engineering, 14(4) (2016) 209-219.
[18] D. Bruce, M. Bruce, The practitioner’s guide to deep mixing. Grouting and ground treatment, In: Proceedings of the third international conference, geotechnical special publication, 120. Edited by American Society of Civil Engineers, (2003) 475–488.
[19] N. Molenaar, A.A.M. Venmans, Calcium carbonate cementation of sand: a method for producing artificially cemented samples for geotechnical testing and a comparison with natural cementation processes, Engineering Geology, 35 (1-2), (1993) 103-122.
 [20] P.V. Lade, D.D. Overton, Cementation effects in frictional materials. Journal of Geotechnical Engineering, 115 (10) (1989) 1373-1387.
[21] A.M. Ajorloo, H. Mroueh, L. Lancelot, Experimental investigation of cement treated sand behavior under triaxial test, Geotechnical and Geological Engineering, 30 (1) (2012) 129-143.
[22] E. Kucharski, G. Price, H.  Li, H.A. Joer, Laboratory evaluation of CIPS cemented calcareous and silica sands. In 7th Australia New Zealand Conference on Geomechanics: Geomechanics in a Changing World: Conference Proceedings (p. 102). Institution of Engineers, Australia, (1996).
[23] M.A. Ismail, H.A. Joer, H.W. Sim, M.F. Randolph, Effect of cement type on shear behavior of cemented calcareous soil, Journal of Geotechnical and Geoenvironmental Engineering, 128 (6) (2002) 520-529.
[24] J.T. Huang, D.W. Airey, Properties of artificially cemented carbonate sand, Journal of Geotechnical and Geoenvironmental Engineering, 124 (6) (1998) 492-499.
[25] P. Xiao, H. Liu, A.W. Stuedlein, T.M. Evans, Y. Xiao, Effect of relative density and biocementation on cyclic response of calcareous sand. Canadian Geotechnical Journal, 56(12) (2019) 1849-1862.
[26] K. Grine, A. Attar, A. Aoubed, D. Breysse,Using the design of experiment to model the effect of silica sand and cement on crushing properties of carbonate sand, Materials and structures, 44 (1) (2011) 195-203.
[27] M. Hassanlourad, H. Salehzadeh, H. Shahnazari, Undrained triaxial shear behavior of grouted carbonate sands, International Journal of Civil Engineering, 9 (4) (2011) 307-314.
[28] R.C. Chaney, S.M. Slonim, S.S. Slonim, Determination of calcium carbonate content in soils, Geotechnical properties, behavior, and performance of calcareous soils. ASTM International, (1982).
[29] J.Q. Shang, E. Mohamedelhassan, M. Ismail, Electrochemical cementation of offshore calcareous soil, Canadian Geotechnical Journal, 41(5) (2004) 877-893.
نشریه مهندسی عمران امیرکبیر
دوره 53، شماره 6
شهریور 1400
صفحه 2415-2434

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