Narlı Kumunun Üç Eksenli Kayma Davranışı

Öz

Bu çalışmada, Güneydoğu Anadolu Bölgesi’nin batısındaki altyapı inşaat faaliyetlerinde sıklıkla kullanılan Narlı Kumuna ait kayma davranışını araştırmak için yapılan üç eksenli basınç deneyi sonuçları sunulmaktadır. Üç farklı efektif gerilme (50 kPa, 100 kPa, ve 150 kPa) ve iki farklı konsolidasyon süresinin (3 saat, ve 18 saat) kayma davranışına etkisi konsolidasyonlu-drenajlı (CD) ve konsolidasyonludrenajsız (CU) deneylerle araştırılmıştır. Çalışmada, Narlı Kumuna ait üç farklı rölatif sıkılıktaki (gevşek, orta sıkı, sıkı) kayma davranışı da sunulmaktadır. Araştırmacılar ve arazide çalışan mühendislerin kullanımı için sunulan deney sonuçları, Narlı Kumuna ait kayma mukavemeti ve rijitlik değerlerinin efektif gerilme, konsolidasyon süresi, ve rölatif sıkılık değerlerindeki artışa bağlı olarak arttığını göstermiştir. Ayrıca, CD şartları altında test edilen örneklere ait deviatörik gerilme, rijitlik, ve içsel sürtünme açısı değerlerinin CU şartlarında test edilen aynı numunelere göre daha yüksek olduğu gözlemlenmiştir.

Anahtar Kelimeler

• Narlı kumu,Üç eksenli test,Rölatif sıkılık,Konsolidasyon süresi

Triaxial Shear Behavior of Narlı Sand

Öz

This study presents an intensive series of conventional triaxial compression tests conducted to investigate the shear behavior of Narli sand, which is a widely consumed geomaterial in earthwork projects in the southern central of Turkey. The effect of three different effective confining pressures (50 kPa, 100 kPa, and 150 kPa) and two consolidation periods (3 hrs, 18 hrs) were investigated during the both consolidated drained (CD) and consolidated undrained (CU) tests. The study also presents the effect of different relative densities (loose, medium, and dense state of the sand) to the shear response of Narli sand. Test results, which are presented for further use by researchers and engineers in practice, indicated that the shear strength and stiffness of Narli sand increase as the effective confining pressure, consolidation period, and the relative density values increase. Further, Narli sand tested in the CD condition exhibits deviatoric stress, stiffness, angle of internal friction values higher than their values observed in the CU condition.

Anahtar Kelimeler

• Narli sand,Triaxial test,Relative density,Consolidation period

Kaynakça

1. 1. Coulomb, C.A., 1776. Essai Sur une Application des Regles des Maximis et Minimis a Quelques Problemes des Statique Relatifs a L’Architecture, Mem. Acad. R. Pres. Divers Savants, 7, Paris.
2. 2. Lee K.L., Seed H.D., 1967. Drained Characteristics of Sand, Journal of the Soil Mech. and Found. Div., ASCE, 93(SM6).
3. 3. Ahmed, S.N.U., 1972. A Study of the Influence of Confining Pressure on the Behavior of Sands, PhD Thesis, McGill university, Montreal, P.Q.
4. 4. Kramer, S.L., Seed, H.B., 1988. Initiation of Soil Liquefaction under Static Loading Conditions, Journal of Geotechnical Engineering, 114(4), 412-430.
5. 5. Cuccovillo, T., Coop, M.R., 1997. The Measurement of Local Axial Strains in Triaxial Tests using LVDTs, Géotechnique, 47(1).
6. 6. Della, N., Arab, A., Belkhatir, M., 2001. Effect of Confining Pressure and Depositional Method on the Undrained Shearing Response of Medium Dense Sand, Journal of Iberian Geology, 37(1), 37-44.
7. 7. Sayeed, A.M., Suzuki, K., Rahman, M.M., 2011. Strength and Deformation Characteristics of Granular Materials under Extremely Low to High Confining Pressures in Triaxial Compression, International Journal of Civil and Environmental Engineering, 11(4), 1-6.
8. 8. Clayton, C.R.I., Heymann, G., 2001. Stiffness of Geomaterials at Very Small Strains, Géotechnique, 51(3), 245-255.

9. 9. Tsomokos, A., Georgiannou, V.N., 2010. Effect of Grain Shape and Angularity on the Undrained Response of Fine Sands, Canadian Geotechnical Journal, 47(5), 539-551.
10. 10. Shahnazari, H., Salehzadeh, H., Rezvani, R., 2014. The Effect of Shape and Stiffness of Originally Different Marine Soil Grains on Their Contractive and Dilative Beaviour, KSCE Journal of Civil Engineering, 18(4), 975-983.
11. 11. Bayat, E., Bayat, M., 2013. Effect of Grading Characteristics on the Undrained Shear Strength of Sand: Review with New Evidences, Arabian Journal of Geosciences, 6 (11), 4409-4418.
12. 12. Belkhatir, M., Schanz, T., Arab, A., 2013. Effect of Fines Content and Void Ratio on the Saturated Hydraulic Conductivity and Undrained Shear Strength of Sand-Silt Mixtures, Environmental Earth Sciences, 70 (6), 2469-2479.
13. 13. Belkhatir, M., Schanz, T., Arab, A., 2014. Insight into the Effects of Gradation on the Pore Pressure Generation of Sand-Silt Mixtures, Geotechnical Testing Journal, 37(5), 922-931.
14. 14. Porovic, E., Jardine, R.J., 1994. Some Observations on the Static and Dynamic Shear Stiffness of Ham River Sand. In Proceedings of the international symposium on Pre-failure Deformation Characteristics of Geomaterials, Sapporo, 25-30.
15. 15. Viggiani, G., Atkinson, J.H., 1995. Stiffness of Fine-Grained Soil at Very Small Strains, Géotechnique, 45(2), 249-265.
16. 16. Maeda, K., Miura, K., 1999. Relative Density Dependency of Mechanical Properties of Sands. Soils and Foundations, 39(1), 69-79.
17. 17. Kokusho T., Hara T., Hiraoka R., 2004. Undrained Shear Strength of Granular Soils with Different Particle Gradations, Journal of Geotechnical and Geoenvironmental Engineering, 130(6), 621-629.
18. 18. Della N., Belkhatir M., Arab A., 2015. Undrained Monotonic Response and Instability of Medium-Dense Sandy Soil, Marine Geosources & Geotechnology, 33 (6), 487-495.
19. 19. Thevanayagam, S., 1998. Effect of Fines and Confining Stress on Undrained Shear Strength of Silty Sands, Journal of Geotechnical and Geoenvironmental Engineering, 124(6), 479-491.
20. 20. Cabalar, A.F., Dulundu, K., Tuncay, K., 2013. Strength of Various Sands in Triaxial and Cyclic Direct Shear Tests. Engineering Geology, 156, 92-102.
21. 21. Yao, Y.P., Sun, D.A., Luo, T., 2004. A Critical State Model for Sands Dependent on Stress and Density, International Journal for Numerical and Analytical Methods in Geomechanics, 28(4), 323-337.
22. 22. Park, S.S., Jeong, S.W., 2015. Effect of Specimen Size on Undrained and Drained Shear Strength of Sand, Marine Geosources & Geotechnology, 33(4), 353-358.
23. 23. Skempton, A.W., 1954. The Pore Pressure Coefficients A and B, Geotechnique, 4(4), 143-147.
24. 24. Terzaghi, K., Peck, R.B., Mesri, G., 1996. Soil Mechanics in Engineering Practice, John Wiley & Sons, Inc. Third Edition, Printed in the United States of America.
25. 25. Ismail, M.A., Joer, H.A., Sim, W.H., Randolph, M.F., 2002. Effect of Cement Type on Shear Behavior of Cemented Calcareous Soil, Journal of Geotechnical and Geoenvironmental Engineering, 128(6), 520529.