HELİSEL ANKRAJ PLAKALARININ TABAKALI ZEMİNLERDEKİ ÇEKME KAPASİTELERİNİN İNCELENMESİ

Öz

Bu çalışmada, tabakalı zeminlere (kil-kum) inşa edilen helisel ankraj plakalarının çekme kapasitesi laboratuvar ortamında model deneyler yapılarak araştırılmıştır. Deneylerde 50mm çapında helisel model ankraj plakası kullanılmıştır. Model deneylerde tabakalı zeminlerde kum tabakası sıkılığının ankraj plakasının çekme kapasitesi üzerindeki etkisi araştırılmıştır. Kum sıkılığının artması ile ankraj plakasının çekme kapasitesinin arttığı görülmüştür. Ayrıca, model deney düzeneği, sonlu elemanlar yöntemi kullanan PLAXIS 2D bilgisayar programı ile modellenip analiz edilmiştir. Elde edilen deney sonuçları sayısal sonuçlarla karşılaştırılmış ve gerekli öneriler yapılmıştır.

Anahtar Kelimeler

• Helisel ankraj, tabakalı zemin, çekme kapasitesi, zemin sıkılığı

An Investigation of Uplift Capacity of Helical Anchor Plates in Layered Soil

Öz

In this study, uplift capacity of helical anchor plate embedded in layered soil (clay-sand) was investigated by conducting small scale model tests in laboratory. Model anchor plate with 50mm diameters of helix were used in the tests. The parameter investigated for the uplift capacity is density of sand. It was observed that uplift capacity of anchor plate increased with increasing density of sand. In addition, the tests were modelled by using the finite element program called PLAXIS 2D. The experimental results were compared with the numerical results and finally, some necessary suggestions for continuation of this work were put forward.

Anahtar Kelimeler

• Helical anchor, layered soil, uplift capacity, density of soil

Kaynakça

1. Adams, J.I., Hayes, D.C., 1967, “The uplift capacity of shallow foundations”, Ontario Hydro Research Quarterly, Cilt 19, Sayı 1, ss. 1–13
2. ASTM D 854-14: Standard Test Methods for Specific Gravity of Soil Soils by Water Pycnometer.
3. ASTM D 3080-98: Standard Test Methods for Direct Shear Test of Soils Under Consolidated Drained Conditions.
4. ASTM D 4253-00: Standart Test Methods for Maximum Index Density and Unit Weight of Soils Using a Vibratory Table.
5. ASTM D 4254-00: Standart Test Methods for Minimum Index Density and Unit Weight of Soils and Calculation of Relative Density.
6. Balla, A., 1961, “The Resistance to Breaking out of Mushroom Foundations for Pylons in Proc.”, V Int. Conf. Soil Mech. Found. Eng., Paris, France, 1, 569,
7. Chattopadhyay, B. C., Pise, P. J., 1986, “Uplift Capacity of Piles in Sand”, Journal of Geotechnical Engineering, Cilt 112, Sayı 9, ss. 888-904
8. Das, B. M., 1978, “Model tests for uplift capacity of foundations in clay”, Soils and Foundations, Cilt 18, Sayı 2, ss. 17

9. Das, B.M., Seeley, G. R., 1975, “Breakout Resistance of Horizontal Anchors”, Journal of Geotechnical Engineering Div., ASCE, Cilt 101, Sayı 9, ss. 999
10. Demir, A., 2011, “Yumuşak Kil Zemin Üzerinde Güçlendirilmiş Stabilize Dolguya Oturan Yüzeysel Temellerin Analizi”, Doktora Tezi, Çukurova Üniversitesi, Fen Bilimleri Enstitüsü, Adana
11. Dickin, E. A., 1988, “Uplift Behaviour of Horizontal Anchor Plates in Sand”, J Geotech Eng Div, ASCE, Cilt 114, Sayı 11, ss. 1300–1317
12. Dickin, E. A., Leung, C. F., 1990, “Performanceof Piles With Enlarged Bases Subject to Uplift Forces” , Canadian Geotech. J., Cilt 27, ss. 546-556
13. Dickin, E. A., Leung, C. F., 1992, “The Influence of Foundation Geometry on The Uplift Behaviour of Piles With Enlarged Bases”, Canadian Geotech. J., Cilt 29, ss. 798-505
14. Ghaly, A. M. Hanna, A. M., Hanna, M., 1991. “Uplift Behaviour of Screw Anchors in Sand”, II: Hydrostatic and Flow Conditions, Journal of Geotechnical Engineering., ASCE, Cilt 117, Sayı 5, ss. 794- 808
15. Merifield, R. S., 2011, “Ultimate Uplift Capacity of Multiplate Helical Type Anchors in Clay”, Journal Of Geotechnıcal And Geoenvıronmental Engıneerıng, Cilt 137, Sayı 7, ss. 704-716
16. Meyerhof, G. G., Adams, J. I., 1968, “The Ultimate Uplift Capacity of Foundations”, Canadian Geotech. J., Cilt 5, Sayı 4, ss. 225
17. Mitsch, M. P., Clemence, S. P., 1985, “Uplift capacity of helix anchors in sand”, Uplift Behavior of Anchor Foundations in Soil, ASCE, New York, ss. 26–47,
18. Niroumand H., Kassim K. A., Nazir R., 2011, “Uplift Capacity of Anchor Plates in Two-Layered Cohesive-Frictional Soils”, Journal of Applied Science, Cilt 11, Sayı 3, ss. 589-591
19. Ok B., 2014, “Ankraj Plakalarınının Farklı Zemin Koşullarındaki Çekme Kapasitelerinin İncelenmesi”, Yüksek Lisans Tezi, Osmaniye Korkut Ata Üniversitesi, Fen Bilimleri Enstitüsü, Osmaniye
20. Patra, N. R., Deograthias, M., James, M., 2004, “Pullout Capacity of Anchor Piles”, Electronic Journal of Geotechnical Engineering (EJGE), ss. 2004-0340
21. Rowe, R. K., Davis., E. H., 1982, “The Behaviour of Anchor Plates in sand”. Geotechnique, Cilt 32, Sayı. 1, ss. 25-41
22. Saran, S., Ranjan G., Nene A. S., 1986, “Soil anchors and constitutive laws”, Journal of Geotechnical Engineering, Cilt 112, Sayı 12, ss. 1084-1100
23. Sutherland, H.B., Finlay, T.W., Fadl, M.O., 1982, “Uplift capacity of embedded anchors in sand”, In Proceedings of the 3rd InternationalConference on the Behaviour of Offshore Structures, Cambridge, Mass., 2, ss. 451–463,
24. Stewart W., 1985, “Uplift Capacity of Circular Plate Anchors in Layered Soil”, Can. Geotech. J. Cilt 22, ss. 589-592
25. Vesic, A. S., , 1971, “Breakout Resistance of Objects Embedded in Ocean Bottom”, Journal of Soil Mech. Found. Div., ASCE, Cilt 97, Sayı 9, ss. 1183