Geomechanics and Engineering

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Numerical modeling of uplift resistance of buried pipelines in sand, reinforced with geogrid and innovative grid-anchor system

  • Received : 2015.03.15
  • Accepted : 2015.10.28
  • Published : 2015.12.25
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Abstract

Reinforcing soils with the geosynthetics have been shown to be an effective method for improving the uplift capacity of granular soils. The pull-out resistance of the reinforcing elements is one of the most notable factors in increasing the uplift capacity. In this paper, a new reinforcing element including the elements (anchors) attached to the ordinary geogrid for increasing the pull-out resistance of the reinforcement, is used. Thus, the reinforcement consists of the geogrid and anchors with the cylindrical plastic elements attached to it, namely grid-anchors. A three-dimensional numerical study, employing the commercial finite difference software FLAC-3D, was performed to investigate the uplift capacity of the pipelines buried in sand reinforced with this system. The models were used to investigate the effect of the pipe diameter, burial depth, soil density, number of the reinforcement layers, width of the reinforcement layer, and the stiffness of geogrid and anchors on the uplift resistance of the sandy soils. The outcomes reveal that, due to a developed longer failure surface, inclusion of grid-anchor system in a soil deposit outstandingly increases the uplift capacity. Compared to the multilayer reinforcement, the single layer reinforcement was more effective in enhancing the uplift capacity. Moreover, the efficiency of the reinforcement layer inclusion for uplift resistance in loose sand is higher than dense sand. Besides, the efficiency of reinforcement layer inclusion for uplift resistance in lower embedment ratios is higher. In addition, by increasing the pipe diameter, the efficiency of the reinforcement layer inclusion will be lower. Results demonstrate that, for the pipes with an outer diameter of 50 mm, the grid-anchor system of reinforcing can increase the uplift capacity 2.18 times greater than that for an ordinary geogrid and 3.20 times greater than that for non-reinforced sand.

Keywords

References

  1. Bransby, M.F., Newson, T.A., Davies, M.C.R. and Brunning, P. (2002), "Physical modeling of the upheaval resistance of buried offshore pipelines", Proceedings of the 4th International Conference on Physical Modeling in Geomechanics, St. Johns, NY, USA, July, pp. 899-904.
  2. Cheuk, C.Y., White, D.J. and Bolton, M.D. (2005), "Deformation mechanisms during the uplift of buried pipelines in sand", Proceedings of the International Conference on Soil Mechanics and Geotechnical Engineering, Osaka, Japan, September, pp. 1685-1688.
  3. Cheuk, C.Y., White, D.J. and Bolton, M.D. (2008), "Uplift mechanics of pipes buried in sand", J. Geotech. Geoenviron. Eng., 134(2), 154-163. https://doi.org/10.1061/(ASCE)1090-0241(2008)134:2(154)
  4. Choobbasti, A.V., Vahdatirad, M., Firouzian Bandpey, S., Barari, A. and Rezaei, D. (2009), "Modeling of the uplift response of buried pipelines", Electron. J. Geotech. Eng., 14, 001-015.
  5. Dikin, E.A. (1994), "Uplift resistance of buried pipelines in sand", J. Soil. Found., 34(2), 41-48.
  6. Faizi, K., Jahed Armaghani, D., Momeni, E., Nazir, R. and Tonnizam Mohamad, E. (2014), "Uplift resistance of buried pipelines enhanced by geogrid", Soil Mech. Found. Eng., 51(4), 188-195. https://doi.org/10.1007/s11204-014-9276-6
  7. Finch, M. (1999), "Upheaval buckling and floatation of rigid pipelines: the influence of recent geotechnical research on the current state of the art", Offshore Technology Conference, Houston, TX, USA, May.
  8. Ghosh, A. and Bera, A.K. (2010), "Effect of geotextile ties on uplift capacity of anchors embedded in sand", J. Geotech. Geoenviron. Eng., 28(5), 567-577. https://doi.org/10.1007/s10706-010-9313-9
  9. Hataf, N., Boushehrian, A.H. and Ghahramani, A. (2010), "Experimental and numerical behavior of shallow foundations on sand reinforced with geogrid and grid-anchor under cyclic loading", Scientia Iranica. Transaction A, Civil Engineering, 17(1), 1-10.
  10. Huang, B., Liu, J., Lin, P. and Ling, D. (2014), "Uplifting behavior of shallow buried pipe in liquefiable soil by dynamic centrifuge test", The Scientific World Journal, Article ID 838546.
  11. Itasca (2012), FLAC-3D Version 5.0, Itasca Consulting Group, Inc., Minneapolis, MN, USA.
  12. Jahed Armaghani, D., Faizi, K., Hajihassani, M., Tonnizam Mohamad, E. and Nazir, R. (2015), "Effects of soil reinforcement on uplift resistance of buried pipeline", J. Measure., 64, 57-63.
  13. Keskin, M.S. (2015), "Model studies of uplift capacity behavior of square plate anchors in geogridreinforced sand", Geomech. Eng., Int. J., 8(4), 595-613. https://doi.org/10.12989/gae.2015.8.4.595
  14. Lee, H. (2010), "Finite element analysis of a buried pipeline", Master's Thesis; University of Manchester, Manchester, UK.
  15. Mohri, Y., Kawabata, T. and Fujita, N. (2001), "Large-scale experiment on shallow cover for buried pipeline reinforced with geosynthetics", J. Pipeline Syst. Eng. Pract., 52, 1-13.
  16. Mosallanezhad, M., Hataf, N. and Ghahramani, A. (2007), "Experimental study of bearing capacity of granular soils, reinforced with innovative grid-anchor system", J. Geotech. Geol. Eng., 25(1), 123-137. https://doi.org/10.1007/s10706-006-0010-7
  17. Mosallanezhad, M., Hataf, N. and Ghahramani, A. (2010), "Three dimensional bearing capacity analyses of granular soils, reinforced with innovative grid-anchor system", Iran. J. Sci. Technol., Transaction B: Eng., 34(4), 419-431.
  18. Newson, T.A. and Deljoui, P. (2006), "Finite element modeling of upheaval buckling of buried offshore pipelines in clayey soils", Soil Rock Behavior Model., 351-358.
  19. Niroumand, H. and Kassim, K.A. (2013), "A review on uplift response of symmetrical anchor plates embedded in reinforced sand", Geomech. Eng., Int. J., 5(3), 187-194. https://doi.org/10.12989/gae.2013.5.3.187
  20. Niroumand, H. and Kassim, K.A. (2014a), "Uplift response of circular plates as symmetrical anchor plates in loose sand", Geomech. Eng., Int. J., 6(4), 321-340. https://doi.org/10.12989/gae.2014.6.4.321
  21. Niroumand, H. and Kassim, K.A. (2014b), "Experimental and numerical modeling of uplift behavior of rectangular plates in cohesionless soil", Geomech. Eng., Int. J., 6(4), 341-358. https://doi.org/10.12989/gae.2014.6.4.341
  22. Niroumand, H. and Kassim, K.A. (2014c), "Square plates as symmetrical anchor plates under uplift test in loose sand", Geomech. Eng., Int. J., 6(6), 593-612. https://doi.org/10.12989/gae.2014.6.6.593
  23. Niroumand, H., Kassim, K.A. and Nazir, R. (2013), "The influence of soil reinforcement on the uplift response of symmetrical anchor plate embedded in sand", J. Measure., 46(8), 2608-2629.
  24. Robert, D. and Thusyanthan, N. (2015), "Numerical and experimental study of uplift mobilization of buried pipelines in sands", J. Pipeline Syst. Eng. Pract., 6(1), CID:04014009.
  25. Rowe, R.K. and Davis, E.H. (1982), "The behaviour of anchor plates in sand", Geotechnique, 32(1), 025-041. https://doi.org/10.1680/geot.1982.32.1.25
  26. Saboya, F.A., Santiago, P.C., Martins, R.R., Tibana, S., Ramires, R.S. and Araruna, J.T. (2012), "Centrifuge test to evaluate the geotechnical performance of anchored buried pipelines in sand", J. Pipeline Syst. Eng. Pract., 3(3), 84-97. https://doi.org/10.1061/(ASCE)PS.1949-1204.0000105
  27. Selvadurai, A.P.S. (1989), "The enhancement of the uplift capacity of buried pipelines by the use of geogrids", J. Geotech. Geoenviron. Eng., 124(8), 211-216.
  28. Thusyanthan, N.I., Ganesan, S.A. Bolton, M.D. and Allan, P. (2008), "Upheaval buckling resistance of pipelines buried in clayey backfill", Proceedings of the 18th International Offshore and Polar Engineering Conference, Vancouver, BC, Canada, July, pp. 6-11.
  29. Trautmann, C.H., O'Rourke, T.D. and Kulhawy, F.H. (1985), "Uplift force-displacement response of buried pipe", J. Geotech. Eng., 111(9), 1061-1076. https://doi.org/10.1061/(ASCE)0733-9410(1985)111:9(1061)
  30. Wang, J., Haigh, S.K., Forrest, G. and Thusyanthan, N.I. (2012), "Mobilization distance for upheaval buckling of shallowly buried pipelines", J. Pipeline Syst. Eng. Pract., 3(4), 106-114. https://doi.org/10.1061/(ASCE)PS.1949-1204.0000099
  31. White, D.J., Barefoot, A.J. and Bolton, M.D. (2001), "Centrifuge modeling of upheaval buckling in sand", Int. J. Phys. Model. Geotech., 1(2), 019-028. https://doi.org/10.1680/ijpmg.2001.010202
  32. White, D.J., Cheuk, C.Y. and Bolton, M.D. (2008), "The uplift resistance of pipes and plate anchors buried in sand", Geotechnique, 58(10), 771-779. https://doi.org/10.1680/geot.2008.3692
  33. Zhu, H.H., Mei, G.X., Xu, M., Liu, Y. and Yin, J.H. (2014), "Experimental and numerical investigation of uplift behavior of umbrella-shaped ground anchor", Geomech. Eng., Int. J., 7(2), 165-181. https://doi.org/10.12989/gae.2014.7.2.165

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