Numerical Modeling of Ground Improvement Methods Tehran Metro Line 6 Excavation

Document Type : Research - Paper

Authors

1 M.Sc, Dept. of Mining, Petroleum & Geophysics Engineering, Shahrood University of Technology, Shahrood, Iran

2 Assistant Professor, Dept. of Mining, Petroleum & Geophysics Engineering, Shahrood University of Technology, Shahrood, Iran

Abstract

One of the most critical issues in weak grounds is soil improvement, which is considered reused in a new geotechnical structure or improves the current structure condition. In the present research, implementing a limited, finite element numerical method to predict the rate of ground settlement level before and after the implementation of ground improvement in the eastern access tunnel drilling process of Khorasan Square Station located in Tehran Metro Line 6. Since the tunnel route passes under residential buildings and shops, with the excavation of this part of the Khorasan Square Station project, large amounts of settlement exist on the ground surface, which cracked buildings and shop structures. Based on this, piling, fore poling, and anchoring improvement methods can be used for loose and fallen grounds that were modeled numerically by MIDAS GTS NZ software. In this research, in addition to investigating the performance of the mentioned methods, the effect of geometric parameters, including the covering of fore poling pipes, pile length, and the diameter of anchors, was investigated. The criteria for investigating, the Displacement occurred at ground level, and tunnel crown is considered. Results showed that all methods have been useful in reducing ground settlement and tunnel crown. Also, Among the above-mentioned improvement methods, the method of using the fore poling method with anchorage has reduced the plastic points surrounding the tunnel and also has a greater effect in reducing the settlement of the ground, so that it has reduced the maximum settlement of the ground surface by 50%.

Keywords

Main Subjects

References

  1. Kavitha, P. E., Beena, K. S., and Narayanan, K. P. (2016). “A review on soil–structure interaction analysis of laterally loaded piles”. Innovative Infrastructure Solutions, 1(1): 14.
  2. Loganathan, N., Poulos, H. G., and Xu, K. J. (2001). “Ground and pile-group responses due to tunneling”. Soils Found, 41(1): 57-67.
  3. فرعی، ا.، احترمی، ع.؛ 1398؛ "رده‌بندی ریسک سازه‌های سطحی و بررسی عملکرد شمع درجا در کاهش نشست‌های ناشی از حفر تونل‌های مترو در مناطق شهری (مطالعه موردی: متروی تبریز)". مهندسی زیر ساخت‌های حمل و نقل، سال پنجم، پیاپی هفدهم، ص 119-97.
  4. Bilotta, E., and Russo, G. (2010). “Use of a line of piles to prevent damages induced by tunnel excavation”. Journal of Geotechnical and Geoenvironmental Engineering, 137(3): 254-262.
  5. Fantera, L., Rampello, S., and Masini, L. (2016). “A mitigation technique to reduce ground settlements induced by tunnelling using diaphragm walls”. Procedia Engineering, 158: 254-259
  6. Moriwaki, T., and Satoh, T. (2009). “Method for determining the horizontal coefficient of permeability of clay”. Proceedings of the 44th Annual Presentation of Geotechnical Engineering, 219-220.
  7. Harazaki, I., Aono, H., Matsuda, A., Aoki, T., and Hakoishi, Y. (1998). “Field observation of large tunnel supported by umbrella method: Case of Maiko Tunnel in Kobe, Japan”. Proceedings of the World Tunnel Congress, 98: 1009-1014.
  8. Aksoy, C. O., and Onargan, T. (2010). “The role of umbrella arch and face bolt as deformation preventing support system in preventing building damages”. Tunnelling and Underground Space Technology, 25(5): 553-559.
  9. Arrizabalaga, I. A. (2014). “Comparison of the installation of strand with steel bar tendons in anchored drilled shaft wall”. Master Thesis, Arlington College, University of Texas
  10. Lee, Y. J., and Yoo, C. S. (2006). “Behaviour of a bored tunnel adjacent to a line of loaded piles”. Tunneling and Underground Space Technology, 21(3-4): 370.
  11. Mollahasani, A. (2014). “Application of Submerged Grouted Anchors in Sheet Pile Quay Walls”. D. Thesis, Dipartimento di ingegneria civile, Università di Bologna.
  12. Chang-fu, C., and Shu-jun, X. (2008). “Mechanical mechanism analysis of tension type anchor based on shear displacement method”. Institute of Geotechnical Engineering, Hunan University, Changsha 410082, China, Journal of Central South University,15: 106-111.
  13. بخشنده امنیه، ح.، زمزم، م.، موسوی، ا.، طریق ازلی، ص.؛ 1392؛ "انتخاب مناسب‌ترین مجموعه‌ی بهسازی خاک در حفاری مکانیزه‌ی تونل خط 7 متروی تهران". نشریه مهندسی تونل و فضاهای زیرزمینی دوره 2، شماره2، ص 154-145.
  14. کرم نیای فر، م.، دهقان، ع. ن.؛ 1397؛ "بررسی اثر سیستم پیش نگهداری(فورپولینگ) بر کنترل نشست سطح زمین ناشی از حفاری تونلها ی کم عمق شهری تحت بارگذاری ترافیک ریلی". نشریه مهندسی تونل و فضاهای زیرزمینی، دوره 7، شماره 2، ص 85-63.
  15. شرکت مهندسان مشاور دریا خاک پی؛ 1389؛ "گزارش مطالعات ژئوتکنیک بخش جنوبی خط 6 مترو تهران". شرکت راه آهن شهری تهران و حومه (مترو)، تهران، ایران.
  16. شرکت مهندسی آهاب؛ 1397؛ "دفتر فنی و اجرایی ایستگاه میدان خراسان". گزارشات دفتر فنی و مهندسی، تهران، ایران.
  17. Burkovič, K., Smirakova, M., and Mateckova, P. (2017). “Testing and Modelling of Concrete Pile Foundations”. In Key Engineering Materials, Trans Tech Publications Ltd, 738: 287-297.
  18. بخشنده امینه، ح.، زمزم، م.؛ 1394، "کنترل نشست زمین در تونل سازی مکانیزه در محیط‌های شهری با انجام اقدامات اصلاح مؤثر درتونل خط 7 متروی تهران". نشریه علمی مهندسی معدن، دوره دهم، شماره 27، ص 45-59.

Files

History

  • Receive Date: 20 November 2020
  • Revise Date: 30 November 2021
  • Accept Date: 28 August 2021

Share

How to cite

Statistics