Geotechnical Challenges of Tehran Metro Line 7 (South Northern Route)

Farzad Sadjadi, Ahad Bagherzadeh Khalkhali


Tunneling in urban areas, has raised the level of difficulty and challenge in respecting the constraints deriving from human presence and, therefore, the necessity for the study of geological and geotechnical properties and parameter, classification of the soils according to their engineering behavior, choosing the right TBM, determine groundwater level and determining possible geological hazards. In this paper some geological and geotechnical study took place along the tunnel route. This investigation is done by the result of 73 machinery borehole and 32 manual borehole that took place in the process of studying the tunnel route and continued by the result of field tests and laboratory tests and according to the result, the geological zone classified in 6 zone in tunnel route; due to the result of Cerchar abrasivity test and since Alluvial soil is the main soil in most of the tunneling route, the excavation soil classified as highly abrasive. In some part of tunneling there is a risk of clogging due to the high amount of clay. Based on the results of Lofran tests the permeability of most of the classified soils in route of the tunnel was obtained less that 10E-7 m/s.


Liquefaction Potential Index; Geographic Information System (GIS); Yangon City; Liquefaction Potential Map; SPT Data.


Japan International Cooperative Agency (JICA) "Separate Seismic Micro-zoning Report of Tehran, Great" prepared for Tehran's Large Earthquake and Environmental Studies Center, 381 pages, (2001).

Jafari, M. & Associates "Report of Seismic Zonal Survey of South Tehran," International Institute of Seismology and Earthquake Engineering, (2002).

Jafari, M. and colleagues "Seismic micro zonation report of northern Tehran from the point of view of site conditions", International Institute of Seismology and Earthquake Engineering, (2002).

Sahel Consulting Engineers "Geological and Geotechnical Studies Report of Tehran Metro Line 7", (2011).

Jerome B. O’Carroll, A Guide to Planning, Constructing and Supervising EARTH PRESSURE BALANCE TBM TUNNELING, Parsons Brinckerhoff Inc, (2005).

Guglielmetti, Vittorio, Piergiorgio Grasso, Ashraf Mahtab, and Shulin Xu, eds. Mechanized tunnelling in urban areas: design methodology and construction control. CRC Press, 2008.

ITA, WF. "Mechanized Tunnelling: Recommendations and Guidelines for Tunnel Boring Machines (TBMs)." (2000).

Thewes M., TBM tunneling challenges redefining the state of the art, Keynote lecture ITAAITES WTC, PRAGUE, (2007).

BTS, ICE. "Closed-face Tunnelling Machines and Ground Stability–a Guideline for Best Practice." (2005): 10.

Clough, G. Wayne, Bryan P. Sweeney, and Richard J. Finno. “Measured Soil Response to EPB Shield Tunneling.” Journal of Geotechnical Engineering 109, no. 2 (December 1983): 131–149. doi:10.1061/(asce)0733-9410(1983)109:2(131).

Thewes, Markus, and W. E. R. N. E. R. Burger. "Clogging risks for TBM drives in clay." Tunnels & Tunnelling International 36, no. 6 (2004).

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DOI: 10.28991/cej-0309161


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