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Studia Geotechnica et Mechanica

The Journal of Wroclaw University of Technology

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Tunnel support design by comparison of empirical and finite element analysis of the Nahakki tunnel in mohmand agency, pakistan

Asif Riaz / Syed Muhammad Jamil / Muhammad Asif / Kamran Akhtar
Published Online: 2016-04-18 | DOI: https://doi.org/10.1515/sgem-2016-0008


The paper analyses the geological conditions of study area, rock mass strength parameters with suitable support structure propositions for the under construction Nahakki tunnel in Mohmand Agency. Geology of study area varies from mica schist to graphitic marble/phyllite to schist. The tunnel ground is classified and divided by the empisical classification systems like Rock mass rating (RMR), Q system (Q), and Geological strength index (GSI). Tunnel support measures are selected based on RMR and Q classification systems. Computer based finite element analysis (FEM) has given yet another dimension to design approach. FEM software Phase2 version 7.017 is used to calculate and compare deformations and stress concentrations around the tunnel, analyze interaction of support systems with excavated rock masses and verify and check the validity of empirically determined excavation and support systems.

Keywords: rock mass strength parameters; rock mass classification; FEM analysis; Phase2; tunnel support design


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About the article

Published Online: 2016-04-18

Published in Print: 2016-03-01

Citation Information: Studia Geotechnica et Mechanica, Volume 38, Issue 1, Pages 75–84, ISSN (Online) 2083-831X, ISSN (Print) 0137-6365, DOI: https://doi.org/10.1515/sgem-2016-0008.

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© 2016 Asif Riaz et al., published by De Gruyter Open. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. BY-NC-ND 3.0

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