Empirical Support Design for Proposed Diversion Tunnels at Dasu Dam Site Pakistan

Muhammad Bilal; Muhammad Zaka Emad; Fawad Ul Hassan; Zaheer Ahmed

doi:10.52763/PJSIR.PHYS.SCI.64.2.2021.131.136

Muhammad Bilal Department of Mining Engineering, Balochistan University of Information Technology Engineering and Management Sciences, Quetta, Pakistan
Muhammad Zaka Emad Department of Mining Engineering, University of Engineering and Technology, Lahore, Pakistan bilalkhan4p@mail.com
Fawad Ul Hassan Department of Mining Engineering, Balochistan University of Information Technology Engineering and Management Sciences, Quetta, Pakistan
Zaheer Ahmed Department of Mining Engineering, Balochistan University of Information Technology Engineering and Management Sciences, Quetta, Pakistan

DOI: https://doi.org/10.52763/PJSIR.PHYS.SCI.64.2.2021.131.136

Keywords: rock mass classification, RMR, Q-system

Abstract

This research work presents the rock mass characteristics and tunnel support system recommendations for hydroelectric power tunnels at Dasu dam site Pakistan. Two inverted U-shaped tunnels are proposed at the left bank of Indus river. The tunnels have inlet portals at an elevation of 773.00 m and outlet portals at an elevation of 758.00 m. The thickness of rock cover above the tunnels is between 100 and 200 m. Three types of rock are encountered at project site including Granulite, Amphibolite and Gabbronorite. Granulite rocks are encountered along the alignment of tunnels. Rock mass is classified using Rock mass rating (RMR) and Tunneling quality index (Q system). Support system is suggested based on values of Q and RMR. Correlation between Q-index and RMR is also derived.