Assessment of Excavation Method of Obajana and Ewekoro Limestone Deposits
Earth Sciences
Volume 3, Issue 2, April 2014, Pages: 42-49
Received: Feb. 19, 2014; Accepted: Apr. 8, 2014; Published: Apr. 10, 2014
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Authors
SALIU Muyideen Alade, Department of Mining Engineering, he Federal University Technology, Akure Ondo State, Nigeria
SHEHU Shaib Abdulazeez, Department of Mineral Resources Engineering, Kogi State Polytechnic, Lokoja, Nigeria
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Abstract
The research work assessed the optimum excavation method of limestone deposits at Obajana in Kogi State and Ewekoro in Ogun state. Geological mapping was carried out to measure the orientations of discontinuities. The orientation data obtained were plotted on stereonets to determine pole concentration and major joint sets using Dips 5.0 software from Rocscience. Two joint sets were identified in Obajana with orientations of 720/0890 and 880/2210 while three joint sets with orientations of 610/0480, 160/2800 and 900/1400 were identified in Ewekoro quarry face. Schmidt hammer hardness and Unit weight tests were performed. The results obtained were used to evaluate the Uniaxial Compressive Strength (UCS) and consequently, the Point load index (Is) of the rock studied. The excavation method was assessed using Discontinuity Spacing Index (If), the Point load index (Is) and the Geological Strength Index (GSI). The discontinuity spacing index was evaluated from the major joint sets identified and the determination of the volumetric joint count (Jv).The geological strength index was estimated using an inbuilt chart of RocLab 1.0 from Rocscience. Excavation assessments revealed that “Very Hard Ripping” is a possible method of excavating Obajana and Ewekoro Type III deposits while the less dense Type I deposit of Ewekoro can be “Ripped”. The only feasible excavation method for Ewekoro type II deposit is “Blasting”.
Keywords
Dip, Dip Direction, Ripping, Blasting, Dense, Excavation, Joint Sets
To cite this article
SALIU Muyideen Alade, SHEHU Shaib Abdulazeez, Assessment of Excavation Method of Obajana and Ewekoro Limestone Deposits, Earth Sciences. Vol. 3, No. 2, 2014, pp. 42-49. doi: 10.11648/j.earth.20140302.12
References
[1]
Hudson, J.A. and Harrison, J.P. (1997). Engineering Rock Mechanics: an introduction to the principles: Pergamon Press, Elsevier Ltd., Oxford, UK, p. 44
[2]
Tsiambaos, G. and Saroglou, H. (2010). Excavatability assessment of rock masses using the geological strength index (GSI): Bulletting of Engineering Geology and Environment, Vol. 69, pp. 13–27.
[3]
Duncan, N. (1969). Engineering Geology and Rock Mechanics, vol. 2: Leonard Hill, London, p. 352
[4]
Franklin, J.A., Broch, E. and Walton, G. (1971). Logging the mechanical character of rock: Transactions of the Institution of Mining and Metallurgy 80A, pp. 1–9.
[5]
Atkinson, T. (1971). Selection of open pit excavating and loading equipment: Transactions of the Institution of Mining and Metallurgy 80A, pp. 101–129
[6]
Goran, B., Rolf, C. and Leif, L. (2004). Choice of rock excavation methods for the Swedish deep repository for spent nuclear fuel: Swedish Nuclear Fuel and Waste Management Company, Stockholm, Sweden. Retrieved on 28th March, 2011 from www.skb.se, p. 146
[7]
Hoek, E., (2006). Practical Rock Engineering: Evert Hoek consulting Inc., North Vancouver, B.C., Canada. Retrieved on 27th February, 2010 from www.rocscience.com, p. 237
[8]
Pettifer, G.S. and Fookes, P.G. (1994). A revision of the graphical method for assessing the excavatability of rock: Quarterly Journal of Engineering Geology 27, pp. 145–164.
[9]
Kentli B. and Topal, F.T. (2004). Evaluation of rock excavatability and slope stability along a segment of motorway, Pozanti, Turkey: Journal of Environmental Geology, vol. 46: pp. 83–95.
[10]
Gurocak, Z., Alemdag, S. and Zaman, M.M. (2008). Rock slope stability and excavatability assessment of rocks at the Kapikaya dam site, Turkey: Journal of Engineering Geology, vol. 96(1–2): pp. 17–27.
[11]
Abdullatif, O.M. and Cruden, D.M. (1983). The relationship between rock mass quality and ease of excavation: Bulletin of Engineering Geology and Environment, vol. 28: pp. 183–187.
[12]
Wyllie, D.C. and Mah, C.W. (2005). Rock Slope Engineering: civil and mining (4th Edition): Spon Press, Taylor and Francis Group, London and New York, p. 431
[13]
International Society for Rock Mechanics, ISRM. (1981). Rock characterization, testing and monitoring. In: Brown, E.T. (edition) ISRM suggested methods. Pergamon Press, Oxford, UK, p. 211.
[14]
American Society for Testing Materials (ASTM), (1994). Annual Book of ASTM Standards-construction: Soil and Rocks. ASTM Publication, Vol. 04.08.978, p. 975
[15]
Aydin, A. and Basu, A. (2005). The Schmidt hammer in rock material characterization: Journal of Engineering Geology, 81 (2005), Elsivier International, pp. 1-14.
[16]
Xu, S., Grasso, P. and Mahtab, A. (1990). Use of Schmidt Hammer for estimating mechanical properties of weak rock: Proc. 6th International IAEG Congress, vol. 1. Balkema, Rotterdam, pp. 511 –519.
[17]
Osman, A. (2010). Geomechanical properties and rock mass quality of the carbonates rus formation, Dammam Dome, Saudi Arabia: Arabian Journal for Science and Engineering, Volume 35, Number 2A. pp. 173-197.
[18]
Broch, E. and Franklin, J. A. (1972). The point load test: Int. J. Rock Mech. Min. Sci. (9), Pp 669 – 697.
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