Shear Strength of a Cemented Paste Backfill Submitted to High Confining Pressure

Abstract:

Deep mining operations require special measures in order to keep safe and economic aspects. After mine ore is extracted, voids are created and need to be filled with high-strength, low-cost materials. Cemented Paste Backfill (CPB) has recently become one of the main alternatives in filling stopes. Although numerous papers have mentioned the magnitudes of the strength of this material, its behavior under high confining pressures is still not well understood. Therefore, the purpose of this study is to increase the knowledge regarding the CPB behavior. Triaxial compression tests were performed using a Hoek Cell and Load Frame System under high confining pressures. Samples with two different binder contents were used in order to obtain the CPB strength improvement. Besides the self-weight consolidation curing method, samples were subjected to a different curing method that simulated a zero gravity condition (rotating wheel) in the first curing day to compare their mixture properties. The results suggested that both curing method and binder content have influenced the geomechanical properties of Cemented Paste Backfill. By increasing the curing time, the CPB shear strength has increased slightly, whereas specimens with higher binder content presented a significant increase in shear strength values.

• Periodical: Applied Mechanics and Materials (Volume 858)
• Pages: 219-224
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.858.219
• Online since: November 2016
• Authors: Eduardo Eiler Batista de Araújo, Dragana Simon, Fagner Alexandre Nunes de França*, Osvaldo de Freitas Neto, Olavo Francisco dos Santos Jr.
• Keywords: Cemented Paste Backfill, Curing Process, Mine Tailings

References

[1] T. Belem, M. Benzaazoua, B. Bussière, Mechanical behavior of cemented paste backfill, 53rd Annual Conf. of the Canadian Geotechnical Society, Montreal, Canada. (2000).

[2] T. Belem, M. Benzaazoua, An overview on the use of paste backfill technology as a ground support method in cut-and-fill mines, 5th Int. Symp. on Ground support in Mining and Underground Construction. 2004, Perth, Australia, Tayler & Francis Group, London, (2004).

DOI: 10.1201/9780203023921-81

[3] A. M. G. M. I. Abdelaal, Early Age Mechanical Behavior and Stiffness Development of Cemented Paste Backfill with Sand, Ph.D. Thesis, Department of Civil Engineering, University of Toronto, Toronto, Ontario, Canada. (2011).

[4] E. E. B. Araujo, F. A. N. França, Geotechnical characterization of soil-cement mix used in mining operations, Brazilian Conference on Soil Science, Natal, Brazil. (2015) (in Portuguese).

[5] C. Stalteri, The stiffness evolution and mechanical behavior of cemented paste backfill with sand at different curing ages. University of Toronto, Canada. (2014).