ORIGINAL PAPER Coupled Modeling of Temperature Distribution and Evolution in Cemented Tailings Backfill Structures that Contain Mineral Admixtures Di Wu • Mamadou Fall • Si-jing Cai Received: 21 February 2012 / Accepted: 23 April 2012 / Published online: 8 May 2012 Ó Springer Science+Business Media B.V. 2012 Abstract Cemented paste backfill (CPB, a mixture of tailings, water and binder) is widely utilized to fill underground mine voids. To achieve a good, econom- ical performance, one approach is to proportionally use mineral admixtures such as fly ash and slag as partial substitutes for Portland cement. Binder hydration is one of the most significant factors that can generate heat within hydrating CPB structures, which in turn, influences the mechanical and hydraulic properties of CPB, as well as the pore structure within CPB. However, the temperature evolution due to the hydra- tion of Portland cement that contains fly ash or slag is different from that of hydration with solely Portland cement. Hence, in consideration of the heat generated by both binder hydration and transferred between CPB and its surrounding media, a numerical model is developed to predict and determine the temperature development within CPB that contains mineral admix- tures. After that, data from field and laboratory studies are employed to validate the developed model. The validation results demonstrate a good consistency between the model and the field and laboratory studies. Consequently, the proposed model is applied to simulate and determine the temperature evolution with time via mineral admixtures, binder content, initial rock and CPB temperatures, stope geometry, backfill- ing rate, curing time and backfilling strategy. The obtained results will contribute to better designs and preparation of CPB mixtures, as well as predict the temperature distribution within CPB structures. Keywords Cemented paste backfill  Tailings  Fly ash  Slag  Binder hydration  Heat transfer  Temperature development  Coupled model 1 Introduction Underground mining is a significant way to extract ore from the earth, but at the same time, produces a huge amount of solid waste such as tailings and also creates large underground mine voids (Yilmaz et al. 2004). On the one hand, tailing dams should be built to store accumulated waste tailings on the ground surface, but this is not only a potential safety hazard, it also increases costs. Besides the aforementioned problems, the surface disposal of tailings can cause serious environmental pollution, such as acid mine drainage. On the other hand, large underground voids can result in surface subsidence and the hidden danger of instability for the mining workplace (Nasir and Fall 2009). However, by utilizing waste tailings to fill underground voids, mine backfill- ing can effectively solve or reduce the problems mentioned above. Nowadays, as an environmentally D. Wu  M. Fall (&) Department of Civil Engineering, University of Ottawa, Canada, 161 Colonel by, Ottawa, ON K1N 6N5, Canada e-mail: mfall@uottawa.ca D. Wu  S. Cai Department of Resource Engineering, University of Science and Technology Beijing, Beijing, China 123 Geotech Geol Eng (2012) 30:935–961 DOI 10.1007/s10706-012-9518-1