Mechanical and thermal properties of cemented tailings materials at early ages: Influence of initial temperature, curing stress and drainage conditions

The cementitious construction material, cemented paste backfill (CPB), is extensively used in underground mining operations worldwide. After the CPB is placed in the field, the evolution of its mechanical and thermal properties strongly affects its stability and the heat transfer within it. An experimental setup is designed to enable the curing of CPB samples under different stresses, filling rates, initial temperatures and drainage conditions as well as the monitoring of the changes in capillary pressure, temperature, amount of drained water and electrical conductivity in the CPB samples during curing. Furthermore, extensive testing is carried to investigate the combined effects of initial temperature, curing stress and drainage on the mechanical, microstructural and thermal properties of CPB. The obtained results reveal that these properties are strongly influenced by the initial backfill temperature, curing stress and drainage conditions, and their interactions. These can significantly affect the cement hydration, capillary pressure development and pore structure of CPB. (C) 2016 Elsevier Ltd. All rights reserved.