Laboratory tests for mine fills and barricade bricks

The recent spate of catastrophic fill barricade failures in underground hydraulic fill mines in Australia and overseas, have resulted in significant economic loss and loss of life. The term 'hydraulic fill' refers to the coarser fraction of a deslimed mine tailings slurry, which is placed in underground voids to improve mine efficiency and operation. A substantial body of research and consulting work has been conducted at the School of Engineering, James Cook University, on studying the drainage characteristics of several different hydraulic fills and barricade bricks\ud from various Australian mines. A new permeability cell was developed for measuring permeability and drainage\ud characteristics of barricade bricks in the laboratory, and JCU has developed and modified laboratory test procedures to assess the permeability of the various hydraulic fills under in-situ conditions. This paper describes some simple techniques used to quantify the flow characteristics of hydraulic fill and barricade bricks in simulated underground conditions. Several findings from this testing, pertinent to the current direction of the Australian mining industry are presented in this paper