Drainage behaviour of three-dimensional hydraulic fill stopes: a sensitivity analysis

Abstract

Recent barricade failures in underground hydraulic fill mines in Australia and overseas, have resulted in significant economic loss and on a number of occasions, loss of lives. As a result, there is an urgent need in the mining industry for proper understanding of underground filling practices and in particular the use of hydraulic filling. Using analytical solutions developed for flow through three-dimensional hydraulic fill stopes, an EXCEL model was developed 'to accurately and efficiently model the drainage behaviour in three-dimensional stopes. The model simulates the complete filling and draining of the stopes and was verified using the three-dimensional finite difference program and results showed excellent agreement. This paper investigates the variation and sensitivity in drainage behaviour and pore water pressure measurements with, the fill properties of a three-dimensional hydraulic fill stope. The model studied in this paper assumes a simple drain geometry, with a square based stope and single square drain outlet located at the centre of the stope face.