In Situ Instrumentation of a Cemented Paste Backfilled Stope at George Fisher Mine

摘要

George Fisher Mine (GFM) is currently in the process of optimizing its backfilling placement and backfill barricade designs. Part of this process involves the installation of in situ and barricade instrumentation to monitor the loads being placed on the barricade and the response of the barricade to these loads. This paper presents the first installation at GFM, which involved total earth pressure cells and piezometers installed immediately upstream of the CPB barricade wall, and ShapeAccelArray instruments installed on the downstream side of the barricade. The results obtained showed that the pressures experienced by the barricade were lower than anticipated and significantly lower than GFM's current barricade design stress. The isotropic stress period (i.e. the backfill's fluid state) of approximately 5 hours was also shorter than expected. The ' instrumentation also measured some periods in which pressures increased even through the paste plant was not in operation. There also appears to be a positive correlation between pressure and temperature may indicate thermal expansion. Overall, this test is a first step in helping characterize GFM's in situ backfill behavior, providing encouragement that efficiencies can be found within the backfilling system. Further tests featuring more comprehensive installations are in preparation.