Grants and Contributions:

Grant or Award spanning more than one fiscal year (2017-2018 to 2021-2022).

Due to a combination of mining methods used to extract the mineral deposits and the tectonic stress regime unique to the kimberlite pipes the Canadian underground diamond mines are currently experiencing significant ground movements and in some instances some mines are reporting severe ground failures at their underground openings. These ground failures are not only hazards to the safety of mining employees but also reduce the extraction efficiency of the mineral and revenues at these mines. The high cost of underground operations and the low economy make the situation even worse.x000D
The goal of this proposal is to develop an integrated approach in increasing extraction efficiently. Firstly, ax000D
systematic characterization of the host rock and cemented rock fill (CRF) will be conducted through a series of comprehensive laboratory and field in-situ investigations. After that, a stress-strain-volume change constitutive law will be derived from these characterizations for both rock mass and CRF in numeric modeling. Moreover, an assessment of the stability of underground workings will be implemented after pillar recoveries. At the end, ground performances will be monitored and data will go back to the prediction model as feedback and adjustments. As a result, a practical design guideline will be prepared to assist the pillar recovery for Diavik and other underground Canadian diamond mines.