At Outokumpu Chrome Oy Kemi chromite Mine, Finland rock mechanical problems caused by rock stress occur in unfavorable geotechnical conditions. Maximum rock movements are about 10 to 20 cm. This has led the need to repair the rock support and re-excavation.
A research program concerning tunneling in difficult rock stress conditions has been started at the Kemi mine.
The results from the rock mechanical simulations are compared to the measured displacements. Input data for the rock mechanical simulations are rock stress measurements, Q' classification from drill holes and drifts, uniaxial and triaxial strength measurements and point load tests. Part of the project is to determine the conversion factor and it's deviation for point load index 150 to the uniaxial compressive strength for main rock types in Kemi mine.
The project goal is to develop a support design system that is based on Eurocode 7. Geotechnical design (EN 1997–1), Observational method.
At Outokumpu Chrome Oy Kemi chromite Mine, Finland rock mechanical problems caused by rock stress occur in unfavorable geotechnical conditions. These areas higher rock stress field are caused by the nearby slopes and large-scale block movements. Maximum rock movements are about 10 to 20 cm. This has led the need to repair rock support and re-excavation.
Rock support failures regard extra work safety actions, more working time, stops traffic on repair work area and means extra costs.
A research program concerning tunneling in difficult rock stress conditions has been started at the Kemi mine. The project goal is to develop a support design system that is based on Eurocode 7. Geotechnical design (EN 1997–1), Observational method.
