Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
313062 | Tunnelling and Underground Space Technology | 2014 | 7 Pages |
•The mine improvement of rock mass rating (M-IRMR) evaluation system was put forward which suit for undersea deposit.•The rating values of rock compressive strength, rock quality index, joint spacing, and ground stress were modified.•The computing method of rock strength index weakening by seawater and geothermal was presented.•Blasting vibration and mining exposed areas effects on the quality of rock masse were considered.
The mine improvement of rock mass rating (M-IRMR) evaluation method was put forward based on the existing theory of the rock quality classification and the stability evaluation in the undersea deposit of Sanshandao Gold Mine, China. The M-IRMR evaluation method includes 9 evaluation indexes which are rock compressive strength, rock quality index RQD, joint spacing, joint state, groundwater state, joint direction, ground stress, blasting vibration, and exposed area, respectively. During the evaluation process, according to the special features of the undersea deposit, the rock mass rating (RMR) method was used as the foundation, and the four geological parameters (i.e., rock compressive strength, rock quality index, joint spacing, and ground stress) were modified. The computing methods of the two engineering factors (blasting vibration and exposed area) were presented. The M-IRMR rock quality classification and stability evaluation method was applied in the level of −420 to −690 m in the undersea deposit of Sanshandao Gold Mine and the classification results were consistent with the actual situations, which can provide a scientific basis for choosing the suitable mining method and stope support system of the undersea deposit.