Materiały konferencyjne SEP 1993 - tom 2

Underground Exploitation School '93 performed at the first stage made it possible to advance 8 m over the no longer floating; 2 m of total 10 m of hardened rocks were left as the protection. At the second stage 12 electro-injectors were inserted into themassif spaced 0.62 - 0.75 m. Yolume of rock to be hardened was 20 m^ . The direct current was fed into the rock and the pump K-60 supplied to the anodes first 1.42 g/cnn^ NaSi solution, then 1.22 g/cm^ CaCl. The cathodes were vacuume treałed. Both solutions prior to supply were conditioned in the magnetic field produced by the plates placed on the polyethylene thick-wall tube section connected to the distributing collector from the capacitor part. The cations of the supplied electrolytes Ca^"*" end Mg^"^ effected by the magnetic field of a certain intensifi tend to decrease the hydration and to increase their volocity. The hardening solution passing through the magnetic field and as a result of the ions transfer, the e.m.f. appears in the electrolites which acts in the direction perpendicular to the field. Consecaently, the magnetic field makes active the physico-chemical processes in the rock in course of hardening. This sort of treatment intensifies the penitration of the electrolites into the rock with the homogeneous hardening as a result. To prevent the washing out of the upper set of electroinjectors was connected to the vacuume plant and the negative clamp of the d.c. source all the way. The remaining injectors, the needed quantity of reagents having been pumped, were cut off the vacuume plant. The polarity was periodically changed to maintain the process of hardening at the active regime. At the same time were changed this values of voltage, electricity and electrolytes consumption, vacuume intensity produced by the plant on the cathodes. The drift driving showed the statisfactory stability of the treated rock. Its slrength limit for the single axis compression was 0.5-1 MPa. To do the job it was reąuired to use 60 m of 40-45mm tubes, 2.8 t NaSi, 0.8 t CaCl, around 12.8 thousand KW • hrs of energy. As a result of the introduction of the techniąue described the stability of the dispersed side rocks was perfected which provided for the safety of the works up to the ventilation drill hole. 158 Tom II