PROCESS OF SUPPORT OF MINE WORKINGS ( ALTERNATIVE APPROACHES ) Russian patent published in 2000 - IPC

FIELD: mining industry, erection of supports in mine workings. SUBSTANCE: process of support of mine working includes installation of sections of traveling forms in face and laying of concrete mix in space behind forms. Working is supported simultaneously with cutting cycle and concrete mix is placed in layers. First layer is placed from above to bottom of floor, second layer is laid after hardening of first layer and corresponding movement of sections of traveling forms. Concrete mix including, kg/cu m: cement 400-500, sand 600-750, crushed stone 900-1100; mineral addition 80- 100 and water 200-250 l is used in composition of first and second layers. Mineral addition contains, per cent by mass: gypsum 15-85, dolomite 0-5, microsilica 0-30, volcanic rock being the balance. Reinforcement cage is installed prior to placement of first layer of concrete mix. Inclined drainage holes along outline of working at distance of 1.0-1.2 m one form another are drilled to support mine working in flooded rocks before placement of concrete mix, holes are filled with cement compound carrying cement and 15-25 per cent by mass of addition containing, per cent by mass: gypsum 15-35, dolomite 0-5, microsilica 0-30 , volcanic rock being the balance. In correspondence with alternative approach tubing is installed in addition after hardening of concrete mix of first layer and removal of forms and space formed between tubing and first layer of concrete mix is filled with second layer of concrete mix laid from bottom upwards. EFFECT: increased water impenetrability of concrete support, possibility of cutting and running of mine working in flooded rocks. 5 cl