METHOD FOR DRIVING AND SUPPORT OF MINE WORKINGS AND FRAME SUPPORT FOR ITS REALIZATION Russian patent published in 1994 - IPC

FIELD: mining. SUBSTANCE: method includes formation of trapezoidal face, installation in working of trapezoidal support separated into two levels by installing middle bracing members 6 and 7 connected with props by means of caps 10 and 11. Upper part of working face is arranged under most strong rock layer. Limit span of said layer is determined during driving of working, and accuracy of determination is checked by observation for minimum 15 days. Width of upper part of face is equal 4/5-5/6 of limit span, and height of working is taken to exceed length of medium line of trapezoidal face minimum by two times. Roofing, middle bracing member and props are connected with lap joint by yielding units having frictional layer. Value of overlap of roofing is larger than 2/3 of limit span of rock overlying layer. Roofing may be straight or curved. Prop yielding units are installed over length equalling or higher than thickness of most weak parts of rocks. EFFECT: higher efficiency of working support due to utilization of supporting properties of rock mass depending on determination of limit span. 6 cl, 2 dwg