Proposed systematic support rule under regulation 108 of Coal Mines regulation 1957 for the development workings of No. VII(Bottom) seam at Bararee Colliery M/s BCCL
1. General
1.1 The rule shall be applicable to all workings in the development district of VII(Bottom) seam.
1.2 The RMR of the roof rock as determined by CMPDIL as per their report no. _________ is 45.03.
1.3 Wherever there is change in the roof condition of VII(B) seam a freshly study of RMR shall be made and fresh SSR shall be formed and sent to Directorate for approval.
2. Support of every development workings within 10m of the face.
2.1 The roof shall be supported by full grouted roof bolts with quick setting grout installed maximum interval of 0.8 m in the same row. Such that the distance between bolts and pillars side shall not more than 0.5m.
2.2 The spacing between the two rows shall not be more than 0.9 m however the distance of the first row of bolts from the face shall not be more than 0.5 m.
2.3 The bolts adjacent to the pillar shall be suitably inclined from horizontal towards the pillar whereas the remaining bolts shall be vertical.
2.4 Before engaging persons to drill holes for roof bolts temporary support shall be erected at 1.2 mtr. Interval to ensure safety of supported persons.
3. Support of junction including these immediately out bye of development face.
3.1 Junction shall be supported by rows of bolts as specified for those of development workings within 10m of the face. So however the distance between two rows of bolt at every edge of the junction shall be reduced to 0.76m and the spacing between the two bolts in the same to 0.76m
4. Support of ledged sides, overhangs and slips etc.
4.1 All ledges in the roof shall be supported by at least two cross bar set on cogs.
4.2 Wherever the sides of pillar have tendency to spall, these shall be supported by the rows. (minimum) of roof bolts at spacing of 1.0m. The distance between rows of bolts not exceeding 1.2m
4.3 All overhangs which cannot be dressed shall be kept supported by inclined stay props at intervals not exceeding 1.0m.
4.4 All faults, slips, brakes and other geological disturbances in the roof shall be supported by cogs at 2.4 m intervals on the either sides of such disturbances and with w-strap across at interval not exceeding 1.2m.
5. General guidance of roof bolt design.
5.1 Roof