Technology and application of fissures grouting in roof sandstone of heading roadway

Abstract

In order to effectively control the water flow from the overburden of the heading roadway, the method of drainage and depressurization combined with intermittent repeated grouting was adopted to transfrom the broken sandstone zone of the heading roadway. Through drilling long distance directional borehole above the roadway, the water-riched area can be drainaged. The layout of grouting boreholes on the plane and vertical was designed, and different grouting orifice devices are used for borehole with different water flow. Long distance directional boreholes were used for drainage grouting, and intermittent circular grouting was used for conventional borehole. The effect of fracture grouting in sandstone was verified by coring test and water inflow observation. It is illustrated by examples that the grouting effect of complete sandstone is poor, while the grouting effect of sandstone with developed fissures is good. The purpose of reducing water inflow of heading roadway and strengthening the broken surrounding rock can be realized by drainage water with borehole to reduce groundwater pressure in local area and sealing the fissures with grouting.

Keywords

• heading roadway
• sandstone fissures
• grouting reinforcement
• drainage and depressurization
• coring
• water disaster control