Field test on dynamic disaster control by grouting below extremely thick igneous rock
Abstract：To safely extract the coal seam below the extremely thick igneous rock(ETIR) in II102 mining area of Haizi Mine,a technical measure of controlling dynamic disaster by grouting was proposed based on geological and mining conditions of the area.A numerical simulation with Universal Distinct Element Code(UDEC) was carried out to analyze the effect of grout injecting into the mined-out area on ETIR movement and stress concentration.The results show that stress concentration in the coal seam can be cased by the action of grouting mass’s bearing capacity;meanwhile,ETIR is less likely to break suddenly.A grouting scheme was put forward on the basis of simulation results.The field trail took 19 months to conduct the grouting of 6 boreholes in all.In the end,a total volume of dry flyash reached 267 320 m3.It suggested a filling ratio of 51.3% was gained and 70% of the mined-out area completely carried the overburden load.The advancement of conveyor roadway of II1026 working face resumed after the completion of grouting and the dynamic phenomenon didn’t occur again,demonstrating that grouting had conducted well and could ensure safe extraction of the following working face.
Keywords：extremely thick igneous rockdynamic disasterstress concentrationgroutingreducing disaster
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 1967-1974 )