Applied study on water drainage and permeability controlled grouting technology and water inflow treatment

in order to solve the grouting and water sealing techrical problem of the loose and broken surounding rock with the high pressuized water infow in theshallow stata in a coal mine a water drainage ,permeability controlld grouting technology was provided. ith the tests.a study was conducted on the c- CT grout performances ,the grouting pressure affected to the falure of the surounding rock,.the grout fowing within the grout peline,the comecion between the wae inflow and control area,he infuence when the water drainage borehole closed and others.The study resuits showed tht under the condition of the deep waer drainage.the folowingparameters applied to seal the igh pressuized water infiow within the loose and broken surounding rock of the shallov strata were sae and efe ctve.Under the condition of the ambient temperature the P.042.5R.cement would be aplild,the density of the cement grout would be about1.5 0 g i cn3( a water and cenent rato woud be 1 : 1).the density of the GT grout would be 1.20 ~ 1.5.0 gicem.the volume ratio could be contolled at 1: 1~ 3 ∶ 1.the retarder should be added propery under the high temperature environment in the underground mine.Theintal seting timeof the C- GT grout shoud be about 5 seconds longer than the comnected ime of th racer and the grouting pressure should be controlled belcw 2. 5 MRPa. When the total area of the drainage borehole was closed to the intern al diameter areaof the groutingpipeline,the grout flowing would be best and could be the highest controlled velocity during the grouting period.