Study On Flow Law Of Grout Diffusion In Fractured Rock

With the rapid development of economy, China has a sharp increase in demandfor coal resources. The development of coal industry in the "Twelfth Five Year Plan"also clearly pointed out that, the position of coal as the main energy will not change inthe future for a long time. China’s coal mines were under a growing threat from theOrdovician limestone. If the problem that safety mining above confined aquifer andliberation of deep coal reserves couldn’t be solved in time, some of mine willreduction of output and even forced to shut down. In recent years, throughunremitting efforts of vast mine hydrogeological workers, grouting technology as themost commonly used method of mine water disaster control has achieved good results,and grouting theory also has great development. But at present, there are alsoproblems, such as theoretical study is far behind the technology experience, nomathematical model accords with actual, laboratory testing system is relatively simple,grouting design often cannot cover all the influence factors, the difference ofcalculated results and test is very big. So, research on multiple crack grouting slurrydiffusion is much-needed.This article embarks from the grouting process, the effect of slurry diffusionfactors, comparison of the influence of various factors, the slurry dominant orientationfeature under different factor were studied by the method of theoretical analysis,laboratory test and field test. Some useful conclusion were drawn.(1) From the summary of diffusion factor from the target and process of fracturedrock grouting. Factors influencing the grout diffusion is mainly divided into slurryproperties, fracture characteristics, grouting technology and other factors. Eachfactor’s mechanism is described in detail.(2) Grout diffusion dominant orientation was defined, the multiple crack groutdiffusion test system was designed and laboratory physical modelling experimentswas carried out. Test solution includes viscosity, aperture, angle, opening gradient,tortuosity, roughness and grouting pressure. Results of the experiments has verifiedthe hypothesis and achieved the desired results.(3) The impulse type grouting technology was put forward through theoreticalanalysis and physical test results. Impact force produced by periodic pressure forcedthe cleavage of dead end of fractured rock mass and small internal fracture, formed new seepage channel. The industrial test carried out in Caocun coal mine main shaftwater segment. Surrounding rock fracture distribution characteristics were analyzedthrough on-site drilling. According to this, layout of grouting holes and groutingpressure were chosen. The grout diffusion effect is good, the water quantity wascontrolled, which have verified the conclusions of the study. This technology has acertain theory significance and application value.