Experimental Study Of Multi-layer Grouting Subsidence Area Recovery And Controlling Technology

In recent years,the mining damage and environment problem caused by underground resources mining increasingly prominent,"the green mining" has become an important direction for the sustainable development of coal industry.Surface subsidence caused by coal mining,not only destroy the surface ecological environment,damage the surface buildings and structures,but also associate with serious safe problems.It is imminent to solve this problem.This paper puts forward a multi-layer grouting method to recovery the subsidence area.The method reference for a method called "hydraulic fracturing",using the high-water material‘s character of strong flow ability,the adjustable initial curdle time,and Three-dimensional incompressible.Drilling holes into shallow bedrock on the subsidence surface and grouting high-water material slurry into bending subsidence zone grouting layer(weak rock or weak interlayer),using the high pressure pump make the material slurry grouting layer produce high pressure,supporting the overlying subsidence strata,recover the subsidence and deformation of the surface.The regional subsidence area was achieved recovery by reasonable arrangement of borehole spacing,achieved to protect the buildings,structures and the ground surface ecological environment.This paper,concluded the determination basis of grouting layer through theoretical analysis;Reference abscission layer grouting method and hydraulic fracturing set up grouting subsidence area surface recovery mechanics model;It can be concluded Through the experiment that under the condition of different ratio of the high-water materials initial curdle time,fluidity and compressive strength,etc;By using the three-dimensional similar material simulation to analyst the feasibility and rationality of the multi-layer grouting method that recover the subsidence area;Using the two-dimensional similar material simulation test and computer numerical simulation experiment to analyst the grouting spacing and depth to the influence relationship of the subsidence area surface recovery.The optimum drilling density of subsidence area regional recovery was obtained,providing theoretical basis and research methods for field experiment and application in the future.