Backfill Mining Coal Strata Movement And Surface Subsidence Control Study

Paste backfilling mining is an effective approach to settle problem caused by coal miningunder buildings, railway and water bodies. Compared with other approaches, such as traditionalmining method and water-gravel-mixed filling,paste backfilling mining is high security, highrecovery ratio and environment friendly. The popularization and application of paste backfillingmining technology is fully consistent with the green coal mining which is greatly promoted inChina. The technology also can effectively solve the problems,such as“three unders” miningdistrict,heap and so on. Based on combining with physical simulation and numericalsimulation,the study analyze the law of the overlying strata movement and the surfacesubsidence.The mining method of the paste filling mining control of rock from the traditional, Becauseof the paste filling mining with filling body control the strata movement, so the overlying stratamovement and ground paste filling condition is different from the traditional method ofmining subsidence. Compared with other filling mining technique, the biggest advantage is thatfilling paste filling technology of goaf roof does not collapse. The subsidence phenomenon onlyin front of the working face roof and roof control area, the roof in mined out area because of thesupport from the filling body of subsidence control effectively. Therefore, filling mining stratacontrol is the key mobile control direct top and lower roof deformation. As long as thedeformation and failure of the roof and immediate roof has been effectively controlled, so toprotect the surface from damage to structures can be achieved.Based on combining with physical simulation,numerical simulation and sitemeasurement,the process and scope of the overlying strata movement were analyzed. Andmechanism of support action is described.The study use physical simulation and numerical simulation on different filling rations toreveal the law of the overlying strata movement,The results show that the roof stratum onlyoccur bending zone and minimal leakage zone,but not retarded caving. And it can significantlyreduce the strength of face strata.This paper introduces the paste filling system and the technological process of fillingdetailedly and explores the prediction model of surface subsidence. According to the predictionanalysis of subsidence coefficient,we found that subsidence coefficient can be controlled about0.16. Then it can ensure the security of the buildings in Nanwang village.Finally, combined with the specific situation in Xiaotun coal mine filling working face, theXiaotun mine working face filling mining ground subsidence after were observed and analyzed,at the same time, a detailed analysis of the mine Xiaotun filling mining cost structure, and the mine Xiaotun filling mining results are introduced.