Stability Research On Surrounding Rock With Goaf Filling In Extremely Steep Coal Seam

The stability condition of stope surrounding rock is poor led to control with difficulites after mining in extremely steep coal seam, pressure of stope is not periodic, air and water from surface flow into goaf induced coal sponta neous combustion and debris flow in stope. Research on goaf filling to control surrounding rock stability in extremely steep coal seam was proposed, achieve the relative results of safe mining in stope.By rock mechanics experiment on rock and coal from site was applied to obtain their mechanics parameters, which provides scientific evidence for constructing physical simulation experiment model and numerical simulation experiment model reasonably; By physical simulation experiment with AE and total station to monitor AE signal from surrounding rock in stope and sedimentation value of overlying strata of pior and post filling. The results showed that: the cumulative energy, cumulative event, event variance ratio and energy variance ratio with filling was less than the cumulative energy, cumulative event, event variance ratio and energy variance ratio with no filling. Value of overlying strata of goaf filling in stope was less than the value of overlying strata with no filling, goaf filling have a good effect on controlling surrounding rock stability in extremely steep coal seam; According to numerical simulation experiment, simulate distribution character of stress and deformation of surrounding rock with pior and post filling in extremely steep coal seam, the results showed that: the stress and deformation after goaf filling was uniform distribution compare with the ones before filling; GPR was applied to probe the compaction rate site. It need refilling if there is remarkable gap and water in goaf.Goaf filling in steep inclined coal seam have good effect to eliminate the safety precautions of stope caused by the poor stability of surrounding rock, it was solved the sharp contradiction between mining and safety. The research provides a reference for goaf filling to control surrounding rock stability in extremely steep coal seam and other dipping angle seam.