Study On The Technology Of Anchorage Supporting In Special Soft Coal Roadway

China is the largest coal consumer in the world and the demand is still increasing. In order to meet the increasing demand of coal, most orefield have entered into the exploitation of deep mine beds. When exploitation surpass the critical depth, the driving and supporting coal roadway appears a series of large deformation and failure phenomenon, which includes difficulty in forming roadway, roof sink, walls shrink and the floor heave. Therefore, deep coal roadway supporting has become a key technical problem, which greatly affects the normal excavation and safe production, after entering into the critical depth. The property of No.2 Coal Mine in Liangbei coal mine is very soft and coefficient of hardness f=0.15-0.25. Therefore, No.2 Coal Mine belongs to extra-soft coal seam. Roadway supporting difficult coefficient is 1.8. This thesis launched a series of research on the technology of anchorage supporting aiming at solving the problem of extra-soft coal roadway in the complex problems in Liangbei coalmine.First of all, the investigation should be carried out to analyse the geological mechanics environment in Liangbei mine. It can determine formation lithology, geological structure, groundwater and in-situ stress in project area. The rock samples are selected in-site and then made into the rock models to measure their physical and mechanical properties. After the analysis, the rock mechanics parameters can be confirmed and applied to assure rock engineering geological characteristics in project area combining with the geological mechanics environment.Deformation and failure characteristics of coal roadway are learned about through the field observation and monitoring. Bearing capacity of I-beam and weakening of coal floor are analysed in view of the deformation and failure characteristics of roadway. The reason of deformation and failure is introduced from the standpoint of rock properties, in-situ stress and supporting form. Geological and engineering mechanical model is established on the basis of geological and supporting condition and the coal roadway destroy process was recurrence.The critical depth and supporting difficult coefficient for Liangbei coal mine are determined according to the definition of soft rock. Influence factor of deformation mechanics mechanism is analysed. Deformation mechanics mechanism of experimental roadway is determined and the transform countermeasure is constituted.Taking off from bolt-mesh-cable coupling support principle, optimal design of bolt-mesh-cable coupling support for roof and floor is operated by FLAC3D. Four floor supporting schemes are put forward using the bolting and grouting technology. Roof and side bolt-mesh-cable and corner anchor grouting combined support is adopted in the testing roadway and the results demonstrate that the scheme adopted in the testing roadway could control roadway deformation effectively.