Mechanical Parameters Estimation Of Rock Mass And Evaluation Of Surrounding Rock Mass Stability Of Roadway

Occurrence, status and so on of the structural surface included in the rock masses, in particular the mechanical properties plays a decisive impact on the rock shapes. Because of the existence of the structural surface, it's unreasonable to recognize the surrounding rock masses as homogeneous and isotropic intact rock while making assessment of rock mass stability. The affection of structural surface on the rock mass strength should be considered and the strength of fractured rock mass should also be studied in-depth. With the rapid development of computer technology, numerical simulation has become a powerful tool to solve geological and mining problems and it has an advantage that other research methods can not match while conducting evaluation of fractured surrounding rock mass stability.The site geological and hydrogeological conditions of Hongliulin Coal Mine was investigated firstly, and structural features of surrounding rock mass of roadway was summaried. Then the physical characteristics of surrounding rock mass of roadway was studied and the value method of mechanical parameters of jointed rock mass was given. The physical parameters of surrounding rock mass of roadway in 25201 working place was estimated using Hoek-Brown empirical strength criterion. Based on this, the stability of fractured surrounding rock mass of roadway in 25201 working place was analized beforce and after supporting using large discrete element software UDEC, and the simulation results were made a system analysis, and the conclusions were as follow:After the roadway was excavated and before the supporting was done, the displacement of surrounding rock is mainly occurred in the roof of roadway for vertical direction, and vertical direction of surrounding rock at the top of the roadway occurred displacement deformation, and then the surrounding rock of roadway roof was raised collapse damage. Before supporing, the displacement of surrounding rock of the roadway roof is abvious, and part of the surrounding rock occurred collapse phenomenon, also the extent and scale of displacement of the surrounding rock of roadway wall is small after excavation. This can reflect that after the roadway was excavated, the dispalcemnet of surrounding rock and the defoemation damage caused by deformation are mainly occurred in the roadway roof in vertical direction. After supporting by using anchor bolt, the displacement scale was reduced to a great degree. The surrounding rock displacement of roadway roof is in the static displacement stage, and the roof is more stable. The bolting can effectively strengthen the roof and ensure the stability off surrounding rock mass.