Study On Mechanics Model Construction And Fracture Mechanism Of Filling Body-pillar System

During the filling and mining process,the filling body and the supporting pillar are jointly carried so as to prevent the surface from sinking and ensure the safety of the surface buildings at the same time.In this paper,in order to explore the action mechanism of underground mine fillings and ore pillars,the filling-pillar model has established,and we systematically conducted a series of studies on backfill-pillar mechanical systems using theoretical analysis,physical test analysis,and numerical simulation..As the strength of the pillar changes,the experiment revealed the bearing behavior and macro-scale failure evolution of the filler-pillar system.The works content is as follows:1)The mechanics model of filling-pillar system is established by using the theory of semi-inverse solution mechanics in elasticity.The horizontal stress and shear stress variation of the model with different widths or heights were revealed.2)By carrying out the experiment of filling-pillar mechanics system,we conclude that the lateral supporting effect of the filling body on the sandstone makes the sandstone greatly enhance its bearing capacity and can have a better performance than sandstone large carrying capacity.In the early loading model,the acoustic emission signals of the pillar(granite)filling body with a relatively large hardness are weaker and the bearing effects are weaker,and pillar is the main carrier of the model.With the increase of strain,pillar with smaller stiffness(sandstone)is more obvious in the process of failure.Therefore,it is concluded that as the rigidity of the pillars increases,the support effect of the pillars on the pillars gradually weakens.3)When we numerically simulate the backfill-pillar system model,it is very obvious that the acoustic emission pull signal is generated at the system contact surface.As the rigidity of rock columns increases,the bearing function of rock columns becomes more and more obvious.Horizontal and shear stress changes with the theoretical trend of deduction.