Study On Mechanical Properties Of High Concentration Full Tailings Cemented Backfill

With the continuous increase of solid waste resources,the state has new requirements for the construction of “green mines”.How to rationally use solid waste resources has become an urgent problem for major mining enterprises.The cement filling and filling technology is an effective method for reusing the solid waste resources by filling the mining area by using solid waste resources.However,with the gradual deepening of the mining,the strength of the filling body has higher requirements.Therefore,studying the proportioning scheme of filling slurry is the core issue to ensure the effect of filling treatment and control production cost.In this paper,the slab uniaxial compressive strength test,shear strength test and triaxial compression test are carried out to propose the filling ratio preparation scheme of the filling body which meets the mining requirements,and the filling constitutive model is established to match the filling body with the rock mass.Analytical and reliability analysis was carried out for theoretical verification,supplemented by numerical simulation and on-site monitoring data analysis.The strength and mechanical effects of the full tailings cemented backfill were studied.The contents and conclusions are as follows:Uniaxial compressive strength test,shear strength test and triaxial compression test of full tailings cemented backfill under different slurry concentrations,different sand ash ratios and different curing time conditions,combined with test results and actual production requirements and transportable Factors such as sex,finally concluded that the filling ratio can be filled with a slurry concentration of 70% and a sand ash ratio of 1:6.By establishing the constitutive model of the filling body,combined with the evolution of the damage process of the filling body,the reasonable matching of the energy of the filling body and the surrounding rock,and the reliability analysis of the mechanical model of the filling body under the surrounding rock,the theoretical strength required for the filling body is The test results were compared and analyzed,and the experimental optimal solution was basically consistent with the theoretical calculation results.Therefore,the optimal parameters obtained by the laboratory can be used as a reference for the actual filling operation.Based on the simulation analysis of the effect before and after filling in the goaf of the ore body,the comprehensive simulation was carried out by using FLAC3 D.The 2-2 empty area in the middle of-410 was taken as the main object of the study,and the mining and filling stability study was carried out to obtain the ore body goaf.Before the filling of the area,the stability of the roof of the empty area is better,while the surrounding rock of the empty area is relativelyslightly poor.After the goaf is filled,the filling body plays a role,the stress concentration at the top of the empty area is alleviated,the tensile stress of the surrounding rock of the empty side is reduced,the tensile stress of some areas disappears,and the surrounding rock movement degree of each area around the empty area There has been a downward trend.It can be obtained that the ratio of the cement filling scheme and the strength of the filling body satisfy the criteria for the treatment of the empty area.The secondary monitoring of surrounding rock and the monitoring of surface deformation are taken as the main monitoring contents,and the results of the inspection before and after filling in the goaf are analyzed.From the trend of the stress-time image,the disturbance of the stope and the stress redistribution after the filling operation are compared,and combined with the displacement data of the surface deformation monitoring,the results show that the monitoring data is basically consistent with the numerical simulation results.It is fully confirmed that the filling and proportioning scheme obtained by the laboratory is feasible,and the purpose of verifying that the filling operation has reached the treatment empty area is achieved,and the safety of subsequent operations can be guaranteed.The paper has 48 figures,26 tables,and 60 references.