Study On Damage Evolution Law Of Surrounding Rock In Stope With Two-Way Load Filling

Filling mining method is one of the three mining methods widely used in domestic mines.The surrounding rock of the actual filling stope is in a complex stress environment.In order to study the fracture evolution law of the surrounding rock of the filling stope.Two-way loading tests were carried out on stope and rock combination model.Non-contact fullfield strain gauge,acoustic emission monitor and SLR camera were used to monitor the damage of surrounding rock in filling stope during loading.Based on laboratory tests,the stress-strain relationship of the combination model,the axial strain field diagram,the change of acoustic emission event rate with time,acoustic emission energy,acoustic emission registration point and the fractal characteristics based on the change of registration point in different time periods were studied.1)By analyzing the stress-strain curve and axial strain cloud diagram of the surrounding rock combination model of different lime-sand ratio and different lateral stress filling stope,the peak value of the model becomes larger,the corresponding strain value of the stress peak becomes larger.The stress-strain curve of the model shows strain rebound in the plastic stage.2)Based on acoustic emission monitoring results,acoustic emission laws of loading failure of surrounding rocks with different lime-sand ratios and lateral stress filling were studied.The time relation curves of ae event rate and energy of the model under different lime-sand ratio and lateral stress were obtained.3)The spatial distribution of acoustic emission source registration points can well represent the damaged parts.The locus distribution law of acoustic emission source has fractal characteristics.The spatial distribution of locus of acoustic emission source with different loading conditions and lime-sand ratio model is calculated by fractal dimension and cumulative fractal dimension at different stages.The phase dimension shows a downward trend and the cumulative dimension shows an upward trend4)The damage model established can well reflect the damage changes in each loading stage of the model with the accumulative count of acoustic emission source registration point as the variable.Figure38;Table4;Reference 60...