Study On The Effect Of Consolidation Process Of Filling Slurry On Mechanical Properties Of Deep Fractured Rock Mass

Taking the mining of the Macheng iron mine as a research background,the deep rock mass is collected and processed into parallel double-fractured rock specimens.Taking the model specimen filled with slurry and fractured rock mass as the research object,VIC-3D non-contact full-field strain measurement system and acoustic emission monitoring system are used to simultaneously monitor the failure process of the composite model specimens under different uniaxial compressions with different consolidation rates and different consolidation times.Combining theoretical analysis and field investigation results,the crack propagation and the change of mechanical strength of the composite model specimen are deduced.The results provide a theoretical reference for mechanical changes of surrounding rock in different periods caused by the immersion of mine slurry into rock mass,and provide safety and technical support for the underground workers.By comparing the stress-strain curves under uniaxial compression,it is found that the mechanical strength of the specimens in the same group changes "U" as the consolidation curing time shifts.Consolidation curing time is long enough,the peak intensity of the specimen must surpass the early maximum.From the x-direction strain cloud analysis of the specimen,it can be seen that the initiation angle of the specimen has a little influence on the consolidation time of the specimen,but the cracking angle of the specimen filled with the high concentration is generally smaller than that at the low concentration and the higher the concentration,close to the axial loading direction.From the point of view of fracture mechanism,the fracture modes in the early stage of the specimen are dominated by the cracked wing cracks generated at the tip of the fracture,whereas the latter fracture modes are different.That is,the specimen with high concentration fills,Wings-Longitudinal Cracks-Backwing Cracks,Low Concentration Filled specimens experienced reverse wing crack-reverse wing cracklongitudinal crack or reverse wing crack.The acoustic emission characteristics of the specimen during the entire failure process are studied from the aspects of ring counting and energy counting.The results show that the acoustic emission signal which is relatively obvious to the whole stress curve will be delayed and the corresponding acoustic emission signal intensity will be relatively weakened during the compaction phase with the extension of curing age.The ringing counting and energy counting a very strong AE signal is erupted before the peak,and the signal intensity is consistent with the change of the peak intensity of the specimen.