Static Rock Breaking Law And Engineering Application Of Roadway Floor In Sima Mine

The static breaking agent exerts pressure on the inner surface of the broken object at a slow and controllable speed during the rock breaking process.This process has no noise,vibration and gas,etc.,so it has the advantages of safety and environmental protection.Static crushing agent has irreplaceable application value in the fields of stone cutting and urban concrete construction demolition.At present,the material is gradually applied to coal mine rock breaking projects such as cutting hard roof and controlling roadway floor heave.However,due to the limitation of the material characteristics and the special underground environment,the traditional static crushing agent takes a long time in the process of rock breaking,which is difficult to meet the needs of coal mine underground mining engineering and restricts the wide application of the technology in coal mines.This thesis takes Sima Coal Mine CT1101 air lane 1# water tank and 1218 tail lane floor rock breaking as the engineering background,adopts various methods such as theoretical analysis,laboratory test,numerical simulation,etc.,to further explore the application of static rock breaking technology in the field of mining engineering.The main research results are as follows:(1)Based on the principle of static crushing hydration reaction,the expansion mechanism of static crushing agent was explored,the static rock breaking mechanical model was constructed,the influencing factors of static rock breaking were analyzed,and the rock cracking mechanism and crack propagation law under single hole and porous conditions of static crushing agent were studied.(2)Through a series of hydration reaction tests,the volume expansion rate of static crushing agent under different water-agent ratios,the relationship between reaction temperature and time during hydration reaction,the expansion pressure growth curve of each type of static crushing agent at its appropriate temperature and the expansion pressure growth curve of the same type of static crushing agent at different ambient temperatures are summarized,which provides data support for the selection of numerical simulation parameters.(3)Through the uniaxial compression test of 50 mm × 100 mm standard specimens under different water-cement ratios,the material ratio of indoor static rock breaking test model was determined.The static rock breaking test of indoor 600 mm × 600 mm ×600mm large-scale specimens was carried out.Combined with numerical simulation,the difference of fracture of cement specimens under different drilling arrangements was compared and analyzed.The macroscopic fracture effect and crack development evolution law of specimens with or without constraints were revealed,and the crack penetration morphology of specimens with different hole arrangement modes was obtained,which provided a basis for the design of on-site rock breaking drilling.(4)Based on the engineering background of 1 # water sump and 1218 tail roadway floor rock breaking in CT1101 air roadway,the optimal static rock breaking construction scheme and technical parameters are designed.The effective rock breaking time on site is between 6.5-7 hours,which is 30-35 % shorter than the traditional static rock breaking time.The rock fragmentation meets the construction quality requirements,which lays a foundation for the popularization and application of static rock breaking technology in coal mining engineering.