Research On Dynamic Crushing Energy Consumption Law Of Surrounding Rock In Deep Roadway Of Dahongshan Copper Mine

With the development of mineral resources in the deep,the rock mechanics environment in which the rock mass is located has changed,and the safety and stability of deep roadways and efficient excavation are facing serious challenges.In order to study the law between energy transfer and fragmentation fractal of deep roadway surrounding rock under dynamic load,this article relies on the horizontal subject"Research on Key Technology of Blasting Residue Control in Roadway Excavation",one of the research contents "Research on Dynamic Characteristics of Roadway Surrounding Rock",taking Dahongshan roadway surrounding rock dolomite marble and garnet biotite schist as the research objects,according to the results of in-situ stress monitoring,with the help of the SHPB test device,the conventional uniaxial dynamic load test and the three-dimensional combined dynamic and static load test are carried out to study the dolomite marble.The energy transfer law and fragmentation fractal law of rock and garnet biotite schist,and the fractal law of energy and fragmentation under different loading conditions are explored,and it is found that the dolomite marble and garnet biotite schist of Dahongshan roadway have similar laws.The main conclusions are as follows:The conventional uniaxial load and the three-dimensional dynamic and static combination are the same static load(dolomite marble ?z=30MPa,?w=14Mpa,garnet biotite schist ?z=40MPa,?w=20Mpa.)Under different dynamic loads,With the increase of strain rate,the reflected energy,transmitted energy and absorption energy of rock increase,the proportion of energy reflection increases,the proportion of energy transmission and energy absorption decreases,and the peak stress of rock increases.After screening the impact crushed rock,it is found that the strain rate increases,the average particle size characteristic value of rock crushing decreases,and the fractal dimension decreases.Exploring the fractal relationship between energy and lumpiness,we get:There is a positive correlation between the fractal dimension and the logarithm of the incident energy density,The specific relationship is:The specific relationship is:Dolomite marble under conventional uniaxial load D=1.961g(WI/V)+1.50;Pomegranate biotite schist D=1.911g(WI/V)+1.48;Three-dimensional fixed static load(dolomite marble ?z=30MPa,?w=14Mpa,garnet biotite schist ?z=40MPa,?w=20Mpa.)and different dynamic load of dolomite marble D=5.791g(WI/V)-3.02;Pomegranate biotite schist D=3.611g(WI/V)-0.79.Three-dimensional dynamic and static combined fixed dynamic load(impact air pressure 1.6MPa).Under different static loads,with the increase of buried depth(axial-confining pressure),the proportion of reflected energy and absorbed energy of rock decreases,and the proportion of transmitted energy increases.The peak stress increases.The fractal law of fracture fragmentation is:the characteristic value of the average particle size of rock fracture increases with the increase of buried depth(axial-confining pressure),and the fractal dimension decreases with the increase of buried depth(axial-confining pressure).It shows that under the same blasting energy,as the buried depth(axial-confining pressure)increases,the energy absorbed by the rock decreases and the rock fragmentation increases.