Numerical Simulation Of Broken Rocks

With the development of society,underground engineering has continued to extend to depth and breadth,and the problem of rock breaking in engineering has been mentioned as a prominent position.Aiming at the problem of rock breaking,the interaction between cutter teeth and rock is analyzed from both theoretical and numerical simulations.The interaction between the teeth and the rock is a contact problem.The actual rock is regarded as a semi-infinite elastic body,and the mechanical model of the interaction between the tooth and the rock is established.The elastic mechanics analysis method is used to derive the rock under the action of the flat end indenter and the spherical indenter by using the solution of the Boussinesq’s problem.The stress field and displacement field are simulated.Based on the ABAQUS software,the interaction between the two types of teeth and rock is simulated.The stress field and displacement field of the rock are obtained,and the theoretical results are compared with the simulation results.Then,based on this,the plastic parameters are added to the material properties of the model,and the ultimate load and the equivalent plastic strain cloud of the rock mass under the action of the flat end indenter and the spherical indenter are obtained.The calculation shows that the flat end indenter Under the action of rock,it is more likely to cause large-area breakage,and the spherical indenter is more likely to invade the rock.The three-dimensional solid element is used to calculate the rock-breaking model of the cylindrical tooth hob.The numerical calculation results of the hob force are compared with the theoretical calculation results.The analysis shows that the two agree well when calculating the average thrust.The simulation of the optimal tool spacing for a certain type of granite was carried out on a 320-tooth diameter toothed hob with a diameter of 320 mm.According to the analysis,as the pitch of the knife increases,the specific energy decreases first.When the distance between the hobs is about 50 mm,the specific energy is the smallest.Subsequently,Continue to increase the hob spacing,the specific energy value increases with the increase of the knife spacing.When the knife pitch is greater than80 mm,the obtained specific energy value is substantially stable.It can be considered that there is an optimum knife spacing of a cylindrical toothed hob between 40 mm and 60 mm.