Research On Multi-field Coupling Model Of Composite Coal-rock In Deformation And Fracture Under Load

Coal-rock dynamic disasters are coal and rock under the action of external stress happened in a short time.The phenomenon of dynamic effect and the consequence of disaster is an extremely complex dynamic phenomenon.EME,infrared radiation of coal-rock deformation and failure process,can effectively predict rock bursts,coal and gas outburst and other dynamic disaster.It realize the dynamic forecast of non-contact continuous.The main findings are as follows:This paper study on the stress-electricity-thermal multi-field coupling model of composite coal-rock in deformation and fracture under load.Develop a new EME acquisition system independently for test electromagnetic emission.Make a test plan for the project.Analyse the relations among EME intensity,EME pulse count,and stress.The analysis finds that the three have high coupling.Analyse the relationsbetween EME intensity and EME pulse.Their linear correlation coefficients are above 0.9.Analyse the relationsbetween EME intensity and stress.Their linear correlation coefficients are above 0.8.Analyse the relationsbetween infrared raditions and stress.They are moving in the same direction.Analyse the relationsbetween infrared-radiated temperature and stress of coal,infrared-radiated temperature and strain of coal,infrared-radiated temperature and stress of rock,infrared-radiated temperature and strain of rock.Four linear correlation coefficients are above 0.9.The compound injury factor was proposed.The stress-electricity-thermal coupling model of the composite coal-rock are estabilished.Validation of the model.The results showed that the precision of the new model is improved than before.The simulation study of stress-electricity coupling field and stress-thermal coupling field by ANSYS finite element software.The stress-electricity coupling field show that there is no contribution on densificationstage.The relationship between stress and induced charge is linear on elastic stage and plastic stage.The stress--thermal coupling field reflects the change of temperature of the friction in the fissures,and the change of temperature is positively correlated with the change of stress.The simulation results are consistent with the experimental results.Thesis research results to further reveal the mechanism of coal and gas outburst and other dynamic disaster evolution,perfect the coal and gas prediction method of coal and rock dynamic disasters and guarantee coal mine safety in production is of important theoretical significance and practical application value.