Infrared Radiation Response Mechanism And Quantitative Characterization During Damage Evolution Of Loading Coal And Rock

Damage evolution of coal and rock under the influence of mining is one of important content in strata control researching in mining,which is also a basic theory and common problem needs to be broken through in the study of dynamic disasters such as mine water inrush and rock burst that seriously affect the safety production in coal mines.The study found that the damage evolution process inside the loading coal and rock has a quantitative relationship with the infrared radiation response information on the surface,but the infrared radiation response mechanism and the quantitative characterization of the damage evolution are still scientific issues to be studied.In this dissertation,the self-designed multi-parameter observation system for loading coal and rock damage evolution and the numerical simulation are used to study the infrared radiation response characteristics in the macro and micro damage evolution process of coal and rock.On this basis,the intrinsic relationship between the damage evolution and the infrared radiation response information of loading coal and rock is revealed,and the infrared radiation response mechanism during the damage evolution of loading coal and rock is clarified.Finally,the characterization parameters of infrared radiation are determined,the infrared radiation quantitative characterization method for the damage evolution of loading coal and rock is established,and the stress-strain constitutive model of the loading coal and rock with infrared radiation data interface is constructed.The innovative achievements of the dissertation are mainly reflected in:(1)Background thermal noise correction methodology for average infrared radiation temperature of loading coal and rock is established.A multi-parameter observation method for damage evolution of loading coal and rock with reference coal and rock is proposed.It is found that the infrared radiation noise of the loading coal and rock is related to the reference coal rock,and the positive linear correlation coefficient is 0.993.On this basis,background thermal noise correction methodology for average infrared radiation temperature of loading coal and rock is established.The infrared radiation noise of the reference coal and rock is used to denoise the AIRT loading coal and rock,and the AIRT signal-to-noise ratio of coal and rock is increased from 0.40 to 70.69,which solves the AIRT distortion problem of loading coal and rock during the observation process.(2)Spatial-temporal infrared radiation precursors and stress control effects of coal and rock failure are found.A new index that named “Variance of Successive Minus Infrared Image Temperature(VSMIT)” is proposed.The time nodes of the coal and rock failure precursors are determined,and the time-space precursors and distribution characteristics of the “upcoming damage” and “initial damage” of the loading coal and rock are obtained by combining the successive minus infrared image at the corresponding moments.It is found that the control effect of stress on VSMIT has universal and significant characteristics.The stress-to-VSMIT control ratio was 89.8%,and the VSMIT mutation coefficient averaged 2 orders of magnitude of the stress mutation coefficient.(3)The infrared radiation quantitative characterization method for the damage evolution of loading coal and rock is established.The characteristics of synchronous mutation of VSMIT and acoustic emission damage variables are found,the intrinsic relationship between VSMIT and damage evolution is revealed,and damage accelerated infrared radiation marker points of loading coal and rock are determined.A new index that named “infrared radiation counting” is proposed.Based on the idea of “effective loading area to characterize damage variable”,the infrared radiation quantitative characterization method for the damage evolution of loading coal and rock is established,and the stress-strain constitutive model of the loading coal and rock with infrared radiation data interface is constructed,which can reflect the internal damage evolution of loading coal and rock by the infrared radiation response information on its surface.There are 84 figures,18 tables and 177 references in this dissertation.