Research On Regional Stress Field CT Detection And Multi Parameter Integrated Early Warning Technology In Outburst Coal Seam

Coal and gas outburst is one of the main disasters in the process of coal mining in China.Reliable monitoring and early warning is the key to prevent and control coal and gas outburst.Dynamic stress,static stress and gas pressure are the power sources of coal and gas outburst,which should be paid attention to in the process of monitoring and early warning of coal and gas outburst.Based on this,this paper experimentally studied the multi parameter response characteristics of P-wave velocity,electromagnetic radiation(EMR),acoustic emission(AE)and so on in the process of outburst coal rock loading and fracture,puts forward the regional microseism(MS)and seismic wave CT detection technology method suitable for outburst dangerous coal seam,constructs the multi parameter integrated early warning model of AE,EMR and gas in the local key area of outburst dangerous coal seam,and finally forms the CT detection and multi parameter integrated early warning technology of stress field in outburst dangerous coal seam area,and carries out the field application verification.In this paper,the response characteristics of P-wave velocity in the process of loading and fracture of gas bearing outburst coal are studied experimentally,and the technology of regional MS and seismic wave CT detection suitable for outburst dangerous coal seam is established,and the field measurement is carried out.The results show that the influence of gas pressure on P-wave velocity is relatively small,and the influence of gas pressure on P-wave velocity accounts for about 10%of the influence of stress on P-wave velocity.There is a formal power function relationship between stress and P-wave velocity during the loading process of outburst coal and rock samples.Based on this,a coupling relationship model between stress and P-wave velocity is constructed.Based on the coupling model,the distribution characteristics of regional stress field are consistent with the theory,and the reliability and accuracy of regional stress field CT detection results are verified by portable EMR contrast.It is found that the spatial location of the outburst danger area and the stress concentration area are consistent,which provides an example for the feasibility of detecting the outburst danger area by using MS and seismic wave CT technology.The precursory response law of EMR,AE and other parameters before outburst coal and rock fracture is studied by experiment.The integrated multi parameter early warning method of EMR,AE and gas in the local key area of outburst danger is established,and the field measurement is carried out.The results show that EMR and AE have a positive correlation with the loading stress of coal and rock samples,and the signals of EMR and AE have a good consistency in time,the intensity is not strictly positive correlation,and there is a certain difference.The deviation value processing method of acoustic and electric signal is put forward,and the deviation value index,deviation abnormal duration,abnormal frequency and other indexes have obvious response to the outburst danger precursor.The multi parameter integrated detection and early warning index system of outburst dangerous coal seam is studied and established,and the dynamic monitoring and regional detection model of outburst dangerous micro earthquake and the multi parameter integrated early warning model of local AE,EMR and gas are constructed.The application results show that the new method of MS and seismic wave CT detection in outburst coal seam area can effectively detect the key outburst danger area;the integrated multi parameter early warning technology such as EMR,AE and gas can timely early warning the outburst danger event,solve the problem of inconsistent single parameter early warning results,improve the early warning reliability of outburst danger and the pertinence of disaster prevention and control.The research results realize the regional local integrated detection and early warning of outburst danger,provide a systematic detection and early warning new method for outburst danger coal seam monitoring and early warning,and provide technical guarantee for the safe mining of outburst danger coal seam.The paper contains 105 figures,21 tables and 202references.