Research On Multi-source Information Fusion Warning Of Rock Burst In Hengda Coal Mine

China’s coal mining depth is extending to the deep year by year.With the increasing mining depth,the problem of high ground stress becomes prominent,the stope structure becomes more complex,and the risk of rock burst increases significantly,which seriously threatens the safety of coal mine production.The main coal seam of Hengda Coal Mine has weak bursting liability,and the top and bottom of the coal seam have strong bursting liability.Influenced by mining depth,high ground stress and fault,the risk of rock burst occurs in the mining process is large.The existing monitoring and warning methods can no longer meet the actual production needs.In this thesis,based on the actual engineering background of Hengda Coal mine,combined with the existing monitoring means of working face,the monitoring indicators are selected on the principle of scientificity,comprehensiveness and dynamics,and the fuzzy comprehensive evaluation method is adopted for fusion.Finally,the multi-parameter fusion warning model of rock burst applicable to Hengda Coal mine and mines with similar geological and monitoring conditions is established and applied to engineering practice.The main research results are as follows:（1）In the mine field of Hengda Coal Mine,faults crisscrossed,cracks developed near faults,fractured coal beds,and the main coal seam is deep mining.According to the occurrence conditions of the main coal seam of Hengda Coal mine,the main influencing factors of rock burst in the process of coal mining are analyzed,and the physical and mechanical parameters of the ground stress,coal seam and roof and floor of Hengda Coal mine are tested.It is concluded that the main coal seam of Hengda Coal mine has weak bursting liability,while the top and floor have strong bursting liability,and the risk of rock burst in the mining process is large.Moreover,there are multiple yield,critical and supporting coal pillars near the main roadway,which is easy to cause rock burst caused by dynamic instability of coal pillars.（2）Microseismic events are analyzed by G-R relation and signal analysis method in basic theory of seismology.Based on the energy level-frequency analysis of G-R relation,the energy classification standard is determined.Based on the time series analysis of microseismic energy and frequency,the response relationship between large energy events and rock burst is determined.In addition,it is found that large energy events and microseismic energy cloud maps have good coupling.The response relationship between microseismic b value and high energy events is also analyzed by G-R relation.Fourier transform,wavelet packet transform and other signal processing methods are used to analyze microseismic signals in time-frequency domain.It is found that compared with small events,large energy microseismic events have lower main frequency,high amplitude and higher energy distribution in low frequency band in frequency domain.Based on the analysis of the precursory characteristics of rockburst microseismic,the microseismic monitoring indexes such as microseismic energy,spatial characteristics,b value and spectral characteristics are determined.（3）Through the analysis of the variation trend of acoustic emission and electromagnetic radiation during the occurrence of typical large energy events,it is found that the trend of acoustoelectric fluctuation before the occurrence of large energy events has"upward","inverted V","N"and so on.According to wave theory to quantify the acoustoelectric volatility analysis,determine the acoustic emission intensity fluctuation gradient|?|and electromagnetic radiation intensity fluctuation gradient|?|as acoustoelectric sensitive response index,etc.According to the analysis of the deep hole stress and shallow hole stress of the main roadway in the working face,it is found that the internal stress of coal rock mass is concentrated and the sensitive response of rock burst is improved during the drilling stress increase.According to the stress response relationship,the stress change rate index?is introduced to describe the stress fluctuation quantitatively.（4）A multi-parameter monitoring index system was established based on the analysis of microseismic,acoustic-electric and stress precursor laws.Fuzzy comprehensive evaluation method was used to analyze the weight of each index and the sensitivity of each index to the impact risk.Firstly,each index was subdivided and quantified to obtain the critical value of the early warning index;Then,the analytic hierarchy process（AHP）is used to establish a discriminant matrix based on the judgment and comparison scale criterion,and the weight of each index is determined according to the sensitivity of the monitoring results of each monitoring method to rock burst and the actual situation on site.Finally,the membership function is used to classify each index,establish the membership function of each index,effectively integrate each index,and establish a multi-source information fusion warning model of rock burst in Hengda Coal Mine.Subsequently,the practicability of the model was successfully verified on site.The thesis contains 43 figures,16 tables and 107 references.