| "Rockburst" is one of the typical dynamic force calamity of coal mine with rather complicated cause.When it accoured,there will be included other serious mine disasters.such as "Coal and gas outbursts".Therefore,in order to investigate the risk assessment and prevention of the rock burst pressure in the deep mine,this paper establisted a evalution system on the facters of burst pressure in mine well,which is based on the "hierarchy process analysis" and "ambiguity evaluation" theories.and based on the "level analysis" and "fuzzy evaluation" theories,the risk of rock burst is established.And the program about danger evalution of burst pressure in mine well was also established using Java language,which can be used to analysis the risk of different section of mine well.then,At the same time,based upon the mechanical theory of rock burst to mine roadway,the process of occurrence for Rock burst in roadways was simulated using the Dynamics Software LS-DYNA creatively.The effects of source dimension,the thickness of the weak structure and the quality of roadway support on the roadway surrounding rock stability were discussed.The main research contents and conclusions of this article are as follows:(1)The influencing factors of roadway impact rock pressure are include three categories namely,impact tendency,geological condition,mining factors,which divided,into fifteen subcategories further.Which divided into fifteen subcategories.First of all,a detailed analysis on the factor of impact tendency has been carried out,which based on the theory of current impact tendency index and damage statistical constitutive model,as well as adopted the new impact assessment index--the change rate of surplus energy index.Based on this,the test of impact tendency index was carried,out.At the same time,factors such as deep mining factors and hard roof thickness were also be analyzed.At the same time,the factors such as deep mining factors and hard roof thickness were analyzed.The results show that at the depth of 540m in HuJiaHe mine well,where have a higher tendency of coal strike and a thicker sandstone roof,have basic conditions for the occurrence of rock burst.(2)Based on the "hierarchy process analysis" and "ambiguity evaluation" theories,the evaluation methodology for the compressive consideration of the riak for burst rock were created.The evaluation system which can be browsed through the display serve was established with JAVA language,and risk assessment of rock burst in five sections of underground coal mine were made as follow.The results show that the evaluation results obtained by this software program are basically consistent with the on-site monitoring results.Therefore,this evaluation system established in this paper can be used for the risk rank in mine well quickly and accurately.(3)The prevention mechanism of rock burst in roadway was analyzed according to the control theory of surrounding rock structure in roadway with impact rock burst and a simplified "strong-weak-strong" roadway surrounding rock mechanical model is established as well as the analysis of its strength,energy absorption,vibration reduction and other characteristics.Conduct detailed analysis.At the same time,the roadway anti-impact strategy is proposed to be "affordable,protected and fast."(4)At the same time,based upon the mechanical theory of rock burst to mine roadway,the process of occurrence for Rock burst in roadways was simulated using the Dynamics Software LS-DYNA creatively.The results show that the above three factors have obvious influence on the stability of roadway surrounding rock,but there is a reasonable range for both the weak structure thickness and the support quality.Therefore,it's the key factor to set a reasonable parameters to effectively control the rock burst in engineering practice. |
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