Research And Application Of The Design Method Of Rock Burst Parameters For Roof Deep Hole Pre-splitting Blasting

In this thesis,the author used theoretical analysis to study the factors of force source under the condition of thick hard roof and the pressure-relieving mechanism of pre-splitting blasting.The influence of force source on stress distribution under thick and hard roof was studied numerically.The influence of rock strata with different bursting liability on wave propagation is studied through laboratory experiments.The design method of pre-splitting blasting parameters was verified by field test.Based on the mechanism of preventing rock burst by stress control theory,the causes of surrounding rock stress under the condition of thick and hard roof are studied,and the influence of different factors on stress distribution is studied by numerical simulation.Based on the stress distribution law of surrounding rock,the mechanism of preventing rock burst caused by thick hard roof by pre-splitting blasting is studied,and the influence of coal and rock mass of roof with different bursting liability on wave propagation is analyzed,and the conclusion that stress only affects wave velocity within a certain range is drawn.Based on the study of blasting mechanism,the influence of different parameters on the pressure relief effect is analyzed,and three groups of parameters which have great influence on pre-splitting blasting are the amount of explosive,the diameter of blasting hole and the spacing of blasting hole.By means of theoretical calculation and numerical simulation,the design method of roof pre-splitting blasting parameters was obtained,the construction flow chart of thick hard roof with different bursting liability was designed,and the design scheme of parameter optimization and the construction parameter value of specific parameters were proposed according to the actual construction site.The obtained parameter design method was applied to the anti-blasting practice of 311307 working face in Bayan Gaole Coal Mine.By comparing the pressure-relief effect of the previous parameter design method,the rationality of the method to determine the parameters of pre-splitting blasting proposed by the author was verified.