Study On Risk Forecast Of Deep Buried Tunnel Rock Burst Based On Catastrophe Theory

In recent years,with the gradual development of underground engineering to the direction of "long,large,deep and group",the dynamic disasters such as rock burst occurred.Rock burst has become a world geological hazard at present.Because of the strong destructive and serious damage of rock burst,the safety,progress and cost of underground engineering are seriously threatened.In order to effectively prevent the occurrence of dynamic disasters such as high strength rock burst,it is necessary to study the rock burst in depth according to the characteristics of different engineering.It is of great significance for the design and construction of underground engineering to put forward the reliable and applicable detection and prediction methods and control countermeasures.The occurrence of rock burst is uncertain,stochastic and sudden,so the traditional theory can not be applied to the stability mechanism of surrounding rock well.Catastrophe theory focuses on the phenomenon and law of mutagenesis caused by continuous change.Therefore,it is a powerful tool to analyze the risk of rock burst.Firstly,on the basis of analyzing the disturbance and damage of surrounding rock caused by excavation,the formation mechanism and prediction method of rock burst are studied in this paper.Based on the application and research of the existing catastrophe theory,the catastrophe theory is briefly introduced.Secondly,the criterion of energy mutations criterion,the displacement model mutation criterion,entropy mutation criterion are applied to determine the stability of the surrounding rock system,and the accuracy of the criterion is verified by numerical simulation analysis.Thirdly,the rock burst proneness of rock mass was identified by field sampling and routine laboratory tests.And based on the principle of potential energy and the viewpoint of energy conversion.Then fold catastrophe model of deep high stress rock burst dangerous excavation system is established through the equilibrium relation of work and energy,and the criteria for predicting rock burst occurrence are derived.Finally,according to a coal mine project,the coal mine catastrophe model to evaluate the risk of rock burst are established based on fold catastrophe model.Through the evaluation of the catastrophic model,it is concluded that the rock burst will occur in the coal mine.Through the comparison with the actual data of the coal mine,the accuracy of the evaluation of the catastrophe model is obtained.And the applicability and feasibility of catastrophe theory in the prediction of rock burst risk are verified.