The Mechanics Analysis On Several Kind Of Rock-burst Geomechanical Models

Rock-burst is one of the main geologic hazards that restricted the tunnelconstruction. The domestic and overseas scholar studied the problem using variedmethod from the different views. At the present time, a unitized understanding has notbeen formed about the mechanism of the rock outburst. With the more and moreunderstructure work the damage caused by the rock outburst increased. The problemis one of the important puzzles of the understructure geologic hazards. The study onmechanism of the rock outburst is the base of the burst intensity degree and theoutburst forecasting, prevention and cure of the outburst, so it’s unguent andimportant to study the mechanism of the rock outburst. Among them, the mechanismof description and analysis of the mechanics of rock-burst is the important foundationof rock-burst prediction and prevention.After the excavation of tunnel surrounding rock mechanics effect of performanceis non-linear, and dynamic evolution of irreversible. Non-linear is the essentialcharacteristics of rock mass mechanics behavior. Therefore, to describe themechanical behavior of surrounding rock, prediction and control, can by thecontemporary theory of nonlinear science, establish suitable for rock mechanics andengineering characteristics of rock mass nonlinear system theory. Catastrophe theoryis one of the important means of nonlinear scientific research, its greatest advantagerelative to other nonlinear scientific theory is that catastrophe theory based on severalassumptions, even don’t know the system of differential equation and differentialequation of conditions, can also be some of the system is deduced by several variablesquantitative or qualitative.Li Tianbin professor is presented in this paper summarized the six kinds ofrock-burst of geological mechanics model, based on the basis of the three kinds ofgeological mechanics of rock-burst mode, through the high in-situ stress brittle rockmass mechanics methods to analyze three kinds of geological model into rock massmechanics model, through the mutation theory, the cusp catastrophic model of rockmass mechanics model can be converted to, namely mathematical model, to establisha mathematical formula, and then by a mathematical formula to deduce the rock-burst criterion, etc. Results are listed below:(1) With knowledge of fracture mechanics to analysis of surrounding rock massof surrounding rock mass splitting into plate mechanism, criterion and splitting intoplate is deduced. According to the forming mechanism of splitting into boards, thequalitative analysis of tensile fracture-flake type rock-burst criterion.(2) We carried out analysis of the bend-drum fold geomechanics models andbuild a reasonable mechanics model. Using catastrophe theory, we convert mechanicsmodel into the cusp catastrophe theory model. By analyzing the cusp catastrophetheory model, we deduce the criterion of instability of surrounding rock or rockoutburst, with Jinping hydropower station as an example, the rationality of thevalidation criterion formula.(3) We carried out in-depth analysis of the transverse bend-drum foldgeomechanics models and build a reasonable mechanics model. Using catastrophetheory, we convert mechanics model into the cusp catastrophe theory model. Byanalyzing the cusp catastrophe theory model, we deduce the criterion of instability ofsurrounding rock or rock outburst, with Jinping hydropower station as an example,therationality of the validation criterion formula.(4) We carried out in-depth analysis of tensile fracture-slip geomechanics modelsand build a reasonable mechanics model. Using catastrophe theory, we convertmechanics model into the cusp catastrophe theory model. By analyzing the cuspcatastrophe theory model, we deduce the criterion of instability of surrounding rock orrock-burst, with Jinping hydropower station as an example, the rationality of thevalidation criterion formula..