Analysis Of Elasto-brittle-plastic Rockmass Based On Damage Mechanics And Research Of Anchor Rod Support Model

Analyzing the stability condition for surrounding rock of underground engineering with elasto-plastic theory have offered us much accurate data for the design of the underground engineering. Beyond all doubt ,the significance of this theory to the developing of the technique of underground engineering is immeasurable.The rock mass is not a homogeneous material, actually it is a material with many crannies, eyelets and faults. When the load putting on the structure is increasing ,the crannies and eyelets in the rock mass will come into being and extend, which will decrease the capability of the rock mass's bearing load. And with these crannies ,eyelets extending ,they must become a faults though the rock mass at a time .And at this time if the load increases ,the structure would be destroyed. The measure dealing with this phenomena with classic elasto-plastic theory is generally reduce the value of the parameter of the material. But with the technique of underground engineering developing, the cavity with the large and super large section become more and more common, so the precision of classic theory dose not meet with the people.How to calculate the action which the crannies eyelets putting on the structure become a focus . The first time which the damage mechanics was applied in the analysis of the concrete structure appeared in 1976, which was found in the Dougill's literature. This theory become more and more feasible with the 30 years developing. However people have not had a common idea for the definition of variable of damage up-to-date. In this paper, the author give the definition of the variable of damage from the view of the strain and give the expressions of the variable damage in the state of the complex stress. And the conclusion is reasonable when this theory is applied the analysis of the underground engineering. At the same time the author give the measure of calculating the stress-falling when the structure being destroyed .How to get more profit and spend less resource become a interesting problem, especially when the economy of our state is increasing. When designing the anchor bolt supporting ,people often adopt the way of analogy. Without doubt, this way has provided us a much higher efficiency. However every engineering has its own characteristic, if we adopt this way in the designing ,we would spend more resource which will be wasted. So we must find a more accurate measure in which we can get the action data of the anchor bolt supporting and provide the schemes on the optimizing designing of the anchor bolt supporting. In this paper the author give the numerical model of the behavior of the anchor bolt and get a reasonable conclusion when applying this theory to the analysis of the stabilization of the underground engineering .In addition an efficiency way in which we can get the 3D-information of the anchor bolt model with AutoCAD and ANSYS has been proposed in this paper.