| Fracture spacing , such as joint , mining area rupturing , ocean rupturing , earthquake network ,etc. are the rhythm phenomenon of geology distributed and existed extensively, and the structure of the whole space network is unanimous from joint to the earth's crust rupture, among them, this must include the profound meaning that not discovered so far, and may be controlled by the same mechanism or the mechanism with the essential connection., So it is very important to study the regularity of uniformpiston of structural face. It is not only a foundation that we abstract the information of geology as the model of geology and mechanics but also is basis that theory of rock mechanics had been founded and perfected. We understand the condition and the influence factor or mechanism, which fractures spacing had been occurred, and also can forecast the distribution of ore body as well as the phenomenon of earthquake. In this study, some research had been carried out in this respect. Firstly, by the experiment with the influence of loading rate to rock breaking state under the condition of plane stress, we had observed that the change of loading rate could bring the transform of jacking rupture to shear rupture. The occur of earthquake is usually thought as the process of ore body's shear rupture, and the reason is the result in dynamic loading that the strain energy within the earth suddenly released. The crustal rock will occur the shear rupture and form the phenomenon of approximate and rhythm uniformpiston. Secondly, the simulation experiment of equivalent material had been carried out for the research of deformation rupture rule of top stratum with two-side equal stress in local area. Presented the mechanic reason that the terrane appeared bucking deformation and then entered shear-open rupture, finally formed uniformpiston of structural face with horizontal pressure. Using the bucking theory of the board and the relationship between bucking fold and rupture, we probed into the influence of different confining pressure to X shear joint spacing of rock and using the concept of bucking fold controlling rupture, the phenomenon of resemble simulation experiment to top stratum and formative mechanism of earthquake network were analysis deeply. We have roughly recognized that the pieces character of seismic activity, namely the character of equal interval activity was controlled by the earth's crust flections Finally, we presented that wave transfer of horizontal compressive stress (strain) is the mechanics reason that the terrane appeared bucking deformation and then entered shear-open rupture by using of plasticity theory of gradient from angle of localization of strain within macroscopical range, and the model of strain gradient theory is established in plane strain state. By the analysis of the plastically deforming area of rock using plasticity theory of gradient, we can conform that the distribution of the plastically deforming curved face have the law of fracture spacing , the networks distribution pattern and the argument are related to confining pressure, the scale of rock ,Young's modulus E ,falling modulus λ , internal parameter of the materiall and analyze how confining pressure affect plastically deforming ε p. The conclusion is identical in some document results, this prove that plasticity theory of gradient not only can approximately describe the fracture spacing phenomenon, but also we can unify large scale earthquake network and small conjugate shear network of rock. In this paper, the discussion for the phenomenon of rock fracture with different scale was carried out at home and abroad firstly, and the above conclusions acquired by the research of experiment and theory. This subject presents the challenge to the theory of rock mechanics, and has huge application values for the prediction of rupture, energy sources prediction controlled by rupture, the control of earthquake's occur and evolution and prevention of engineering disaster.
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