For the case of plane strain and with Coulomb -- Mohr's criterion for rocks, the authors constructed the post-limit deformation equations that coincide in form with the plastic flow theory. It is ...shown that the system of differential equations is hyperbolic. The authors also obtained four characteristics that are nonorthogonal by symmetric relative to the first principal direction, and determined relations on the characteristics. It is found that solution of problems on failure requires that both the stress vector and displacement vectors are assigned at the contour where failure begins.
Based on the analysis of the post-limit deformation stage, it is shown that under soft loading of rocks, displacement rate greatly increases in the post-limit deformation zone, and the kinetic energy ...grows as well. It is supposed that given the kinetic energy reaches a certain threshold value, a rock block exposed to the post-limit deformation splits off the rock mass. This assumption is applied to studying the phenomenon of zonal disintegration of rocks surrounding deep cylindrical tunnels.
The method of
in situ
X-ray diffraction with the influence of temperature and pressure on the sample was successfully applied in Siberian Synchrotron and Terahertz Radiation Centre on the ...experimental station
Diffractometry in hard X-rays
. High-pressure water-containing lawsonite silicate CaAl
2
Si
2
O
7
(OH)
2
·H
2
O is obtained at 400°C and 25 kbar in a diamond anvil cell during the decomposition of laumontite.
In situ
diffractometry of the reaction products helps to determine parameters of the unit cell of lawsonite and phase composition of CaO-Al
2
O
3
-SiO
2
-H
2
O at 400°C and 25 kbar.
The study is carried out into the stability of edges of open pits with a stratified structure. The angle of the strata slope and the ultimate elastic compressive and shear strengths are assigned. The ...maximal allowable depth of an open pit is determined depending upon the pit edge incline. The problem is solved from the constructed equations of plasticity of a stratified material. The limiting loads under which the plastic zone come onto the pit side surfaces and cause the pit slope stability loss are calculated.
Erratum to: Publisher’s Erratum Adushkin, V. V.; Kishkina, S. B.; Kulikov, V. I. ...
Journal of mining science,
2017/9, Letnik:
53, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Due to a technical error volume 53, issue 4, 2017 has been published online with an incorrect cover data. The issue has erroneously been distributed with the cover date July 2018. The correct caver ...date for volume 53, issue 4 should be July 2017.
The mathematical and mechanical models of elastic and elastoplastic deformation of block rock mass are developed. The problems of rigid punch indentation into a rock mass and the stress-strain state ...around a cylindrical working are considered.
The mathematical model is constructed for the elastic and elastoplastic deformation of stratified rock mass. The examples are presented for solving the plastic problems on mine working in block ...massif and indentation of hard die block under various conditions of plasticity.
This paper describes energy distribution in a block medium simulated by a one-dimensional chain of masses joined by springs and dampers. Equations describing the motion of masses are solved by the ...methods of the theory of ordinary differential equations. The effect of the block medium parameters on energy dissipation is investigated. An approximate analytical solution is obtained that describes the total energy of a block medium at large values of time.
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