| Abstract: | Conclusions The deformation of the blocky mass around a working can be interpreted as displacement of the material in a convergent radial
channel with an aperture angle of 360°. A kinematic scheme permitting the formulation of the problem in statically determined
form (similar to the classical scheme for calculation of the pressure of the earth at a supporting wall) is constructed.
Axisymmetric solutions for different levels of block interaction on contact are given. Estimates of the carrying capacity
are obtained in the case of rigid-plastic contact between the block and in conditions of dry friction. It is shown that this
scheme admits of transition in the limit to the accurate solution of the Lame problem in the continuum formulation.
Cases in which increase in the relative slip between the blocks leads to decrease in the interaction force between them (weakening)
are considered. With slight weakening, the deformation is a stable process. If the weakening is greater than a critical level,
the solution becomes unstable, which indicates the uncontrollable release of stored elastic energy from the mass.
Institute of Mining, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy
Razrabotki Poleznykh Iskopaemykh, No. 6, pp. 7–15, November–December, 1990. |
