Interpretation of Rock Mechanics Data. Volume 1 - a Two-dimensional Finite Element Approach to the Evaluation of Underground Coal Mine Stability.
For Reference Only At Bureau Libraries :172 pages
A two-dimensional finite element program was modified and extended to account for some of the rock mechanics complexities associated with single-entry development of longwall coal mine panels. The program includes arbitrary assignment of element properties without regard to element ordering, anisotropic elastic, plastic and brittle rock properties that may be time-dependent (aging), arbitrary mining sequences, and provisions for the effects of artificial support on the adjacent strata. Failure is according to an extended von mises criterion that may be linear or quadratic in form; flow rules are obtained from the yield function taken as the plastic potential, but brittle behavior is treated as a discontinuous process of material properties change with deformation. The extent of failure is calculated from the external boundary conditions. Application of the program to essentially two-dimensional problems resulted in close agreement between calculated displacements and field measurements in the double-entry system. Bleeder entries were stable in one locality and not in another. Artificial support had little influence on stability.
CP; Final Contract Report;
For Reference Only At Bureau Libraries
University of Utah