Estimations with RMi

Published on February 15 2015

A. Estimate of rockmass properties

1. Estimates of rockmass strength. As shown in papers on RMi, the RMi-value approximately gives the uniaxial compressive strength of a rockmass. The RMi-value can be found from:

2. Estimate of deformation modulus as described in the paper The deformation modulus – comparisons between in situ tests and indirect estimates.

3. Estimate of input parameters to Hoek-Brown failure criterion for rockmasses as described in the Ph.D. thesis on RMi.

For measurements of jointing features, see the tag ‘Joints and jointing and the paper on seismic velocities.

Rock support is also described in the introduction paper to RMi. The RMi support charts are presented here.

B. Estimate of rock support

The RMi is used in rock support as described in several papers, see the tagPapers on RMi, especially the paper Recent developments in rock support estimates by the RMi.

The estimate of rock support can be found by application of the computer spreadsheet on Rock support

Important quotations are presented below from time to time:

”…..there is still no acceptable substitute for the field mapping and core logging carried out by an experienced engineering geologist.”
Evert Hoek, 1986.