Rock Mass Rating RMR Calculator
Bieniawski RMR total from the five sub-ratings (strength max 15, RQD max 20, spacing max 20, groundwater max 15, joint condition max 30) with the standard RMR class boundaries.
Description
Bieniawski RMR total from the five sub-ratings (strength max 15, RQD max 20, spacing max 20, groundwater max 15, joint condition max 30) with the standard RMR class boundaries.
Rock Mass Rating RMR Calculator: Bieniawski RMR total from the five sub-ratings (strength max 15, RQD max 20, spacing max 20, groundwater max 15, joint condition max 30) with the standard RMR class boundaries.
When to use Rock Mass Rating RMR
Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.
- R1 strength
- Sub-rating for intact rock strength (0-15).
- R2 RQD
- Sub-rating for RQD (0-20).
- R3 spacing
- Sub-rating for joint spacing (0-20).
- R4 water
- Sub-rating for groundwater conditions (0-15).
- R5 joints
- Sub-rating for joint condition (0-30).
How Rock Mass Rating RMR works
Bieniawski RMR total from the five sub-ratings (strength max 15, RQD max 20, spacing max 20, groundwater max 15, joint condition max 30) with the standard RMR class boundaries. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.1
- RMR
- Total RMR rating between 0 and 100.
- Class
- Rock mass class name and roman numeral.
Limitations and assumptions
- Geotechnical correlations and idealized failure models depend on stratigraphy, sampling disturbance, drainage, stress history, groundwater, density, anisotropy, scale, construction sequence, and laboratory or field method. Site-specific design requires investigation and code factors.
- Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.
Alternative or Complementary approaches
Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.
References
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Geotechnical engineering — Wikipedia contributors
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