Rock Mass Rating Calculator
Uniaxial Compressive Strength (MPa)
Rating: 0-15
Please enter a valid number >= 0.
RQD (%)
Rating: 3-20
Please enter a valid number between 0 and 100.
Joint Spacing (mm)
Rating: 5-20
Please enter a valid number > 0.
Joint Condition
Select...
Very rough surfaces, no separation, hard joint wall
Rough, separation <1mm, hard joint wall
Slightly rough, separation <1mm, soft joint wall
Slickensided, or gouge <5mm, or separation 1-5mm, continuous
Soft gouge >5mm, or separation >5mm, continuous
Rating: 0-30
Please select a joint condition.
Groundwater Condition
Select...
Completely dry
Damp
Wet
Dripping
Flowing
Rating: 0-15
Please select a groundwater condition.
Calculate RMR
RMR Value:
Class:
Rating Breakdown
UCS Rating:
RQD Rating:
Joint Spacing Rating:
Joint Condition Rating:
Groundwater Rating: