Rock strength parameters from classification and testing - Geotechnical Investigation and Design Tables - page 73

Table 6.11 Variation of rock strength (Berkman, 2001).
Uniaxial compressive Strength Rock classification

strength (MPa)

Sedimentary Metamorphic Igneous

15 Lowest Welded Tuff

20 Sandstone Porphyry

25

⏐

Shale Granadiorite

30 Sandstone

45 Limestone Schist

60 Dolomite Granadiorite

70 Quartzite Granite

80 Rhyolite

90 Limestone Granite

100 Dolomite, Schist

Siltstone.
Sandstone

150 Granite

200 Quartzite

220 Highest Diorite

Figure 6.2 Rock type properties.

6.13 Relative strength - combined considerations
•

The above acknowledges that the description of rock strength from various sources
does vary.

•

Combining the rock strengths from various sources is included in this table.