Engineering Aspects of Igneous and Metamorphic Rocks

The Plutonic igneous rocks are characterized by granular texture, massive structure and relatively homogeneous composition. In their unaltered state, they are essentially sound and durable with adequate strength for any engineering requirement (Table 5.28). In some 

1 Less than 1.8 Very low Over 30 Very high 

5 Over 2.75 Very high Less than 1 Very low 

Term Strength (MPa) Term Strength (MPa) Term Strength (MPa) 

Very weak less than 1.25 Weak Under 15 Very low Under 6 

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