Igneous rock

Geochemistry

Metamorphic rock

Geotechnical engineering

Materials science

Mineralogy

Gneiss

Geology

Porosity

Strain (injury)

Rock mechanics

Petrology

Lateral strain

Internal medicine

Composite material

Compression (physics)

Medicine

Brittleness

Sedimentary rock

Rock Mechanics and Rock Engineering

In this paper, we have investigated the quantitative relationship between the axial strain threshold at the volumetric strain reversal point (ε 1cd) and the strain threshold at the peak stress (ε 1ucs) during the uniaxial compression tests. We found that normalized values of ε 1ucs/ε 1cd for different rock types are typically ~1.34(±0.24). This is especially true for igneous and metamorphic rocks, or low-porosity sedimentary rocks. To verify this finding, we investigated seven granitic gneiss samples using the uniaxial compression test. Our results were consistent with the above statistics. We inferred that ε 1ucs/ε 1cd may be an intrinsic property of low-porosity rocks, and may be a potential indicator for predicting failure strains in laboratory-scale rock samples.

A Potential Strain Indicator for Brittle Failure Prediction of Low-porosity Rock: Part I—Experimental Studies Based on the Uniaxial Compression Test