Abstract
Background: Subcritical crack growth is one of the main time-dependent behaviors in rocks. Double torsion testing has been adopted to determine subcritical crack propagation parameters for granite specimens during water interaction, the crack growth time dependence of granite is also discussed on the basis of fracture mechanics.
Objective: The purpose of this article is to study the time dependent failure characteristic of granite during water rock interaction.
Methods: According to the corrosion theory, the linearity regression analysis was carried out on the experimental data, the relations between the subcritical crack growth velocity V and the intensity factor K were obtained both in natural state and in saturated water. Meanwhile, according to rock fracture mechanics theory, the relations between crack relative length l/b and crack growth time t were studied based on the subcritical crack growth parameters.
Results: The fracture toughness K decreases from 1.532 to 1.043 due to water effect. Meanwhile, the limit time of the specimen in saturated water is much less than that in natural state.
Conclusion: The water rock interaction has speed up the subcritical crack growth. This research provides a basis for the time-dependent stability in rock engineering.
Keywords: Water rock interaction, time dependence, subcritical crack growth, stress intensity factor, crack growth time, fracture toughness, crack relative length.
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