Journal of Geophysical Research Atmospheres · 1984 · 192 citations · 32 references
Natural SciencesGeologyMaterials ScienceCeramicsMechanical Behavior Of MaterialsRock MechanicsFracture InitiationFracture MechanicsFracture PropagationFracture ToughnessRock FailureRock FractureCrack GrowthFracture GrowthFracture Mechanics ExperimentsFracture Of CeramicsFracture Propagation AnalysisMicrocrack DevelopmentMicrocrack GrowthSubcritical Crack Growth
Stable crack growth strongly influences both the fracture strength of brittle rocks and precursory phenomena to catastrophic failure. The study aims to quantify how time and environment affect subcritical fracture propagation in rocks, addressing challenges of applying synthetic‑material techniques and incorporating microstructure, microcrack zones, and environmental roles. The authors use fracture mechanics experiments on five rock types, optical and SEM imaging, ceramic microstructure studies, and water‑induced time‑dependent tests to investigate subcritical crack growth.
Stable crack growth strongly influences both the fracture strength of brittle rocks and some of the phenomena precursory to catastrophic failure. Quantification of the time and environment dependence of fracture propagation is attempted with the use of a fracture mechanics technique. We examine some of the difficulties encountered when applying techniques originally developed for simple synthetic materials to complex materials like rocks. A picture of subcritical fracture propagation is developed that embraces the essential ingredients of the microstructure, a microcrack process zone, and the different roles that the environment plays. To do this we examine the results of (1) fracture mechanics experiments on five rock types, (2) optical and scanning electron microscopy, (3) studies of microstructural aspects of fracture in ceramics, and (4) exploratory tests examining the time‐dependent response of rock to the application of water.
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