Theoretical characterization of the temperature‐dependent mode I fracture toughness of rocks

Abstract

Mode I fracture toughness, as a key index to reflect rocks' resistance to crack propagation and failure, which is significantly affected by temperature, plays an important role in accident prevention in underground engineering. In this work, a temperature‐damage‐dependent fracture surface energy model of rocks was developed first. Then, the theoretical characterization model of the temperature‐dependent mode I fracture toughness of rocks was proposed according to the relationship between the fracture surface energy and fracture toughness. All obtained experimental results are used for verification, and the predicted values are in good agreement with the experimental results. The temperature‐dependent mode I fracture toughness model of rocks established in this study not only provides a new method to predict the fracture toughness of rocks at different temperatures conveniently but also provides the theoretical basis to the research on stability analysis, monitoring, warning, and disaster control of underground rock engineering.