Estimation of Long-Term Strength of Rock Based on Subcritical Crack Growth

Abstract

In this study, based on information about subcritical crack growth, the long-term strength of rock was estimated with consideration of changes in environmental conditions. The long-term strength of granite is known to be lower in water than in air. From the estimation of the long-term strength for the situation where the surrounding environment changes from air to water, it was revealed that when the environmental condition was changed from air to water, the long-term strength converged to that of rock continuously in water, even when a dry condition (where rock was kept in air) had been maintained for a long time (1 or 100 years). The results of long-term strength estimation indicate that the acceleration of crack growth in water strongly influences the estimated long-term strength of granite. It is therefore concluded that water has a significant influence on the long-term stability of rock mass structures such as rock slopes.