A state‐of‐the‐art review on creep damage mechanics of rocks

Abstract

In many major rock projects, services have spanned decades or even hundreds of years. For engineering design, it is necessary not only to ensure the safety of personnel during construction but also to ensure the safety of long‐term use and operation in the future. Therefore, it is indispensable to study the creep damage mechanical properties of rocks before the construction of the project. For a long time, rock creep has been an important reason for large deformation and even instability in building foundations, underground tunnels, and slopes. Moreover, the surrounding rock generally exhibits obvious creep damage characteristics under an environment of high stress, high temperature, and high water‐pressure. Under certain geological conditions, this creep damage behavior is extremely prominent. Therefore, the study of rock creep damage mechanics is very important. This paper reviews the advancement of rock creep damage mechanics from the aspects of mechanisms, research methods, constitutive models, and so forth. Rock creep is a process of interaction between structural damage and the hardening effect. The structural damage and hardening effect are opposite to each other, but they exist in the same physical process. The creep research method introduces mainly the research objects, influencing factors, monitoring methods, and experimental methods. Creep constitutive models introduce mainly empirical models, linear element combination models, nonlinear combination models, and other nonlinear models based on new theory. Finally, based on the current research progress, several important research directions in rock creep damage mechanics are pointed out.

A semiempirical constitutive relationship for rocks under uniaxial compression considering the initial damage recovery

“…For this method, the damage variable is deduced within an irreversible thermodynamic framework based on experimental data. The damage variable and corresponding constitutive model can be obtained using different parameters such as P‐wave velocity, 33 apparent equivalent strain, 34 acoustic emission signals, 35 elastic modulus, 36 ultrasonic elastic wave velocities, 37 porosity, 38 crack density, 39 second order crack density tensor, 40 permeability coefficient, 41 residual strain, 42 special moment tensor, 43 energy density, 44 and energy dissipation 45 . Lately, Liu et al 46 proposed a dual‐damage constitutive model based on the uniaxial compression test results of rocks at different temperatures.…”

Fracture evolution and fracture mechanism of tunnel surrounding rock: A case study based on laboratory tests and theoretical analysis

“…31,32 During this process, the energy stored in the materials will be released in the form of elastic waves, which is referred to as AE. [33][34][35] Based on AE monitoring technology, this work obtained AE parameters in the failure process of the straight-walled arched tunnel simulation samples and focused on the analysis of the evolution of the AE ring count, as shown in Figure 8.…”

High-Temperature Creep Behavior of a Nickel-Based Single-Crystal Superalloy with Small-Angle Deviation from [111] Orientation

“…When the stress concentration value was greater than the yield strength of the c′ phase, the dislocation could be sheared into the c′ phase. Since the c′ phase was an important strengthening phase in the alloy, the dislocation of cutting could reduce the strength of the c′ phase and reduce the creep resistance of the alloy until creep rupture [25]. Terefore, the strength of the c′ phase was closely related to the creep resistance of the alloy [26].…”