Determination of the parameters of rock viscoelastic creep model and analysis of parameter degradation

Creep parameter determination

In practical engineering, the physical and mechanical parameters of rock under complex geological conditions obviously changes with stress and time. Parameters, such as the modulus of elasticity, strength, and viscosity, decrease over time. Therefore, the creep parameter is expressed as a functional expression of stress versus time better reflects the essential properties of rock materials. Under constant stress, the creep parameters are considered to be time-dependent. The shear modulus G₁ is constant and not affected by time under constant stress. The bulk…