A Study of the Nonlinear Creep Damage Model for Rocks
(1 College of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055;
2 College of Civil Engineering, Chongqing University, Chongqing 400045)
Abstract��
To illustrate the entire process of rock creep, this paper presents an improved elastic component based on damage mechanics theory and Kachanov's creep damage law, which considers time-dependent damage and reflects the instantaneous deformation that occurs under loading and accelerated rock creep. Additionally, it sets forth a new two-component nonlinear creep damage model and deduces the creep equation by connecting the elastic component with a fractional order viscous component describing the attenuation and steady creep of rock in series. By comparing the creep test results with related literature, analysis shows that the proposed model can accurately reflect the three stages of the rock creep process and the fitting curve agrees well with the test curve, proving the rationality and applicability of the improved model.
2014, Vol. 51 