Modeling of Time-Dependent Deformation of Jointed Rock Mass

To improve the understanding of time-dependent responses of jointed rock mass, a new creep model is developed and implemented in UDEC to simulate creep deformations of jointed rock mass considering time-dependent deformations of both rock and joints. First, the implementation of the Time-to-Failure (TtoF) model for rock and the creep slipping model for joint is introduced. Then, creep simulations are conducted to study the influence of joint dip and confining stress on the long-term stability of rock masses using square models with a single joint. Time-dependent deformation of a moderately jointed rock mass is simulated using a pillar model with multiple joints. Finally, a case study of a high rock slope in western Norway is conducted and the creep deformation mechanisms of the rock mass are analyzed by comparing two slope models with different joint strength properties. It is found that there is no unstable movement on the potential sliding surfaces of the slope. The proposed creep model of jointed rock mass provides a novel approach to analyze structural failures of jointed rock mass under creep loading conditions. Highlights A new creep model for modeling time-dependent deformation behavior of jointed rock mass is proposed. Time-dependent deformation of jointed rock mass is largely influenced by confinement and the angles between joint sets as well as the direction of the maximum principal stress. The axial strain rate and the lifetime of moderately jointed pillars are governed largely by the applied stress. There are no significant sliding deformations on the potential sliding surfaces of the Oppstadhornet rock slope from 2003 to 2011.