Numerical simulations of mechanical and hydraulic behaviors of rock joint considering the first and second order asperity degradations

摘要

In this study the concept of equivalent second order asperities was devised and incorporated to the elasto-plastic joint model. Two asperity angles and two damage coefficients were introduced to handle the degradation of two types of asperities. Based on this formulation monotonic and cyclic shear behaviors were numerically simulated and compared with the test results of rough rock joint specimens. Characteristic shear behaviors of rock joint could be well simulated by utilizing the degradation of first and second order asperities. Variations of joint permeability with the shear displacement were also investigated using the hydraulic model which could consider the gouge production and aperture change.