Numerical Simulation on Shear Behavior of Double Rough Parallel Joints Under Constant Normal Stiffness Boundary Condition

The shear characteristics of rock joints under constant normal stiffness (CNS) boundary condition are critical to the stability underground engineering mass. Five different joint profiles with random morphology were constructed using independent segmentation method Hurst exponent. Based on continuously yielding model, discrete element calculation models double rough parallel surface roughness and spacing CNS established UDEC software investigate effect condition. results show that condition, stress, displacement, resistance index (SRI) all increase coefficient (JRC) for both single- double-joint specimens, these single-joint greater than double-joint. With d , peak stress τ y (SRI p ) a gradually increasing trend, influence SRI is JRC, linear trend JRC. same displacement also, increased amplitudes increase; JRC two parameters also an trend.