A Hybrid Numerical Modeling for Cross‐Scale Mechanical Properties of Rock Materials

ABSTRACT To investigate the mechanical properties of fractured rock masses, a novel numerical model is proposed to characterize jointed rock masses via breakable Voronoi blocks and discrete fracture networks (DFNs). Based on the block scale factor and the strength factor, a meso‐parameter calibration method is established to correlate the parameters of intact rock blocks and jointed rock masses. The proposed model can effectively simulate the strength and fracture mechanisms of intact to moderately jointed rock masses. The joint dip angle, density, and length significantly influence the fracture mechanisms and strength of rock masses. The excavation damage zones of tunnels are controlled by joint dip angle, with long fractures dominating macroscopic instability. The acoustic emission (AE) characteristics can quantify the damage degree of the surrounding rock and are closely related to joint density, as well as the stress coupling between joints and excavation boundaries. This study provides an efficient analytical method and theoretical basis for the mechanical analysis of jointed rock masses and engineering stability assessment.