The fractures of rock significantly affect the efficiency and safety of rock breaking caused by tunnel boring machine (TBM) disc cutters. The present study established a discrete element model of randomly fractured rock using the Monte Carlo method

and investigated the correlation between random fractures geometry parameters (dip angle

fracture diameters and fracture density) and rock mechanical properties (strength and elastic modulus) through uniaxial compression simulation. Subsequently

the randomly fractured rock breaking by disc cutter was simulated using the discrete element method (DEM). The results demonstrated a clear linear correlation between the dip angle

diameter and density of random fractures with the strength and elastic modulus of rock

and a multiple linear regression prediction model for the mechanical properties of randomly fractured rocks was established. During construction simulation

the rock-breaking specific energy increased with an increase in fracture dip angle

while it initially decreases and then increases with increasing fracture diameter and density. Based on numerical simulation results

a correction factor for rock-breaking force was introduced into the Northeastern University rock-breaking force prediction model

thereby establishing a prediction formula that accounts for the influence of random fractures.