Abstract: In cold-region rock engineering, ice-filled fractures significantly weaken the mechanical properties of the rock mass, which severely impacts the safety and stability of the project. To investigate the mechanical behavior and failure mechanisms of ice-bearing fractured rock masses, uniaxial compression tests, acoustic emission monitoring, and discrete element numerical simulations were conducted. The study systematically examined the mechanical characteristics and failure mechanisms of ice-bearing fractured sandstone, focusing on how fracture thickness (5-30 mm) and dip angle (0°-90°) influenced rock mass strength, elastic modulus, energy evolution, and crack propagation. Results showed that compressive strength, elastic modulus, and pre- and post-peak energy all non-linearly decreased with increasing fracture thickness, with the elastic modulus dropping by 20%-34%. The fracture dip angle was found to dominate the classification of failure modes. Vertical fractures (90°) exhibited the highest strength (23.56 MPa) due to efficient stress transfer, while low-angle fractures (15°-30°) experienced a 30%-45% reduction in strength due to interface shear effects. Three failure modes were identified: ice layer crushing (α≤15°), interface slip (15°-75°), and rock main fracture (α≥75°). A micro-parameter system for the ice-rock composite medium was developed based on the PFC discrete element model, with simulation results showing over 90% agreement with experimental data. By considering the coupling effects of fracture thickness and dip angle, the D-P strength criterion was modified, and the theoretical values showed an experimental error within ±5%. These findings provide theoretical support for the stability evaluation and disaster prevention in cold-region rock engineering and lay the groundwork for studying ice-rock interaction mechanisms in complex freeze-thaw environments.