PFC-FDEM multi-scale cross-platform numerical simulation of thermal crack network evolution and SHTB dynamic mechanical response of rocks

• Developed a novel multi-scale cross-platform PFC-FDEM coupling methodology for simulating thermal-mechanical rock behavior. • Identified three-stage crack evolution with temperature-dependent density following an exponential model. • High-temperature exposure reduces dynamic strength ratio by 60% at 800°C and diminishes strain-rate sensitivity. • Numerical predictions show excellent agreement with experiments (±8% peak stress-strain errors).