Simulation Analysis of Dynamic Properties of MOC-SLP After Freeze-Thaw Cycles

To reveal the dynamic mechanical properties of magnesium oxychloride cement-stone powder (MOC-SLP) after freeze-thaw cycles under high strain rates, a computational model of the split Hopkinson pressure bar was constructed using ANSYS/LS-DYNA.The dynamic impact process under different impact velocities was simulated, combined with the variable of 0-20 freeze-thaw cycles.The dynamic stress-strain response, energy absorption characteristics, and failure morphology evolution were analysed.The entire dynamic damage process of specimens was tracked also.Results show that MOC-SLP exhibits significant strain rate hardening effects.MOC-SLP still maintains strain rate sensitivity after freeze-thaw cycles, but the hardening amplitude decreases, reflecting the dynamic load-bearing potential of damaged specimens.As the number of freeze-thaw cycles increases, the failure mode of specimens transforms from axial tensile failure to shear-tensile composite failure, with aggravated brittle failure characteristics and more fragmented failure morphology.This study provides the theoretical support for their application in impact and explosion protection environments.