Abstract: Using a split Hopkinson pressure bar (SHPB) system, impact loading tests were performed on frozen cement clay and frozen cement sandy soil to investigate their dynamic response characteristics under impact.The dynamic stress-strain curves, dynamic elastic modulus, dynamic peak strain and strength, and macroscopic failure modes of the two soil types were analyzed under varying freezing temperatures and impact pressures.Based on the energy conservation law, the optimal energy absorption efficiency of the soils was evaluated using energy flow transformation theory, thereby analyzing the dynamic damage process of frozen cement clay and cement sandy soil from a mechanistic perspective.The results indicate that the dynamic peak strain, strength, energy absorption efficiency, and degree of macroscopic damage in both frozen cement clay and cement sandy soil increase with rising impact pressure and decreasing freezing temperature.The peak strength of frozen cement clay is higher than that of frozen cement sandy soil, whereas its dynamic peak strain and energy absorption rate are lower.The dynamic elastic modulus of both soils initially increases and then decreases as the freezing temperature decreases.The optimal energy absorption efficiencies of frozen cement clay and cement sandy soil are significantly influenced by the temperature, with frozen cement sandy soil exhibiting higher energy absorption efficiency.These findings provide a theoretical basis for the design and calculation of combined freezing and cement reinforcement techniques.