A serious threat to the long-term service performance of concrete protective structures is posed by debris flow, as a typical solid-liquid two-phase flow with high solid content, due to its strong impact and high abrasion characteristics. Based on field investigations, experimental studies, and mechanistic analysis, the abrasion behavior characteristics under the particle-slurry coupling effect in debris flows are investigated in this study, and the synergistic mechanisms of multiple abrasion modes, including particle impact, rolling cutting, and slurry scouring, are revealed. Through the investigation of typical debris flow protective engineering cases in the field , the abrasion damage patterns and evolution processes of concrete structures such as drainage channels and check dams are summarized. An anti-abrasion design system is proposed, which is composed of zonal fortification, material optimization, structural regulation, and surface protection. The differentiated protection is achieved through abrasion risk zoning, the impact resistance of the structural matrix is enhanced by using high-performance concrete and fiber-reinforced materials, structural cross-sections and flow patterns are optimized, and surface abrasion resistance is improved through coatings and biomimetic texture technology. A composite reinforcement method of matrix strengthening and surface wear resistance is established, along with surface protection design parameters. Theoretical basis and technical support for the anti-abrasion design of debris flow protective structures are provided by the results