Initial-stage abrasion rate of hydraulic concrete under submerged sand-laden jet impingement
Description
This study investigates the abrasion of hydraulic concrete under submerged conditions using the water-borne sand impact method. Experiments were conducted to examine the effects of impact time (0–8 h), angle (20°–90°), velocity (10–20 m/s), distance (0.1–0.3 m), concrete strength (C10–C40), and sand content (0–92.55 kg/m³) on the abrasion rate. Results show that abrasion evolves through three stages: an initial stage with nearly constant rate, a developmental stage marked by >20% rate reduction, and steady stage with negligible abrasion. During the initial stage, the maximum abrasion rate occurred at 60° due to the combined normal and tangential abrasion. Abrasion rate showed a strong linear correlation with sand content, confirming the dominant role of particle kinetic energy. A power-law relationship with velocity (exponent 2.96) was observed, where the sub-cubic exponent reflects a secondary but non-negligible contribution from water-phase stress. The abrasion rate peaked at an intermediate distance (0.2 m), driven by the trade-off between decreasing velocity and increasing impingement area. Tensile strength exhibited stronger correlation with abrasion resistance than compressive strength. An improved prediction model was developed by extending the classical framework to separately quantify particle and water flow contributions, account for velocity attenuation and expanding impingement area, and adopt tensile strength as the material parameter. Model validation using experimental and literature data showed over 85% prediction accuracy (mean relative error = 14.21%), outperforming two existing representative models by 12.61% and 10.73%. The findings offer mechanistic insights and a practical tool for design optimization and durability management in hydraulic structures.
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Institutions
- Tsinghua UniversityBeijing, Beijing