# Experimental Study on Scour Resistance Performance Enhancement of Chongqing Red Clay
## 3 Results and Discussion
### Anti-Dispersion Analysis  
The effects of curing agent dosage, cement content, and water-to-solid ratio on the anti-dispersion performance of solidified soil are shown in Figures 8-10, respectively, with turbidity levels of different mix proportions illustrated in Figure 11. As shown in Figure 8, curing agent dosage exhibits a significant positive correlation with anti-dispersion performance. When the curing agent dosage increases from 0% to 0.4%, the suspended solids content decreases sharply from 750 mg/L to 50 mg/L (a 93.3% reduction), and the pH value drops from 12.2 to 8.7 (a 22.3% reduction). This phenomenon may be attributed to the thickening and adsorption effects of the curing agent, which inhibit the migration and suspension of red clay particles, promote particle agglomeration and sedimentation, and consequently reduce suspended solids content. Additionally, the dense gel membrane  
Figure 6: The influence of cement dosage on fluidity. Figure 7: The influence of water solid ratio on fluidity. formed by the curing agent effectively encapsulates red clay particles, blocks water infiltration pathways, and slows the rapid dissolution of cement hydration products, thereby lowering pH values. Furthermore, as shown in Figure 11a, visual comparisons of different dosages demonstrate that increasing the curing agent dosage gradually clarifies the solidified soil-water interface and significantly improves water transparency, further confirming the enhanced anti-dispersion performance. Experimental results indicate that the curing agent dosage must reach a critical threshold to meet specification requirements. At a 0.2% dosage, the suspended solids content is 220 mg/L (46.6% exceeding the specification limit) with a pH of 9.3, approaching but still at risk of dispersion. Increasing the dosage to 0.3% drastically reduces suspended solids to 97 mg/L (35.3% below the limit) and stabilizes pH at 9.1, fully complying with specifications. However, at 0.4% dosage, the 1-h flowability of solidified soil is 150 mm, failing to meet construction requirements (\(\geq\)160 mm) and increasing project costs. Therefore, a curing agent dosage \(\geq\) 0.3% satisfies anti-dispersion specifications, while 0.3% optimally balances both performance and construction feasibility. Figure 8: The effect of curing agent dosage on anti-dispersibility. Figure 9: The influence of cement dosage on anti-dispersibility. As shown in Figure 9, when the cement content increases from 6% to 14%, the suspended solids content rises from 94 mg/L to 100 mg/L (a 6.4% increase), and the pH value slightly increases from 9.1 to 9.2 (a 1.1% increase), both remaining within specification limits. Figure 11b demonstrates that solidified soil samples with varying cement contents exhibit similarly clear soil-water interfaces and comparable water turbidity levels after immersion, showing no significant visual differences. This observation contradicts conventional understanding, where cement as a cementitious material is expected to enhance bonding strength and improve anti-dispersion performance with increased dosage. Potential explanations for this discrepancy include: (1) Cement hydration requires sufficient time to develop  
Figure 11: Comparison of suspended turbidity degree of solidified soil with different ratios. Each image is labeled with a corner indicating which group of experiments it belongs to. The three images in the row where each letter is located are the same set of experiments. Figure 10: The influence of water-to-solid ratio on dispersibility. effective strength, whereas anti-dispersion testing occurs within the initial 15 min before the initial setting, preventing the formation of spatial networks through hydration products like ettringite (AFt) and C-S-H gels to immobilize red clay particles. (2) Increased cement content proportionally raises mixing water demand under the fixed water-to-solid ratio, reducing slurry viscosity and marginally elevating suspended solids content.