## 3 Results and Analysis  
### Influence of Ice Content on the Scraping Effect  
To quantitatively characterize the scraping patterns, the scraping characteristics of rock-ice avalanches were assessed by analyzing horizontal and vertical measurements \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Condition Name**} & **Initial Ice** & \multirow{2}{*}{**Ice Content(\%)**} & **Particle-to-Chute** & \multirow{2}{*}{**Particle-to-Chute** & \multirow{2}{*}{**Angle of**} & \multirow{2}{*}{**Flow Depth**} \\  & **Accumulation** & & **Bed Friction** & & **Sidewall Friction** & **Bepose/(\({}^{\circ}\))** & **/(m)** \\ \hline M-8 & Uniform & 80 & 18.5 & 23.2 & 25.7 & 0.073 \\ M-9 & Accumulation & 90 & 17 & 20.2 & 23.3 & 0.073 \\ M-10 & Uniform & 100 & 16.5 & 19.3 & 27.6 & 0.077 \\ IB-3 & Stones on Top & 30 & 21 & 18.5 & 26.9 & 0.059 \\ IB-4 & Stones on Top & 40 & 20 & 19.5 & 28.3 & 0.065 \\ IB-5 & Stones on Top & 50 & 20 & 18.9 & 28.1 & 0.072 \\  & of Ice & 60 & 18.5 & 21.1 & 26.2 & 0.067 \\ IB-6 & Stones on Top & 70 & 18.5 & 19.2 & 25.6 & 0.087 \\ IB-7 & of Ice & 30 & 24.5 & 23.1 & 27.7 & 0.054 \\ GB-3 & Ice on Top of & 40 & 25 & 24.1 & 24.8 & 0.054 \\ GB-4 & Stones & 50 & 25.5 & 23.2 & 26 & 0.066 \\ GB-5 & Ice on Top of & 60 & 25 & 22.5 & 24.1 & 0.063 \\ GB-6 & Ice on Top of & 70 & 26.5 & 23.6 & 21.4 & 0.067 \\ GB-7 & Ice on Top of & & & & & \\  & Stones & & & & & \\ \hline \hline \end{tabular} Note. The conditions in the table are labeled as follows: “M” represents uniform mixing, “IB” denotes ice on top and rock at the bottom, and “GB” indicates ice at the bottom and rock on top. The numbers represent the ice content by mass. For example, M-2 refers to a condition where the ice mass content is 20% and is uniformly mixed with gravel.  
\end{table} 
Table 2: _Cont._from the adhesive scales on the side panels of the lower chute following the scraping process. The scraping length is defined as the horizontal distance from the 0 mark on the horizontal scale (indicating the initial highest accumulation point of the base material) to the highest point of the base material accumulation after the scraping event. The maximum scraping depth is determined by subtracting the thickness at the lowest point of the base material post- scraping from the initial accumulation thickness (8 cm). Conversely, the minimum scraping depth is calculated by subtracting the thickness at the highest point of the base material from the initial thickness. The methodology for measuring these scraping characteristics is depicted in Figure 4.  
When the ice content is below 70%, both the scraping length and depth increase progressively with higher ice content. The scraping length peaks at an ice content between 70% and 80%, after which it begins to decrease as the ice content continues to rise. The presence of ice notably enhances the scraping length, increasing it by up to approximately 2.12 times, and the maximum scraping depth, by up to approximately 0.63 times (Figure 5). The relationship between scraping characteristics and ice content demonstrates that a certain proportion of ice enhances the scraping effect of rock-ice avalanches on the base material, with the most pronounced effect observed at 70% ice content. Figure 4: Schematic diagram of substrate accumulation: (**a**) before scraping; (**b**) after scraping. Figure 5: Effect of Ice Content on Scraping Effect: (**a**) relationship between maximum scraping depth and ice content; (**b**) relationship between scraping length and ice content. By comparing the scraping effects of the three initial accumulation forms, it is evident that the mixed accumulation form produces the most significant effect, whereas the \"ice on top of stones\" form results in the weakest effect (Figure 5(a,b)). Analysis of the scraping process in rock-ice avalanches indicates that the initial accumulation forms significantly influence the scraping effect by affecting the behavior of the leading material in the debris flow.