Impact of Rock Fragment Shapes and Soil Cohesion on Runoff Generation and Sediment Yield of Steep Cut Slopes under Heavy Rainfall Conditions

The erodibility and erosion resistance of Quaternary sediments play a pivotal role in both the hydrologic processes soil cut slopes. To investigate runoff sediment yield slopes along Pai-Mo road, we performed indoor simulated rainfall experiments under 50° steep slope high intensity (120 mm/h), based on area’s climatic characteristics properties. included various rock fragment contents (30%, 40%, 50%), different levels roundness (i.e., rounded gravel, angular gravel), varying cohesion. results indicated that average infiltration rate uncemented gravel (URGSS) was higher than (UAGSS), resulting less delayed initial time. shear stress, power, drag coefficient, Reynolds number URGSS were smaller those UAGSS. In contrast, Froude flow velocity larger, stronger capacity. approximately two times UAGSS, cumulative about 20% higher. cemented (CAGSS) had larger rate, leading to yield. Overall, more shape radius curvature spherical particles resulted erosion, due local turbulence. Therefore, rill density alluvial greater colluvial heavy rainfall. Moreover, its strong cohesion, only raindrop splash inter-rill occurred moraine