In a study on red soil engineering accumulations with gravel, scientists simulated rainfall to understand how it affects runoff and sediment loss. They found that heavier rainfall and more gravel caused faster runoff, but gravel didn't drastically impact runoff amount. Only when gravel content reached 10% did it noticeably affect runoff volume, peaking at a rainfall intensity of over 1.0 mm/min. Sediment concentration dropped initially, then stabilized. Higher gravel content reduced the impact of rainfall on sediment levels. Gravel notably decreased sediment loss at intensities greater than 1.0 mm/min. Overall, rainfall and gravel content were key factors influencing runoff and sediment yield on the engineering accumulations in red soil areas.