Abstract: In the purpose of investigating the effect of treating soil erosion of purple soil slope by new water-soluble polyurethane (W-OH), we analyzed the impact of W-OH of 5% concentration on the processes of infiltration, runoff and erosion of purple soil slope under different rainfall intensities through indoor artificial rainfall experiment. We found that W-OH could remarkably enhance the erosion resistance of soil and reduce sediment yield on slope surface. Under test conditions of three different rainfall intensity (42, 72, and 112mm/h), the sediment yield on W-OH treated group declined by 89.40%-97.43%, and sediment transport rate by 86.67%-97.45% despite that runoff increased by 0.12-2.03 times compared with the control group. Under heavy rainfall(72 and 112 mm/h), the erodibility of W-OH treated soil reduced by 96.80%-97.41%. The conclusions offer theoretical basis and application guidance for the protection of purple soil slope.

Key words: W-OH, purple soil, infiltration, runoff and sediment yield, artificial simulated rainfall