Plant-based ecological protection is one of the effective methods to improve the stability of slope soils. However, plants need a stable growth environment and water supply. Although it has been demonstrated that polymer materials can effectively enhance the stability and water retention of soils, their improvement mechanism and long-term effects are yet to be clear. In this paper, we use a new polymer composite material (ADNB), an optimized compound of nano-aqueous binder (NAB) and super absorption resin (SAR), to conduct outdoor model tests to study the effects of different ADNB ratios on soil compactness, biochemical properties, and plant growth at longer time scales, and to explore its action law and mechanism of enhancing the ecological self-repairing ability of surface slope soil. The results show that ADNB can effectively improve the soil structure, increase the compactness of the soil, increase the organic matter content, microbial population and available nutrient content in the soil, thus promoting plant growth. The adsorption and agglomeration effect of the NAB in ADNB on soil particles and its degradation in natural environment can be observed by SEM. In summary, ADNB can not only effectively enhance the ecological self-repairing ability of surface slope soil, but also has good environmental friendliness and can be completely degraded under natural conditions without additional adverse effects on soil and environment.
Keywords: ecological self-repairing; long-term effect; model test; slope protection; soil improvement.