我国露天煤矿多处于季节性降雨明显和土层瘠薄的北方生态脆弱区，生态本底脆弱且土壤侵蚀严重。为了改善区内大型露天矿规模化开发引起土壤侵蚀和水土流失加剧的突出问题，提出采用壳聚糖联合脲酶诱导碳酸钙沉淀技术(EICP)对露天矿排土场边坡进行抗侵蚀改性。本研究通过不同温度与掺量下的EICP溶液试验，确定最优矿化反应参数，制备对照组、EICP和壳聚糖靶向诱导EICP三组边坡试样，通过边坡抗侵蚀相似模型装置分析边坡侵蚀状况、冲蚀量和表面强度变化规律，探究其对边坡抗侵蚀特性的影响规律。并对各组试样进行微观形貌、物相组成及热稳定性分析试验，探究壳聚糖联合EICP提高边坡抗侵蚀性的作用机理。结果表明：排土场边坡EICP抗侵蚀最优反应参数为尿素与氯化钙浓度1 mol/L、壳聚糖掺量5 g/L、温度不高于60 ℃；降雨侵蚀后，对照组分布不均匀表面凹坑，改性组则无明显变化，EICP和壳聚糖联合EICP组的最终土体冲蚀量分别降低了85.4%和91.6%，表面强度分别提高了9.8%、14.2%，EICP处理导致土体pH有所降低，而添加壳聚糖能够稳固脲酶活性进而保证尿素水解；壳聚糖分别通过静电作用和酸碱作用吸附脲酶与Ca²⁺为EICP提供成核位点，促进EICP稳态矿化产物(方解石)的生成并分散分布于土体颗粒间，且壳聚糖水凝胶与矿化产物都具有黏附、桥接和充填土体颗粒的固化作用，同时Ca²⁺可驱离强结合水降低颗粒间双电层厚度从而增强土体结构。结合室内试验与微观测试结果阐述了壳聚糖联合EICP技术提高边坡抗侵蚀性的有效性，揭示了其提高土体颗粒间联结力和减小坡面侵蚀力从而提高排土场边坡的抗侵蚀性的改性机制，研究成果有望对露天矿排土场边坡侵蚀防治技术的发展与工程应用提供有益借鉴。

Most of the open-pit coal mines in China are located in the ecologically vulnerable regions in the north with obvious seasonal rainfall and poor soil layer, where the ecological background is fragile and soil erosion is serious. To improve the outstanding problems of soil erosion and soil and water loss caused by large-scale development of open-pit mines in the region, it is proposed to use chitosan combined with urease-induced calcium carbonate precipitation (EICP) to modify the dump slope of open-pit mines for corrosion and resistance. resistance modification. In this study, the optimal mineralization reaction parameters were determined by testing EICP solutions at different temperatures and dosages. Three groups of slope samples were prepared: control, EICP, and chitosan-targeted-induced EICP, to analyze the erosion condition of the slopes, the erosion volume, and the change rule of the surface strength through the similar model device of the slope corrosion resistance, and to explore the influence of the corrosion resistance characteristics of the slope. corrosion resistance characteristics. The micro-morphology, physical phase composition, and thermal stability of each group of samples were analyzed to investigate the mechanism of chitosan combined with EICP to improve the corrosion resistance of slopes. The results showed that: the optimal reaction parameters for EICPcorrosion resistance of the slope in the drainage field were urea and calcium chloride concentration of 1 mol/L, chitosan doping of 5 g/L, and temperature not higher than 60 ℃; after rainfall erosion, the control group had uneven distribution of surface craters, while there was no obvious change in the modified group, and the final erosion amount of the soil in the EICP and chitosan combined EICP groups was reduced by 85.4% and 91.6%, respectively. and the surface strength was increased by 9.8% and 14.2%, respectively. EICP treatment led to the decrease of soil pH, while the addition of chitosan could stabilize urease activity and ensure urea hydrolysis; chitosan adsorbed urease and Ca²⁺ to provide nucleation sites for EICP through electrostatic and acid-base interactions, respectively, to promote the production and dispersal of the steady-state mineralization products (calcite) in the EICP and the distribution of the soil. Chitosan hydrogel and mineralization products have the solidifying effects of adhering, bridging, and filling soil particles. At the same time, Ca²⁺ can drive away the strongly bound water to reduce the thickness of the double layer between particles, thus enhancing the soil structure. Combined with the results of indoor experiments and microscopic tests, the effectiveness of chitosan combined with EICP technology to improve the corrosion resistance of slopes is explained, and the modification mechanism of improving the inter-particle bonding force of soil and reducing the erosive force of the slope surface so as to increase the corrosion resistance of dump slopes is revealed, and the results of the research are expected to be useful for the open-pit mine dump slope erosion control technology. The research results are expected to provide useful reference for the development and engineering application of open-pit mine dump slope erosion prevention technology.