螯合飞灰在道路工程中的资源化利用可减少土地资源占用，但对其用作路基填料的可行性仍未形成统一的认识。本文通过室内试验和微观测试，研究螯合飞灰的基本物化特性和含水率、干密度对其工程特性的影响，探讨螯合飞灰用作路基填料的可行性，并提出施工控制指标和环境污染防治措施。结果表明：（1）螯合飞灰是一种微观结构复杂、比重较小的高液限粉土，相较于普通填料，最佳含水率偏大，最大干密度偏小；（2）螯合飞灰的主要化学元素为Ca、Na、Si、Cl，主要矿物成分为钙化合物、二氧化硅及氯盐，钙化合物可通过化学沉淀作用固化飞灰；（3）强度、有效黏聚力和有效内摩擦角分别随含水率和干密度的增加而近似线性下降和上升，渗透系数随干密度的增加呈下降趋势；（4）螯合飞灰适用于公路路基填料，用作路堤及路床填料的含水率范围宜为22.0%~29.5%和24.5%~29.5%。同时，为确保路基稳定和降低环境污染风险，建议采用低液限黏土包边和防渗土工布包芯联合处治。本文研究可为确定螯合飞灰路基填料的技术参数提供支撑，对其在道路工程的资源化利用具有重要的工程价值。

The resourceful utilization of chelated fly ash in road engineering can reduce the occupation of land resources, but there is no consensus of its feasibility as subgrade filler. Through indoor experiments and microscopic analysis, the physicochemical properties of chelated fly ash, as well as the influence of moisture content and dry density on its engineering characteristics, were investigated in this study. The feasibility of employing chelated fly ash as subgrade filler in highway construction was explored, accompanied by proposed construction control indicators and measures to prevent environmental pollution. The results show that: (1) Chelated fly ash is classified as a type of high liquid limit silt featuring a complex microstructure and low specific gravity, with a higher optimum moisture content and lower maximum dry density compared to common fillers. (2) The primary chemical elements in chelated fly ash are Ca, Na, Si, and Cl, with major mineral components including calcium compounds, silicon dioxide, and chlorides. Calcium compounds can solidify fly ash by chemical precipitation. (3) Strength, effective cohesion, and effective internal friction angle decrease approximately linearly with increasing moisture content, and increase with increasing dry density, while permeability coefficient decreases with increasing dry density. (4) Chelated fly ash is suitable for highway subgrade filler, with recommended moisture content ranges of 22.0% to 29.5% for embankments and 24.5% to 29.5% for roadbed materials. To ensure subgrade stability and reduce environmental pollution risks, it is recommended to employ low liquid limit clay cover and waterproof geotextiles core-wrapping for combined treatment. This study provides support for determining the technical parameters of chelated fly ash subgrade filler, and holds significant engineering value for its resource utilization in road engineering.

广西自然科学基金(2022GXNSFAA035485)；桂林电子科技大学研究生教育创新计划项目(2023YCXS189、2023YCXS193)