腐殖质影响下高分解度泥炭土固化结构形成机制研究

滇池泥炭土具有高有机质的物质组成，疏松的海绵状结构形态，高分解度、大孔隙比的物理特性以及高压缩性、低强度的力学特征，将其作为承载地基须进行加固处理。然而，泥炭土孔隙结构的有效填充及腐殖质对水化反应的影响机制非常复杂，加固后的土体强度往往难以达到预期。为此，本项目在研究泥炭土腐殖质的物质组成、结合状态及主要活性官能团的基础上，揭示腐殖质与水化产物主要离子间的作用机制以及固化结构形成过程中主要离子的迁移和转化关系。研究腐殖质影响下固化土孔隙液主要离子浓度对水化产物的影响，探明固化泥炭土中胶结性水化物和膨胀性水化物的生成速率，确定两者间的协调关系及其在固化结构中的最佳组合，并构建高分解度泥炭土固化结构模型。基于物理模型试验测试加固泥炭土层的地基承载力，并建立相应的估算公式。本研究能够揭示腐殖质影响下高分解度泥炭土固化结构的形成机制，可以为该土层的加固决策提供关键科学依据。

Peaty soil in Dianchi Basin has the properties of high organic matter content, loose pore structure, high degree of decomposition, high void ratio, high compressibility and low strength, which must be stabilized when it is used as the bearing foundation. However, the effective filling of pore and the effect of humus on hydration are very complex, the strength of stabilized peaty soil is often difficult to achieve the expected. Therefore, based on the identification of material compositions, combination state and active functional groups of humus in peaty soil, this project will reveal the interaction mechanism between humus and main ions of hydrates, and elucidate the main ions migration during the process of the stabilized structure formation. The influence of the main ions concentration in pore fluid on hydrates will be studied under the effect of humus. The formation rate will be clarified for the cementitous hydrates and expansible hydrates, the coordination between them will be determined and the optimal combination will be pointed out. Then the stabilized structure model will be constructed for the peaty soil with high degree of decomposition. The bearing capacity of the stabilized peaty soil foundation will be test, and the corresponding estimation formula will be derived based on the physical model tests. This study can reveal the structure formation of stabilized peaty soil with high degree of decomposition under the effect of humus, and provide a critical scientific evidence for stabilizing peaty soil.