真空预压-电渗联合作用下长三角滩涂软土固结特性

    Research on the consolidation characteristics of soft clay under combined vacuum preloading-electroosmosis treatment

    • 摘要: 针对长三角滩涂软土地基,采用真空预压-电渗联合加固工艺以加速土体固结。通过现场监测与室内土工试验,深入分析了在短历时真空负压与直流电场共同作用下,淤泥质软土的快速固结过程及其工程特性演变规律。结果表明,阴阳电极所形成的排水边界条件使真空渗流场成为主导渗流路径,导致电渗对孔隙水压力与地表沉降的直接贡献较为有限。然而,在真空渗流、电渗流、电化学作用及热温效应的多场耦合影响下,高塑性、低渗透性的细颗粒淤泥质软土,其物理性质、变形特性与强度指标之间的内在关联被重构,且相关性显著增强。进一步分析发现,土体强度的提升主要源于内摩擦角的增大,而黏聚力的贡献相对较小。

       

      Abstract: This study investigates the combined vacuum preloading and electro-osmosis technique to accelerate the consolidation of soft dredged clay in the Yangtze River Delta. Field monitoring and laboratory tests were conducted to analyze the rapid consolidation process and the evolution of engineering properties under short-term vacuum pressure and direct current. The results indicate that the drainage boundaries established by the electrodes allowed the vacuum flow to dominate the seepage path, thereby limiting the direct contribution of electro-osmosis to pore water pressure dissipation and surface settlement. However, under the coupled effects of vacuum seepage, electro-osmotic flow, electrochemical reactions, and thermal activation, the intrinsic correlations among the physical properties, deformation characteristics, and strength indices of the high-plasticity, low-permeability silt were reconfigured and significantly enhanced. Furthermore, the improvement in soil strength was primarily attributed to the increase in the internal friction angle, with cohesion playing a comparatively minor role.

       

    /

    返回文章
    返回