单一裂隙优势渗流对黏土层防渗性能的影响分析

发布时间：2018-05-03 03:20

本文选题：垃圾填埋体 + 压实黏土层　；参考：《岩土力学》2014年10期

【摘要】：垃圾填埋体不均匀沉降等容易引起压实黏土防渗层开裂,显著降低其防渗性能。将裂隙作为高渗透性的多孔介质材料,建立了含单一裂隙压实黏土层的饱和/非饱和渗流模型,数值研究了含裂隙黏土层中的优势渗流过程,对比分析了裂隙位置、深度、宽度和渗透系数对压实黏土层水分击穿时间和稳定渗漏量的影响。结果表明,含裂隙压实黏土层的渗流过程可分为3个阶段:初始阶段、击穿阶段和稳定阶段;底部裂隙对压实黏土层防渗性能的影响较小,而顶部裂隙和贯通裂隙的影响较大;水分击穿时间随裂隙深度增大而迅速缩短,为保证黏土层防渗性能,宜将裂隙深度控制在0.1倍土层厚度以内;水分击穿时间和稳定渗漏量随裂隙宽度、渗透系数的增大而分别缩短和增加,且当其达到一定值后逐渐趋于稳定;裂隙贯通后将显著降低压实黏土层的防渗性能,其稳定渗漏量随裂隙宽度和渗透系数的增大而呈线性增长。
[Abstract]:The non-uniform settlement of the landfill can easily cause the cracking of the compacted clay anti-seepage layer and significantly reduce its anti-seepage performance. A saturated / unsaturated seepage model with a single fissure compacted clay layer is established by using the fissure as a porous medium material with high permeability. The numerical study on the predominant seepage process in the fractured clay layer and the comparative analysis of the crack are made. The effect of gap position, depth, width and permeability coefficient on the water breakdown time and stable leakage of compacted clay layer. The results show that the seepage process of the compacted clay layer can be divided into 3 stages: the initial stage, the breakdown stage and the stable stage; the bottom fissure has little effect on the impervious performance of the compacted clay layer, and the top crack and through through. In order to ensure the permeability of clay layer, the fracture depth should be controlled within 0.1 times the thickness of the soil layer, and the water breakdown time and the steady leakage are shortened and increased respectively with the increase of the crack width and the permeability coefficient. Stability, fracture penetration will significantly reduce the permeability of compacted clay layer, and its stable seepage will increase linearly with the increase of fracture width and permeability coefficient.

【作者单位】：浙江大学
【基金】：国家重点基金研究发展计划(973计划)项目(No.2012CB719805)
【分类号】：TU46

【相似文献】