李华,李同录,张亚国,李萍,范江文.不同干密度压实黄土的非饱和渗透性曲线特征及其与孔隙分布的关系[J].水利学报,2020,51(8):979-986 |
不同干密度压实黄土的非饱和渗透性曲线特征及其与孔隙分布的关系 |
Relationship between unsaturated permeability curve and pore-size distribution of compacted loess with different dry density |
投稿时间:2019-10-07 |
DOI:10.13243/j.cnki.slxb.20190680 |
中文关键词: 压实黄土 渗透性曲线 干密度 孔隙分布 |
英文关键词: compacted soil permeability curve dry density pore-size distribution |
基金项目:国家自然科学基金项目(41790442,41772278) |
作者 | 单位 | E-mail | 李华 | 长安大学 地质工程与测绘学院, 陕西 西安 710054 黄土高原水循环与地质环境教育部野外科学观测研究站, 甘肃 正宁 745399 | | 李同录 | 长安大学 地质工程与测绘学院, 陕西 西安 710054 黄土高原水循环与地质环境教育部野外科学观测研究站, 甘肃 正宁 745399 | dcdgx08@chd.edu.cn | 张亚国 | 黄土高原水循环与地质环境教育部野外科学观测研究站, 甘肃 正宁 745399 长安大学 建筑工程学院, 陕西 西安 710054 | | 李萍 | 长安大学 地质工程与测绘学院, 陕西 西安 710054 黄土高原水循环与地质环境教育部野外科学观测研究站, 甘肃 正宁 745399 | | 范江文 | 长安大学 地质工程与测绘学院, 陕西 西安 710054 黄土高原水循环与地质环境教育部野外科学观测研究站, 甘肃 正宁 745399 | |
|
摘要点击次数: 2847 |
全文下载次数: 794 |
中文摘要: |
压实黄土在水分入渗条件下容易产生湿陷、不均匀沉降等工程地质问题,因此有必要对其渗透特性进行研究。本文采用基于滤纸法的竖直土柱试验测试了3种不同干密度压实黄土全吸力范围的渗透性曲线。试验结果表明,压实黄土的渗透性曲线随着基质吸力减小分为缓升段、陡升段和饱和段三个阶段,且干密度越小的土三段特征越明显。压实黄土干密度的差异主要影响低吸力段渗透系数,干密度越大,渗透系数越小;基本不影响高吸力段渗透系数。由于渗透系数与孔隙分布密切相关,孔隙越多渗透性越强。因此本文用压汞试验测得了3种土样的孔隙分布曲线。试验表明不同干密度的压实黄土,微孔数量基本相同,对应吸力范围的渗透系数也相同;孔径为1.3 μm < d < 8 μm的小孔数量随干密度增大而减小,对应吸力范围的渗透系数也相应地减小;中孔、大孔数量很少,其对土样的渗透性的影响甚微。这反映了渗透性受孔隙分布控制的内在机理。 |
英文摘要: |
Water infiltration may induce collapse and differential settlement in compacted loess area, therefore, it is necessary to study its permeability characteristics. The permeability curves of compacted loess with three different dry density are measured by a vertical soil column with filter paper. The results show that with the decrease of matric suction, the permeability curve of compacted loess can be divided into three stages:slow increasing, quick increasing and saturated, and the smaller the dry density is, the more obvious the characteristics of the three stages would be. The variable of the dry density affects the permeability on low suction range, the larger the dry density, the smaller the permeability coefficient. The variable of the dry density doesn't affect the permeability on high suction range. In addition, it's well known that the more the pores in the soil, the larger the permeability. Therefore the pore-size distributions of the three soils are measured by mercury intrusion porosimetry tests. The results show that the amount of micro pores is the same between loess with different dry density, the corresponding permeability are the same too. The larger the dry density,the less the small pores (1.3 μm < d < 8 μm),and the smaller the corresponding permeability. Middle and large pores make little influence to the permeability due to its low content. |
查看全文
查看/发表评论 下载PDF阅读器 |
关闭 |
|
|
|