变孔隙条件下非饱和冻土渗透系数试验与分析

发布时间：2018-06-04 05:01

本文选题：含冰率 + 非闭合孔隙度　；参考：《哈尔滨理工大学学报》2017年03期

【摘要】：寒区土壤水文循环过程因冻土层的存在而复杂,冻土层中冰的存在使其水理性质变化引发许多特殊水文现象,在冻土水理性质研究过程中冻土渗透性研究是其中的关键问题之一。为了研究非饱和冻土含冰率和干密度对于非闭合孔隙度及其渗透性的影响,选取不同含冰率(2%、4%、6%、8%、10%、12%、14%、16%、18%、20%)、试样干密度(1.4×10~3kg/m~3、1.5×10~3kg/m~3、1.6×10~3kg/m~3)作为单因素变量,采用定水位达西试验方法分别进行冻土渗透系数测定试验,开展了非饱和冻土渗透系数测定试验研究。结果表明:非饱和冻土渗透系数及非闭合孔隙度随试样含冰率的增加而变小,随试样干密度增加而变小,变化范围为0.19-0.714及8.55-19.18 m/d。当含冰率为20%、试样干密度为1.6×10~3kg/m~3时得到最小非饱和冻土渗透系数为8.55 m/d,最小非闭合孔隙度为0.19。
[Abstract]:The process of soil hydrological cycle in cold region is complicated by the existence of frozen soil layer, and the changes of hydrological properties of ice in frozen soil layer lead to many special hydrological phenomena. The study of permafrost permeability is one of the key problems in the study of the hydrological properties of permafrost. In order to study the effects of ice content and dry density of unsaturated permafrost on the unclosed porosity and permeability of unsaturated permafrost, a single factor variable of 1.4 脳 10 ~ 3 kg / m31.5 脳 10 ~ 3 kg / m ~ (31.6 脳 10 ~ (3) kg / m ~ (3) was chosen as a single factor variable. The constant water level Darcy test method was used to measure the percolation coefficient of permafrost and the unsaturated percolation coefficient was studied. The results show that the permeability coefficient and unclosed porosity of unsaturated permafrost decrease with the increase of the ice content of the sample and decrease with the increase of the dry density of the sample. The variation ranges are 0.19-0.714 and 8.55-19.18 m / d. When the ice content is 20 and the dry density of the sample is 1.6 脳 10 ~ 3 kg / m ~ 3, the minimum permeability coefficient of unsaturated frozen soil is 8.55 m / d and the minimum unclosed porosity is 0.19.
【作者单位】：黑龙江大学寒区地下水研究所;黑龙江大学水利电力学院;中国科学院西北生态环境资源研究院冻土工程国家重点实验室;吉林大学环境与资源学院;
【基金】：冻土工程国家重点实验室开放基金课题(SKLFSE201310) 黑龙江省水文局项目(2014230101000411) 国家自然科学基金(41202171) 国家科技支撑计划(2014BAD12B01-03)
【分类号】：P642.14

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