【摘要】 土-水特征曲线是反映非饱和土基本特性的本构曲线,是土质斜坡非饱和渗流和力学机制分析中的重要参数。但受限于实验设备和测试技术等条件的限制,使得土-水特征曲线的测试耗时长、难度大,且多数测试方法难以实现全吸力范围内（0～10⁶kPa）的曲线测定,间接获取土-水特性曲线的模型拟合法,通常又存在因参数多解性而导致的结果失真等问题。现有的黄土高原非饱和特征曲线测试结果多集中于马兰黄土（L₁）,而其下的几十层黄土、古土壤的测试尚基本属于空白。笔者基于TRIM试验测试技术,对洛川黄土剖面的29层黄土-古土壤序列进行测试,获取了土-水特征曲线、吸应力特征曲线和渗透系数函数等系列参数,建立了黄土高原非饱和黄土工程特性标准剖面。通过对各参数综合分析发现,各物性参数在垂向上随深度呈现相似的变化规律,且均在黄土-古土壤的接触带参数变化较大;粘土矿物成分和孔隙结构特征是影响非饱和土-水特征曲线的重要参数,且与曲线参数α、n存在一定的非线性关系。更多还原

【Abstract】 Soil-water characteristic curve（SWCC）is the constitutive-curve to reflect the basic characteristics of unsaturated soil,which plays an important role in seepage and mechanical mechanism analysis for unsaturated slope.However,subjected to the limitation of experimental equipment and testing technique,it is usually time consuming and difficult to acquire the soil-water characteristic curves.It is difficult to acquire the SWCC in a whole suction range（0～10⁶ kPa）for the existing testing methods.Problems such as distorted results caused by multiplicity of inversion and interpretation are common.The existing tested SWCC are mainly focused on the Malan loess（L₁）,and the results for its following layers of loess and paleosol soil is almost blank.Take the Luochuan loess section at Yan’an city Shaanxi province as an example,the basic physical parameters,the material contents and the SWCCs have been experimented for the 29 layers of loess and paleosol soil by introducing the Transient Release and Imbibition Method（TRIM）technique has been introduced in this paper.And the standard profile for unsaturated engineering properties is established.Based on the comprehensive analysis of the parameters,it is observed that the different physical parameters of the soils at each layer change with depth similarly,and vary greatly at the transitional zone between loess and paleosol soil.Clay mineral contents and pore structure characteristics are two key factors affecting the SWCC,and they are nonlinearly corelated to the parameters ofαand n.更多还原