为探究部分颗粒流失对三峡库区易腐蚀紫色土压缩固结和渗透特性的影响,选用三峡库区易腐蚀紫色土进行一维固结压缩试验,设计不同干密度(1.50、1.45、1.39、1.34 g/cm3)和不同粒组缺失程度(无缺失、缺失小于0.075 mm粒组、缺失小于0.25 mm粒组、缺失小于0.5 mm粒组、缺失小于1 mm粒组)两组变量正交试验,并对试验数据采用4种类型的渗透系数–孔隙比非线性关系进行拟合。结果表明:(1)随着粒组缺失,不均匀系数Cu减小,平均粒径增大,压缩系数a1-2先减小后增大;(2)固结系数Cv1-2先减小后增大再减小,粗颗粒的骨架作用对粗粒土渗透系数也有重要的影响并且十分显著;(3)4种非线性渗透模型对三峡库区紫色土都是适用的,其中lg[k(1+e)]－lge渗透模型对试验数据拟合效果最好,相关度最高,且形式简洁。
In order to explore the effect of partial particle loss on the compression consolidation and permeability characteristics of the corrosion-prone purple soil in the Three Gorges Reservoir area, one-dimensional consolidation compression test was conducted on the corrosion-prone purple soil in the Three Gorges Reservoir area, with the design dry density of 1.50, 1.45, 1.39, 1.34 g/cm3 and the loss degree of different particle groups: No deletion, deletion less than 0.075 mm grain group, deletion less than 0.25 mm grain group, deletion less than 0.5 mm grain group, deletion less than 1mm grain group two groups of variable orthogonal test; Four types of nonlinear relation between permeability coefficient and pore ratio were used to fit the test data. The results show that: (1) With the absence of particle group, the inhomogeneity coefficient Cu decreases, the average particle size increases, and the compression coefficient a1-2 decreases first and then increases; The consolidation coefficient Cv1-2 firstly decreases, then increases and then decreases. The framework effect of coarse particles also has an important effect on the permeability coefficient of coarse particles. (2) The four nonlinear permeability models are applicable to purple soil in the Three Gorges Reservoir area, among which the lg[k(1+e)]－lge permeability model has the best fitting effect on the test data, the highest correlation degree, and the form is simple.
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