论文部分内容阅读
研究冻融循环作用对不同种类盐渍土抗剪强度的影响,对研究区域现场勘察取样,选取罗布泊地区两种典型天然盐渍土:氯盐渍土和硫酸盐渍土,分别配制最大干密度和最优含水率的试样,在不同冻融循环次数下进行三轴固结排水剪切试验,考察两类盐渍土的抗剪强度随冻融循环次数的变化关系。结果表明:氯盐渍土的抗剪强度参数c_d、φ_d随冻融循环次数的增加而减小,但φ_d降低的趋势比较平缓;硫酸盐渍土的抗剪强度参数c_d、φ_d随冻融循环次数的增加而减小;硫酸盐渍土的抗剪强度参数c_d、φ_d减小的幅度均大于氯盐渍土。氯盐和硫酸盐特性的不同是导致两类盐渍土抗剪强度随冻融循环次数增加而呈现不同变化趋势的根本原因。
The effects of freeze-thaw cycles on the shear strength of different types of saline soils were studied. Two typical natural saline soils, chloride saline soil and sulfate saline soil, were selected for site survey in the study area. The maximum dry density And the optimal moisture content of the sample under different freeze-thaw cycles under three-axis consolidation drainage shear test to investigate the two types of saline soil shear strength with the number of freeze-thaw cycles changes. The results show that the shear strength parameters c_d, φ_d of chloride saline soil decrease with the increase of the number of freeze-thaw cycles, but the tendency of φ_d decrease is gentle. The shear strength parameters c_d, φ_d of sulfate saline soil vary with the freeze-thaw cycles The decrement of the shear strength parameters c_d, φ_d of sulfate saline soil is greater than that of the saline soil. The difference between the characteristics of chloride and sulfate is the fundamental reason that the shear strength of two types of saline soils show different trends with the increase of the number of freeze-thaw cycles.