On Characteristic Properties of Consolidation and Sterngth of Unsaturated Soils.

为了保持非饱和土结构在施工后的长期稳定，有必要明确非饱和土的固结和强度特征。在此基础上，以马萨土为试验材料，研究了土壤粒度分布、饱和度和干密度对土壤力学和水分特性的影响。得到了以下结果：(1)饱和程度越高，或粒度分布越好，压缩至一定干密度所需的静应力越小。(2)在一定干密度下，无侧限抗压强度在一定含水率下达到峰值。(3)土体初始条件一定时，无侧限抗压强度随粘土含量的增加而增大；(4)非饱和土的无侧限抗压强度与变形模量的关系与饱和土一样呈线性关系。(5)合并结算24小时。，饱和度越高，或粒度分布越好。(6)由于马萨土的渗透系数较高，其初始沉降与最终沉降的比值大于饱和土。(7)土壤水分特征曲线受粒度分布的影响较大，随粗粒含量的增加，土壤水分特征曲线向含水率较低的一侧筛分。(8)在一定pF条件下，土壤体积含水率随粘土含量的增加而增加。

To maintain the long-term stability after construction of unsaturated soil structures, it is necessary to clarify the characteristics of consolidation and strength of unsaturated soils. From such a viewpoint, the influences of grain size distribution, degree of saturation snd dry density of soils on the mechanical and soil moisture properties were investgated experimentally using Masa Soils.The following results were obtained.(1)The static stress required to compress up to a constant dry density was smaller, when degree of saturation was higher, or grain sizes had better distributions.(2)Under a constant dry density, unconfined compression strength showed the peak value at a specific moisture content.(3)when the initial condition of soil was constant, unconfined compression strength increased as clay contents of soil increased,(4)The relations of unconfined compression strength and modulus of deformation of unsaturated soil had linearity as well as saturated soils.(5)Consolidation settlements for 24 hrs.were larger, when degree of saturation was higher, or grain sizes had better distributions.(6)As coeffiicient of permeaqbility of Masa Soils was high relatively, the ratios of initial settlement to final settlement were larger as compared to those for saturated soils.(7)Soil moisture characteristic curves were greatly influenced by grain size distribution and their curves sifted to lower side of moisture contents with increasing coarse grain contents.(8)The moisture contents by volume at constant pF increased with increasing clay content of soils.