On Characteristic Properties of Consolidation and Sterngth of Unsaturated Soils.

为了保证非饱和土建构筑物建成后的长期稳定性，有必要弄清非饱和土的固结和强度特性。从这一观点出发，通过试验研究了土壤的粒度分布、饱和度和干密度对土壤力学性质和土壤水分性质的影响。结果表明：(1)当饱和度较高或粒径分布较好时，压缩至恒定干密度所需的静应力较小；(2)在恒定干密度下，无侧限抗压强度在特定含水率下出现峰值。(3)在初始条件不变的情况下，无侧限抗压强度随土壤粘粒含量的增加而增加。(4)非饱和土的无侧限抗压强度与变形模数呈线性关系；(5)饱和度越高，或颗粒大小分布越好，24小时固结沉降量越大；(6)马砂土的渗透系数较高，初始沉降量与最终沉降量之比大于饱和土样；(7)土壤水分特征曲线受颗粒分布的影响较大，随粗粒含量的增加，水分特征曲线向含水率较低的方向倾斜；(8)恒定体积含水率随粘粒含量的增加而增大。

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.