人工冻融土物理力学性能研究

研究了原状土与人工冻融土的密度、干密度、含水量、饱和度、孔隙比、塑限、液限、塑性指数、液性指数、渗透系数等物理指标, 以及抗剪强度、无侧限抗压强度、压缩模量等力学指标的差异性. 土冻融后, 密度、干密度及塑性指数略有降低, 孔隙比、液性指数略有增大, 而其它物理指标基本一致. 粘土冻融后, 渗透性大大增加, 为原状土的～10倍, 而砂土仅略有增大. 粘土冻融后无侧限抗压强度是原状土的1/～1/2, 灵敏度降低, 其结果对冻结法向市政岩土工程的应用推广具有重要意义.

The Physical and the Mechanical Properties of Original and Frozen-Thawed Soil

Based on experiments, this paper deals with the differences of density, dry density, moisture content, saturation degree, porosity ratio, plastic limit, liquid limit, plastic index, liquid index, permeability coefficient and the differences of shear strength, unconfined compression strength, compressibility between original and thawing soil.When soil has suffered thawing, its density, dry density and plastic index decrease slightly, porosity ratio, liquid index increase slightly, and other physical index is constant on the whole. If the soil is clay, its permeability increases greatly, reaching 3～10 times of the original. If it is sand, the permeability less increases. The unconfined compression strength of thawing clay significantly decreases, reaching 1/3～1/2 of the original. To apply the frozen method to municipal rock engineering has bright foreground.