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温度影响着黏性土的液塑限、膨胀性和渗透性等水理性质,对于不同的黏性土,这种影响往往差异很大。为了系统地研究这一影响的规律性和机理,以南京地区3种不同矿物组分的黏性土为研究对象,开展了土样在5℃～50℃范围内吸附结合水量、液塑限、膨胀性和渗透性的试验研究。结果表明:温度升高时,黏性土液限减小,膨胀性增加,渗透性增加,这种温度效应根本原因在于吸附结合水量变化。亲水矿物由于其吸附结合水量大,对温度效应起主要作用。亲水矿物含量较多的黏性土,液限随温度变化大,而膨胀率则变化小。亲水矿物含量对渗透性的温度效应影响显著,对比吸附结合水试验:温度升高时,其渗透水由吸附结合水为主转为渗透结合水和自由水为主,渗透系数可上升近十倍。揭示了黏性土3种基本水理性质温度效应的规律性及机理,为相关的地质灾害的评估和预防提供理论基础。
Temperature affects the hydraulic and plastic properties of clay, such as liquid and plastic limits, expansibility and permeability. For different clay, this effect often varies greatly. In order to systematically study the regularity and mechanism of this influence, three kinds of cohesive soils with different mineral components in Nanjing area were studied. The adsorption-bound water content, liquid-plastic limit, Experimental Study on Expansibility and Permeability. The results show that when the temperature is increased, the liquid limit of clay decreases, the expansibility increases and the permeability increases. The fundamental reason for this temperature effect is the change of the amount of adsorbed water. Hydrophilic minerals play a major role on the temperature effect due to the large amount of water they adsorb. Hydrophilic mineral content of clay, liquid limit with temperature changes, while the expansion rate changes little. Hydrophilic mineral content has a significant effect on the temperature effect of permeability. Compared with the adsorption-bound water test, when the temperature is increased, the permeated water mainly changes from adsorbed bound water to permeated bound water and free water, and the permeability coefficient can increase nearly ten Times Reveals the regularity and mechanism of temperature effects of the three basic hydraulic properties of cohesive soil and provides a theoretical basis for the assessment and prevention of related geological disasters.