饱和粘土的一维热固结特性试验研究  

Experimental Study on One-dimensional Thermal Consolidation of Saturated Clays

作　　者：刘京铄[1] 范金星[1] 刘亚军[1] 

机构地区：[1]湖南水利水电职业技术学院水利工程系,长沙410131

出　　处：《湖南工程学院学报（自然科学版）》2016年第3期86-90,94,共6页Journal of Hunan Institute of Engineering(Natural Science Edition)

基　　金：湖南省教育厅科研资助项目(14C0746);湖南省水利厅重大科研课题(湘财农指[2010]29号;[2015]186号)

摘　　要：考虑温度对饱和粘性土的力学特性的影响,通过室内试验,研究了饱和粘土在不同温度作用下的固结效应;分析了温度引起的孔隙水压力以及渗透性差异性.试验表明,温度对土颗粒的膨胀作用和孔隙比的收缩作用影响较小.高温作用下发生的热膨胀在一定程度上阻碍了变形的发生,50℃条件下压缩指数较10℃条件下有减小的趋势.随着温度的升高,固结屈服应力均随之减小.温度越高,水溶液的粘度越低,越容易被排出,其渗透系数越大,超静孔隙水压的消散越快,所以50℃时的超静孔隙水压较10℃时小.渗透系数随着孔隙比的升高而升高.粒径较大的试样的渗透系数大于粒径较小的试样的渗透系数.Considering the effects of temperatures on the mechanical properties of the unsaturated cohesive soil, laboratory tests are conducted to investigate the consolidation effects of cohesive soils exposed to varying temperatures in the paper. The differences of pore hydraulic pressure and permeability caused by ternperatures are analyzed. By laboratory tests, consolidation properties of two saturated clays under different temperatures are studied. Results show that the effect of temperature on the expansion of soil particles and the contraction of void ratio is small; the thermal expansion due to high temperature can affect the deformation to some extent. So the compression index at 50℃ is smaller than that at 10℃. However, such an effect disappeared due to better permeability~ the consolidation yield stress decreases with increasing temperature. Higher temperature leads to less excess pore water pressure due to higher permeability coefficient because the viscosity of pore water at higher temperatures becomes weaker; permeability coefficient increase with larger void ratio and grain size.

关 键 词：饱和粘土 温度 热固结 孔隙水压 渗透性 

分 类 号：TU411.5[建筑科学—岩土工程]