【摘要】 为研究防渗用膨润土在寒旱区的适用性,对不同产地的3种膨润土的抗冻特性进行了研究。结果表明:水化液为黄河水31次冻融后,膨润土自由膨胀体积增加了32.8%,溶液电导率(EC)均值增加了27.7%,切应力增加了40.6%,滤出液累积量降低了23.5%,滤失量降低了23.4%,滤饼厚度降低了15.4%。方差分析可知,冻融循环对膨润土自由膨胀体积、溶液EC值、切应力、滤出液累积量均有极显著影响(F>F0.01)。冻融后膨润土微观结构参数变化范围为86.02～372.12μm,孔隙以板状及不规则孔隙为主,形态指标F值在0.12～0.40,孔隙表面分维在1.18～1.21。更多还原

【Abstract】 In order to investigate the applicability of watertight bentonite in arid and cold areas,the antifreezing properties of three kinds of bentonite,collected from different places,were studied.Results showed that,after Yellow River water was frozen and thawed for 31 timers,the free expansion volume,average EC value and shear stress of bentonite were increased by 32.8%,27.7% and 40.6%,but the cumulative filtrating volume,filtration loss and thickness of filtered bentonite cake were decreased by 23.5%,23.4% and 15.4 %,respectively.On the other hand,the results of ANOVA showed that the effects of freezing-thawing process on the free expansion volume,EC value of solution,shear stress and cumulative filtrating volume were significant(F>F0.01);the microstructure parameters of bentonite varied in a range from 86.02 μm to 372.12 μm,the pores were dominated by the plate and irregular shapes,the F value varied in a range from 0.12 to 0.40,and the fractal dimension of pore surface in a range of 1.18-1.21.更多还原