集成回填材料的土水特征曲线测定

Experiment for the characteristic curve of soil water of integrated backfill material

以膨润土为基材,添加沸石、黄铁矿制备高压实集成回填材料,采用渗析法和汽相法分别测得其在不同温度及自由、侧限条件下的土水特征曲线(SWCC),并采用SWCC模型对实验数据进行拟合。结果表明:低吸力范围内,施加相同的初始吸力,最终测得50℃试样含水率>20℃对应含水率,原因是温度影响渗析法所测吸力值及试样饱和后的微观结构;高吸力范围内,同一吸力值80℃对应的含水率最小,土水特征曲线斜率随温度升高而增大。应力状态对土水特征曲线的影响,在低吸力范围内显著,而高吸力范围内则影响不大。这与材料的微观结构有关。Van Genuchten模型对实测数据的拟合效果最佳。

The highly compacted integrated backfill material is prepared by using bentonite mixed with zeolite and pyrite.The soil-water characteristic curve（SWCC） at different temperatures was obtained under different stress state by using osmotic and vapor phase technique.SWCC equations were used to fit the experiment data.The results show that water content reached at 50℃is greater than that at 20℃ at low suctions,when the same initial suction is imposed,which is caused by the effect of temperature on suction measured by osmotic technique and micro-structure of saturated sample.At a specific high suction,water content at 80℃ is the greatest,and the slope of curve increases with increasing temperature.In the range of low suctions,stress state has significant effect on SWCC,but has little effect at high suctions,which is related to the micro-structure of material.Results with the Van Genuchten model has a good fit for SWCC.