高庙子膨润土的土水特征曲线

近年来，用于高放废物深地质处置工程屏障的高压密膨润土越来越受到关注。经过全国范围内的比较和筛选，内蒙古兴和县高庙子膨润土矿床被确定为我国高放废物处置库缓冲材料的首选矿床。采用渗析法和水汽平衡法来控制吸力技术，通过上水特征曲线测定试验、环境扫描电镜和乐汞试验，研究高庙子高压密膨润土在不同吸力下的持水特性及其微观结构特征。利用压汞试验结果推算膨润土在恒体积条件下的土水特征曲线，并与实测数据进行比较。研究结果表明：在不同吸力作用下，膨润土的持水特性与其微观结构之间有着密切关系。

SOIL-WATER CHARACTERISTIC CURVES OF GAOMIAOZI BENTONITE

Attentions have been devoted in recent years to the behaviors of highly compacted bentonites used in engineered barriers for high level radioactive nuclear waste disposal. Througth a nationwide screening and comparison, Gaomiaozi(GMZ) bentonite deposit located in Xinghe County,Inner Mongolia,is considered as the first choice of Chinese buffer materials for high-level radioactive waste geological repository. A laboratory study has been carried out on compacted GMZ bentonite,including the measurement of soil-water characteristic curves(SWCC),the environmental scanning electron microscopy(ESEM) test,and the mercury intrusion porosimetry(MIP) test. The osmotic technique and vapour equilibrium technique were used for controlling suction. Comparison between the SWCCs of GMZ bentonite obtained from the MIP test results and the measured data under confined conditions is also made. Water retention properties bentonites of the GHZ under different suctions are related closely with to microscopic mechanisms.