中文摘要：

以全风化泥岩为研究对象,采用压力板法、滤纸法和饱和盐溶液蒸气平衡法3种方法研究在全吸力范围内压实样的脱湿阶段持水特性;压汞试验测试土样的孔径分布,来解释宏观持水现象,并用此分布曲线推算持水曲线;利用瞬态吸湿脱湿系统(TRIM)快速测量土水特征曲线;以Brooks&Corey、Van Genuchte和Fredlund&Xing模型为基础进行预测,比较了拟合结果。试验结果表明:全风化泥岩压实样的进气值约为75 k Pa;与经典的持水曲线不同,过度段不是一条直线,中间出现了水平台阶状。基于瞬态理论的TRIM测试方法可以较好地对持水性进行预测。此外,饱和样为单峰孔隙结构,经受过吸力38 MPa的土样为双峰孔隙结构;饱和样孔隙的孔径主要集中在102~103 nm左右,随着吸力的增加,这个孔径范围的孔隙量减少最大。Van Genuchte和Fredlund&Xing模型拟合曲线能很好地与试验数据吻合;其它预测持水曲线在很干和近饱和的状态与试验数据有一定的偏差。

英文摘要：

The pressure plate method, filter paper method, vapor equilibrium technique with saturated salt solution, transient water release and imbibition method and mercury intrusion porosimetry (MIP) tests are used to investigate the water retention behaviour and pore-size distribution of compacted complete-intense weathering mudstone specimens taken from Cenxi, Guangxi Province. Based on the results of the MIP tests experiencing two different suctions, a method for predicting the water retention curve is proposed. The test results show that the air entry value of complete-intense weathering mudstone is about 75 kPa, and the water retention curve in the full suction range can be measured by the three methods. There appears a plateau stage in SWCC. The SWCC calculated by TRIM matches the results of conventional tests. The saturated specimen exhibits a unimodal pore-size distribution, and the specimen experiencing suction of 38 MPa has a double-porosity microstructure. There are mainly intergranular pores with diameter of 102 nm to 103 nm in compacted samples of complete-intense weathering mudstone. With the increase of the suction, the pores in this diameter range decrease. The SWCCs fitted by Van Genuchte and Fredlund & Xing are more close to the measured results accurately, and those fitted by other models cannot match the measured water retention curve correctly in the full suction range.