Abstract

This research investigates the shrinkage behaviour of clay specimens subjected to different hydraulic paths. The volume change and microstructure of desiccated clay specimen directly dried from reconstituted slurry and compacted states, and the desiccated clay specimens obtained by subjecting the as-compacted clay specimen to cyclic wetting and drying process were compared. The experimental results showed that the initial microstructural difference between reconstituted slurries and compacted specimens influences their shrinkage behaviour. The compacted clay specimens retained the bimodal structure even after subjecting to cyclic wetting and drying, unlike the reconstituted slurry, which showed a predominant unimodal structure at the end of drying process. This is due to the absence of large macropores in the desiccated clay specimen dried from reconstituted slurry state, which is evidenced from the mercury intrusion porosimetry studies, scanning electron microscopy and nano-focus X-ray-computed tomography imaging experiments.

摘要

本研究调查了粘土试样在不同水力路径下的收缩行为。比较了从重组浆料和压实状态直接干燥的干粘土试样的体积变化和微观结构，以及对压实后的粘土试样进行循环润湿和干燥过程得到的干粘土试样。实验结果表明，重组浆料和压实试样之间的初始微观结构差异会影响它们的收缩行为。即使在经过循环润湿和干燥后，压实粘土样品仍保持双峰结构，这与重组浆料不同，后者在干燥过程结束时显示出主要的单峰结构。