Drying-induced deformation behaviour of Shirahama sandstone in no loading regime

作者：Soe Aung Ko Ko^*; Osada Masahiko; Win Thandar Thetoe Nwe

来源：Engineering Geology, 2010, 114(3-4): 423-432.

DOI：10.1016/j.enggeo.2010.06.001

• Shirahama sandstone
• Evaporation
• Volumetric strain
• Shrinkage
• Matric suction
• Pore size

In this study, an attempt has been made to investigate the deformation behaviour of Shirahama sandstone in drying process using small cylindrical samples. A series of comprehensive laboratory experiments was performed in different drying conditions under a no applied load. Saturated cylindrical samples were dried in a climatic chamber while deformation and evaporative water loss were being monitored. The results obtained are reported and further used in linear poroelastic relation in order to derive the matric suction evolution. In addition, mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) were used for evaluating their pore structure and explained its role on measured strain and estimated matric suction. The results show that virtually no volume change occurs in the samples until half of the saturated water content is evaporated. It also reveals that the maximum dimensional change capacity is independent of drying condition but evaporation rate and strain occurrences are shown to be affected significantly. In addition, the study of pore structure indicates that substantial strain magnitude and high matric suction occurrence are attributed to water loss from small pores in the clay matrix. Throughout the process, the samples displayed neither a likelihood nor tendency of damage or destruction. However, strain magnitude is observed to be higher for the sample saturated with concentrated sodium sulphate solution. The present study sheds light on essential elements in the studies of dimensional changes of clay bearing sandstone to assist in evaluating ground movement, deterioration, fluid flow and isolation properties of underground facilities.

• 出版日期2010-8-10