Temperature effects on the hydraulic behaviour of an unsaturated clay |
| |
| Authors: | E Romero A Gens A Lloret |
| |
| Institution: | (1) Geotechnical Engineering Laboratory, Department of Geotechnical Engineering and Geosciences, Technical University of Catalonia, Barcelona, Spain |
| |
| Abstract: | The influence of temperature on the hydraulic properties of unsaturated clays is of major concern in the design of engineered barriers in underground repositories for high-level radioactive waste disposal. This paper presents an experimental study centred on the investigation of the influence of temperature on soil hydraulic properties related to water retention and permeability. Laboratory tests were conducted on artificially prepared unsaturated fabrics obtained from a natural kaolinitic-illitic clay. Special attention is given to the testing procedures involving controlled suction and temperature oedometer cells and the application of the vapour equilibrium technique at high temperatures. Retention curves at different temperatures show that total suction tends to reduce with increasing temperatures at constant water content. Temperature influence on water permeability is more relevant at low matric suctions corresponding to bulk water preponderance (inter-aggregate zone). Below a degree of saturation of 75% no clear effect is detected. Experimental data show that temperature dependence on permeability at constant degree of saturation and constant void ratio is smaller than what could be expected from the thermal change in water viscosity. This behaviour suggests that phenomena such as porosity redistribution and thermo-chemical interactions, which alter clay fabric and pore fluid, can be relevant. |
| |
| Keywords: | permeability retention curve suction temperature unsaturated clay |
| 本文献已被 SpringerLink 等数据库收录！ |
