Measurements of suction versus water content for bentonite–sand mixtures

Abstract

Compacted soils have been widely used as landfill barriers because of favorable characteristics such as low coefficient of permeability and high swelling. Compacted bentonite–sand mixtures are normally unsaturated and therefore suction can be used as a behavioral indicator in addition to generally used factors such as water content and dry density (or void ratio). This study focused on investigating suction characteristics of bentonite–sand mixtures. Suction was measured using various techniques for compacted bentonite–sand mixtures. The laboratory results were analyzed to provide an understanding of the suction concept in expansive soils. It was found that suction depends primarily on the water content and the bentonite content of the mixture, and suction in expansive soils changes with the time of hydration.