ABSTRACT
Cement improvement method has been widely used for soft ground in Japan. One of the reasons is that compressive strength of the cement-treated soil can be controlled by amount of hardening agent. Recently, airformed lightweight soil has also been developed and mechanical properties of the lightweight soil have been investigated by many researchers (Omine et al., 2001, Watanabe et al., 1999, Yasuhara, 2002). Air-formed lightweight soil is usually made by mixing sand or original soil with water, hardening agent and air bubbles. The main features of the soil are i) lightweight (wet density between 0.6 and 1.2 g/cm3), ii) adjustable strength (unconfined compressive strength between 300 and 1000 kPa), iii) fluidity before hardening. However, those improved soils exhibit brittle behavior and low tensile strength. It is therefore that new geomaterial with toughness and frictional property is expected.
