Abstract
To precisely express contamination phenomena of shallow ground caused by Non-Aqueous Phase Liquids (NAPLs), a multiphase seepage analysis based on a characteristic curve model considering properly a water-NAPL-air three-phase retention property of soil is necessary. In previous research, the model proposed by Lenhard & Perker has been used for water-NAPL-air three-phase coupled seepage analysis. However, regarding soil pollution problems in which a thin layer of NAPL exists in the ground, previous studies showed that the model cannot be applied. Nakamura and Kikumoto solved the problem by the formulation of a new characteristic curve model based on a state variable μ but their new model assumed the unique relationship between suction and degree of saturation. Therefore, it cannot consider hysteretic phe-nomena. In this paper, we propose a new model by introducing a new state variable representing water and liquid phase run to consider the hysteretic phenomena. The model is validated by a simulation of the three-phase column test.
