Some ideas on constitutive modeling of debris materials

Abstract

Debris flows are dangerous natural hazards in countries with mountainous terrains. Debris materials show complex behavior depending on material composition and loading condition. Constitutive model plays an important role in better understanding the triggering mechanisms and reliable prediction of runout and deposition behavior. This paper reviews some constitutive models for debris materials in particular the Bingham fluid model. The hypoplastic constitutive model with critical state for granular materials is briefly recapitulated. Some ideas are presented to integrate the Bingham model into the hypoplastic constitutive model to account for both slow and fast flow of debris materials. The structure of this combined model and some specific formulations are discussed.