Debris-flow mechanics

Abstract

Debris flows involve gravity-driven motion of solid fluid mixtures with abrupt surge fronts, free upper surfaces, variably erodible basal surfaces, and compositions that may change with position and time. These complications pose great challenges in efforts to understand debris-flow mechanics and predict debris-flow behavior. Recently, however, a combination of observational, experimental, and theoretical research has begun to yield a coherent picture of debris-flow mechanics. To help build a foundation for future research, this chapter emphasizes principles of debrisflow mechanics that are relatively well established and also highlights areas where critical knowledge is lacking. The chapter does not provide a comprehensive review of debris-flow mechanics literature, which has become voluminous during the past decade.