Resistance laws for debris-flow numerical simulation

Different theoretical approaches can be found in literature to describe the rheological behaviour of debris flows. These different approaches lead to the definition of different resistance laws that are then used in numerical simulations applied for hazard zoning and design of countermeasures. The performance of a simple resistance law is discussed in this paper, comparing the recorded and simulated dynamic characteristics of some debris flows monitored in the field. The theoretical approaches nowadays available to describe the theological behaviour of debris flows are not able to take into account all the complex processes that occurs inside the water-sediment current of a real debris flow. An interpretation based on the observations on some real and laboratory debris flows is proposed that confirms the applicability of the examined resistance law and the consequent approach used to describe the macroscopic behaviour of debris flows.