A numerical investigation of the interaction between debris flows and defense barriers

摘要

This paper presents some preliminary numerical results concerning the interaction between debris flows and defense barriers. Related simulations were carried out by employing a Computational Fluid Dynamics (CFD) commercial software. The approaching mass was treated as a single-phase equivalent fluid, obeying the generalized constitutive equation of Carreau. Defense barriers are structures typically placed where significant mass movements, in terms of volumes or velocities involved, are expected. They are designed to withstand debris flow impacts as well as to contrast local forces exerted by debris on the invested surface. Classical design methodologies are mainly based on the application of available empirical formulations, such as those adopted in EUROCODE standards. The proposed procedure yielded solicitations of magnitude usually lower than the corresponding obtained from classical approaches, hence potentially leading to the design of "less massive" works. Results, consisting of pressure fields and thrusts at the upfront barrier surface are discussed and compared with those ones derived from alternative methods.