Development of a Probabilistic Framework for Debris Transport and Hazard Assessment in Tsunami-Like Flow Conditions

Abstract

In the past, hydraulic and structural design has predominantly relied on deterministic methods, often neglecting the stochastic nature that underlies transient loading processes. Nowadays, probabilistic design methods have gained wider attention. The accurate estimates of design conditions for structures must consider the probabilistic properties of the loads. One of the more challenging loads in extreme flooding events is related to debris transport and loading during hydrodynamic hazardous events. While it is crucial to assess damage on infrastructure as part of the design cycle, field surveys and numerical modeling provide little guidance as to how the motion of debris within these natural disasters can be adequately captured. This study examines an idealized case regarding the transport of debris during extreme flooding events, by evaluating the characteristics of shipping container motion entrained in a dam-break flow over a flat, horizontal bed. In aiding the promotion of probabilistic methods, this study proposes characteristics of the stochastic properties of debris transport, focusing on the lateral displacement and velocity of debris based on the experimental results. The magnitude of the lateral displacement was shown to strongly correlate with the local hydrodynamic conditions and the initial configuration of the debris. The results of the physical model were then incorporated into a probabilistic framework. The aim for developing this framework is to facilitate debris hazard assessment in extreme flooding event studies.