ABSTRACT

Limited experimental data on the statistical distribution of the debris flow angles during flight required that certain assumptions be made at the outset of the transition to a probabilistic debris trajectory model. Due to the range of the flow angles as defined by Richards et al. (2008), it was assumed that the flow angles had an equal chance of occurring on either side of the mean as calculated by the deterministic debris trajectory model; therefore this warranted the assumption that the

1 INTRODUCTION

This paper presents a probabilistic debris flight trajectory model adapted from the deterministic 6-Degree-of-Freedom (6-DoF) model presented by Richards et al. 2008, in which both the aleatoric (inherent) and epistemic (knowledge-based) uncertainties will be considered in the proposed probabilistic model. While the inherent randomness (aleatoric uncertainty) in the debris flight trajectory is irreducible due to the wind turbulence, variation in wind direction, gustiness of the wind event and so forth, the proposed probabilistic model seeks to address these uncertainties through the application of the appropriate statistical methods. The proposed probabilistic model will provide an effective method for predicting debris trajectories in a three-dimensional (3D) space, which is imperative when performing regional building envelope impact risk assessment in which a large amount of debris sources and targets must be considered in the simulation.