Saliba N.E. A Quantitative Approach to Structural Forensic Engineering

Dissertation is submitted for the degree of Master of Engineering. — Montreal: McGill University, Department of Civil Engineering and Applied Mechanics, 2005. — 184 p.Structural forensic engineering is a topic that has traditionally been approached in a deterministic manner. This thesis explores the use of probabilistic procedures as a tool to obtain more objective and realistic results in forensic investigations. The first goal of the thesis is the identification of the most probable cause of a structural failure using probabilistic procedures. The second goal is to develop a procedure to qualify forensic engineers and experts according to their qualifications. In the first part, the basic qualifications required for a forensic engineer or expert are compiled in a checklist and attributed individual scores, the sum of which qualifies a candidate to act as a forensic engineer or expert. The proposed qualification and scoring checklist is then validated through a survey conducted among professionals with forensic engineering exposures. The second part quantifies failure modes in terms of their likelihood. The proposed methodology uses a-priori failure probabilities from historic data, elicits forensic engineering experts for subjective failure probabilities, calculates the updated posterior failure probabilities, and identifies the failure cause corresponding to the highest posterior probability as the most plausible cause of failure. The proposed methodology is supported by a thorough literature review of forensic engineering procedures, a classification of structural failure causes, and expert opinion elicitation and aggregation methods.