Evaluating Constant Failure Rates in Storm Surge Barriers

Evaluating Constant Failure Rates in Storm Surge Barriers: A Statistical Framework Applied to Censored Component Lifetimes of the Oosterscheldekering

Epema, Jelle (TU Delft Electrical Engineering, Mathematics and Computer Science; TU Delft Civil Engineering & Geosciences)

Kok, M. (graduation committee)
Jongbloed, G. (graduation committee)
Chen, P. (mentor)
van Nooijen, R.R.P. (graduation committee)
Bakker, A.M.R. (graduation committee)
Mooyaart, L.F. (mentor)

Delft University of Technology

Applied Mathematics

2023-11-07

This study examines the validity of constant failure rates in the reliability assessment of storm surge barriers, with a focus on the Stormvloedkering Oosterschelde (SVKO). Analysing a dataset of 1,501 malfunctions, including 87 critical incidents over six years, we employ Exponential and Weibull statistical models to assess failure rates. The research question—whether the assumption of constant failure rates over time is valid—is addressed with a nuanced perspective. The findings in this study reveal that neither model conclusively fits all failure scenarios, with some data supporting constant rates and other data indicating variability. The Weibull model better describes certain scenarios, suggesting variable failure rates, while in other instances, both models show comparable performance. The p-values from hypothesis testing and visual inspection of component data provide inconclusive evidence, leading to the suggestion that both constant and variable failure rates may exist in storm surge barrier components. The research contributes to the field by challenging the prevailing assumption of constant failure rates, developing a statistical framework, and by suggesting the need for a flexible, scenario-specific approach to modeling failure rates for improved reliability assessments.

Lifetime estimation
Weibull distribution
Reliability analysis
Failure behaviour

http://resolver.tudelft.nl/uuid:77889376-31f1-4532-ab97-7c3ad46d6c8e

Student theses

master thesis

© 2023 Jelle Epema