Response-based reliability contours for complex marine systems considering short and long-term variability

Seyffert, Harleigh C.; Kana, A.A.

doi:10.1016/j.apor.2020.102332

Response-based reliability contours for complex marine systems considering short and long-term variability

Title

Response-based reliability contours for complex marine systems considering short and long-term variability

Author

Seyffert, Harleigh C. (TU Delft Ship Hydromechanics and Structures)
Kana, A.A. (TU Delft Ship Design, Production and Operations)

Date

2020

Abstract

Evaluating marine system reliability requires considering the interaction of a limit state with the stochastic ocean excitation. Given a range of operational profiles, a relevant question is which sea states lead to the worst-case system responses, considering the effects of short and long-term variability. If the identified subset of operational profiles indeed leads to the worst-case system responses, it is possible to assess lifetime system performance without unnecessary computational effort via this directed set of conditions. Environmental contour methods identify rare sea states assumed to excite rare responses but generally do not include response dynamics when choosing these sea states. For systems with limit states involving combined loading or with multiple failure modes, rare environmental conditions may not exclusively lead to rare responses. In this case, the response cannot be severed from the identification of relevant sea conditions but should instead drive that identification. This paper illustrates a way to construct response-based reliability contours that identify sea states most relevant for analyzing rare responses of marine systems. These sea states are compared with sea states identified by environmental contours, showing the effect on perceived system risk levels when system dynamics, short-term response variability, and long-term environmental variability are considered.

Subject

Combined loading
Environmental contours
Long-term environmental variability
Rare responses
Reliability
Response contours
Short-term response variability
Stiffened ship panel collapse

To reference this document use:

http://resolver.tudelft.nl/uuid:3ca71543-7de6-44c7-ab5d-98fa23dc89e5

DOI

https://doi.org/10.1016/j.apor.2020.102332

ISSN

0141-1187

Source

Applied Ocean Research, 103

Part of collection

Institutional Repository