0
research-article

EXTREME RESPONSE PREDICTION OF STEEL RISERS USING A FOUR PARAMETER DISTRIBUTION

[+] Author and Article Information
Miguel Alfonso Calderon Ibarra

Laboratory of Analysis and Reliability of Offshore Structures -LACEO, Civil Engineering Program - COPPE, Federal University of Rio de Janeiro, Centro de Tecnologia, Ilha do Fundão, 21945-970, RIO DE JANEIRO, BRAZIL
miguel@laceo.coppe.ufrj.br

Fernando Jorge Mendes de Sousa

Laboratory of Analysis and Reliability of Offshore Structures -LACEO, Civil Engineering Program - COPPE, Federal University of Rio de Janeiro, Centro de Tecnologia, Ilha do Fundão, 21945-970, RIO DE JANEIRO, BRAZIL
fjmsousa@laceo.coppe.ufrj.br

Luís Volnei Sudati Sagrilo

Laboratory of Analysis and Reliability of Offshore Structures -LACEO, Civil Engineering Program - COPPE, Federal University of Rio de Janeiro, Centro de Tecnologia, Ilha do Fundão, 21945-970, RIO DE JANEIRO, BRAZIL
sagrilo@coc.ufrj.br

Ying Min Low

Department of Civil and Environmental Engineering, National University of Singapore, Engineering Drive 2, E1A 07-03, Singapore 117576
ceelowym@nus.edu.sg

1Corresponding author.

ASME doi:10.1115/1.4041893 History: Received September 30, 2017; Revised October 19, 2018

Abstract

Short-term extreme response estimates are required in many areas of ocean and offshore engineering, such as steel risers design. As in many cases the response in non-Gaussian, a theoretical solution is usually not readily available for this purpose. Hermite transformation and Weibull-based models, among others, are some alternatives that have been used in connection with sampled response time series. In this work a new approach is investigated. Recently, a four-parameter distribution known as the shifted generalized lognormal distribution (SGLD) has been presented in the literature. One of its main advantages is that it covers regions of skewness-kurtosis not covered by other distributions of common use in engineering. In this paper, the performance of this distribution is evaluated in the extreme values' estimation of the utilization ratios of steel riser sections. Three alternatives for using SGLD are investigated in two case studies of different dynamic behavior. The first one is a SLWR (steel-lazy wave riser) connected to a turret-moored FPSO in 914m water depth, and the second is a SLWR connected to a spread-mooring FPSO in a water depth of 1400m. The results obtained by the SGLD-based analysis, which considered several simulation lengths, are compared to those obtained by means of an extreme value distribution fitted to episodical extremes obtained from many distinct realizations. The results of a traditional Weibull-fitting approach to the response peaks and those obtained with and Hermite transformation-based model are also presented for comparison.

Copyright (c) 2018 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In