78494 - MODELLING OF OFFSHORE STRUCTURES

Scheda insegnamento

Anno Accademico 2018/2019

Conoscenze e abilità da conseguire

In the course, element for modelling ofoffshore structures will be given. Three main parts of the course will be: equivalent static and dynamic modelling of the actions, including wave action and wind, both in the time and frequency domains; finite element modelling of the structure, stress and displacement recovery and verifications; modelling and verifications against cyclic loadings, with special emphasis to fatigue and damage of metallic materials.

Programma/Contenuti

Requirements/Prior knowledge
Fluent spoken English is a necessary pre-requisite: all lectures and tutorials, and all study material will be in English.

Course Contents
1. Introduction to structural solutions in the offshore environment
1.1 Platform typologies
1.2 Moorings
1.3 Pipelines

2. Environmental actions on offshore structures
2.1 Buoyancy and gravity
2.2 Fluid-induced structural forces (waves, currents and winds)
2.3 Earthquakes, ice impact and wave slamming
2.4 Deterministic and statistical descriptions of offshore waves

3. Dynamics of offshore Structures
3.1 Deterministic responses for single degree of freedom structures in time and frequency domain
3.2 Statistical responses for single degree of freedom structures
3.3 Responses of multi-degree of freedom linear structures

4. Finite Element Modelling of a fixed-bottom platform
4.1 Members, joints and mass modelling
4.2 Actions modelling (permanent loads, wind, waves and currents, soil-structure interaction)
4.3 Types of Analyses (static and quasi-static linear analysis, natural frequency, dynamically responding structures, non-linear analysis)

5. Fatigue assessment of offshore structures
5.1 Fatigue strength based on S-N curves
5.2 Damage accumulation rule and fatigue safety checks
5.3 Deterministic, simplified and spectral fatigue assessment methods
5.4 Stress concentration factor determination
5.5 Fracture mechanics approach

Testi/Bibliografia

  • Lecture slides and notes (available on the web site http://campus.cib.unibo.it [http://campus.cib.unibo.it/])
  • James F. Wilson, Dynamics of Offshore Structures, John Wiley & Sons, lnc., 2nd Edition, 2003. ISBN: 978-0471264675
  • Inge Lotsberg, Fatigue Design of Marine Structures, Cambridge University Press, 2016. ISBN: 978-1107121331
  • Guide for fatigue assessment of offshore structures, American Bureau of Shipping, 2003. Available at: https://www.eagle.org/eagleExternalPortalWEB/ShowProperty/BEA%20Repository/Rules&Guides/Current/115_FatigueAssessmentofOffshoreStructures/Pub115_FAOS
  • F. Tornabene, N. Fantuzzi, Theory of Laminated Composite Doubly-Curved Shell Structures, Esculapio, 2017. ISBN: 978-8893850018

During lectures, some reading assignments will be made from selected papers in the published literature.

Metodi didattici

The course content will be entirely covered by the lectures. The course includes some laboratory sessions, which will cover the practical aspects of the lectures. The instructors will tutor the students.

Modalità di verifica dell'apprendimento

A final oral examination is planned, based on questions intended to assess the knowledge and understanding of the topics covered by the course. Furthermore, the student should present and discuss the solutions of some homework assignments.

The assessment of the "expected learning outcomes" is composed of:

  • Discussion on homework assignments (up to 10 points).
  • Oral composed of 3 questions (8 points each, up to 24 points).

To obtain a passing grade (minimum is 18 points**) students are required to demonstrate a knowledge of the key concepts of the subject, some ability for critical application, and a comprehensible use of technical language. Higher grades (maximum is 30 points, cum laude) will be awarded to students who demonstrate an organic understanding of the subject, a high ability for critical application, and a clear and concise presentation of the contents.

** in case of failure students can take any next final term, generally there are 6 final terms per academic year.

Strumenti a supporto della didattica

The teaching tools are overhead projector, projector and PC.

Link ad altre eventuali informazioni

http://www.dicam.unibo.it/

Orario di ricevimento

Consulta il sito web di Nicholas Fantuzzi