OVERVIEW

The course is focused on the analysis of the main ship structures in terms of loads and responses due to local and global actions and on their evaluation in terms of structural adequacy.

AIMS AND CONTENT

LEARNING OUTCOMES

The course aims at providing concepts and procedures for the identification of the main loads insisting on ship structures.

AIMS AND LEARNING OUTCOMES

After attending to the course, the student will be able to:

• Treat verbally, graphically and in written in a clear and logical form the subjects covered in the course and the inherent evaluation procedures  
• Identify a suitable structural model for the verification
• Identify the loads acting on the structure and their distribution
• Define the stress and strain state due to the loads
• Define the limit value of that state for the verification
• Define the possible changes (or the design choices) to be made to achieve the structural adequacy
• From a quantitative viewpoint, to compute, using simple models, loads, stresses static and dynamic responses of the global structure of the ship.  

PREREQUISITES

Basic scientific knowledge is needed to understand the course contents: mathematics, geometry, physics and chemistry.

Further, the contents of the following teaching modules is needed:

• Construction science
• Ship’s statics
• Geometry of floating bodies

In particular, the following specific knowledge is needed:

• Geometric characteristics of plane and volumetric figures: inertia and static moments definitions and computational capabilities
• Structural characteristics of materials for shipbuilding: Young’s modulus, Poisson’s coefficient, shear modulus, stress-strain diagrams, yielding stress, allowable stress, ultimate stress.
• Base concepts of stress-strain state analysis for a beam subjected to external forces (in particular an Euler beam)
• Capacity of interpreting the representation of typical ship structures (bottom, side, deck, bulkhead) following the course of Shipbuilding 1&2
• Hull geometry characteristics: Hydrostatic, Bonjean tables and operational knowledge of their use.
• Ship statics elements (floating body equilibrium: metacentric method, Euler theorem and inherent validity ranges)

TEACHING METHODS

Lectures and guided computer exercises begun in class under supervision of the teachers and completed autonomously

Students with valid certifications for Specific Learning Disorders (SLDs), disabilities or other educational needs are invited to contact the teacher and the School's contact person for disability at the beginning of teaching to agree on possible teaching arrangements that, while respecting the teaching objectives, take into account individual learning patterns. Contacts of the teacher and the School's disability contact person can be found at the following link Comitato di Ateneo per l’inclusione delle studentesse e degli studenti con disabilità o con DSA | UniGe | Università di Genova

SYLLABUS/CONTENT

• Primary, secondary and tertiary stresses in ship structures
• Hull girder scheme: characteristics and limitations
• Still water loads-quantitative example on a ship
• Example of pontoon with distributed and concentrated load
• Wave induced loads - general approach and quasi-static method
• Estimation of hull girder natural frequency
• Loads induced by launch, grounding, mooring and thermal actions
• Ultimate bending moment – concept and application to the Hull Girder
• Noise and vibrations propagation on board: sources, propagation path and receiving position - characteristics and limits

RECOMMENDED READING/BIBLIOGRAPHY

the slides used at lesson are available on Aulaweb and/or Teams

Further readings:

Ship Design and Construction – Thomas Lamb editor SNAME The Society of Naval Architects and Marine Engineers 601 Pavonia Avenue Jersey City, NJ

TEACHERS AND EXAM BOARD

LESSONS

LESSONS START

https://corsi.unige.it/8722/p/studenti-orario

Class schedule

The timetable for this course is available here: EasyAcademy

EXAMS

EXAM DESCRIPTION

Before the exam, students are requested to send the reports written on each exercise during the semester. They can be object of questions at the exam

The exam is composed of 2 parts:

Written part/numeric exercise (15 minutes)

Simple numerical exercise with determination and graphical representation of the distributions of actions, loads and stresses on pontoons loaded in different ways and possibly flooded or grounded or subjected to waves with simple geometry (quasi-static analysis).  Discouraged the use of computers. At the end the student will quickly explain orally procedure and results (5-10 min)

Oral part (about 30 min)

2-3 questions on any topic covered in the course and/or on the reports of the exercises carried out during the semester.

ASSESSMENT METHODS

During the exam the following items will be evaluated in general:

• The use of a suitable terminology in oral and written reports
• The correct choice and use of graphical means
• The logics in the sentences (correct cause-effect relation, capacity of distinguish input data, procedures and results)

In the written part the capacity of quantifying and represent graphically the results of the structural analysis will be evaluated, considering in particular:

• The coherence, also quantitative, between plots derived and data provided
• The coherence, internal to each plot and between plots
• The speed of computation

In the oral part the capacity of interpreting, describing, qualitatively identifying and orally reporting the results of the analysis of a scenario among those covered at lesson (ship still in calm water, ship in motion in rough sea, ship at launch or grounded, ship vibrating in calm water).

In particular the capacity of developing the following items will be evaluated:

• Interpretation of the physical situation
• Description of the forces acting on the structure: type, entity, distribution
• Choice of the structural model
• Identification of the loads acting on the structure and their distribution
• Define the stress-strain state in the structure
• Choice of the limit state for the check
• Identify the changes (or the choices) to be possibly made to obtain structural adequacy

In the analysis of the reports written in the semester, the abilities will be checked of identifying and reporting in written and in graphical form the results of the analysis. In particular, the following items will be evaluated:

• Knowledge of he text presented
• Clarity of the text: logics, completeness, concision
• Suitable and balanced use of graphical items: (tables, drawings, graphs) readability and clarity (number of significant figures, coherent and explicit measurement units)
• Clear identification and exploitation of results