Ship Stability, Strength and Loading Principles

This is a clear and instructive guide to ship stability for anyone studying to become certified to Mate/Master or Officer of the Watch (OOW) level. It covers the ship stability syllabus requirements for learners studying for STCW 78 as amended for both OFFICER IN CHARGE OF NAVIGATIONAL WATCH REG and CHIEF MATE/MASTER REG. II/2 (UNLIMITED) certificate of competency. It also covers the principles of ship construction, to assist understanding of the nature of ship hull stresses in service. The text is extensively illustrated and supported by worked examples.

Part A of this book covers ship stability for the officer of the watch, providing an overview of the basic principles of ship stability, before introducing the hydrostatic data used to conduct loading calculations. To allow readers to compare certain hull shapes and ensure the preservation of adequate reserve buoyancy at all times, both the principal design coefficients and load line requirements are described. The vertical position of the ship's centre of gravity (G) and the factors influencing the position of the centre of buoyancy (B) are also discussed. This part also introduces the curve of statical stability, or GZ curve, and discusses the distinction between list and loll. To ensure that list is restricted to an acceptable limit, precautions for suspended weights are examined. Finally, this part examines the importance of trim when loading/discharging and ballasting the ship.

Part B considers ship strength and stresses, covering the classification of shipbuilding materials, ship stresses and structural strength compensation, shear force and bending moment calculations, and corrosion control.

Part C is aimed at mates and masters and provides comprehensive calculation procedures for trim, draught and load lines. It sets out the forces and stresses on a ship during dry-docking and explains the principles and procedures of the inclining experiment. It also looks at calculation of the angle of loll, factors affecting the shape of the curve of statical stability, wind heeling, heel when turning, calculation and assignment of freeboard, icing, bilging, and rolling and dangerous sea wave phenomena. Consideration is given to different types of cargo, such as bulk cargoes, grain and timber deck cargoes. Also included is the draught survey calculation procedure and assessment of compliance of the ship's loaded condition with MCA and IMO stability criteria.

The publication also includes worked examples for voyage planning and ship load calculations.

Reference is made throughout to procedures for verifying compliance with intact stability criteria and relevant regulations, conventions and codes of practice.

About the Author

Martin Rhodes, the author of this book, is a well-known lecturer on the subject of ship stability. The book is written in an accessible and easy to read style, guiding students through the subject in a logical manner.

About Witherbys

Witherbys titles are developed using scripts developed by technical experts that are peer reviewed within work groups. Typically, they seek to improve understanding of the regulations, recommendations and guidelines issued by Industry.

Witherbys staff have significant expertise in the fields of navigation and hazardous cargoes as well as in the presentation of complex subjects in a graphic and easy to understand manner.

Table of Contents

Part A SHIP STABILITY FOR THE OFFICER OF THE WATCH

• Chapter 1 Basic Principles
• Chapter 2 Hydrostatic Data – Draught, Displacement and Tonnes per Centimetre Immersion (TPC)
• Chapter 3 Design Coefficients
• Chapter 4 Load Lines
• Chapter 5 Centre of Gravity (G) and Centre of Buoyancy (B)
  • 5.1 Introduction
  • 5.2 Centre of gravity (G)
  • 5.3 Multiple weight problems
  • 5.4 Centre of buoyancy (B)
• Chapter 6 An Introduction to Transverse Statical Stability
• Chapter 7 Conditions of Stability
• Chapter 8 Initial Transverse Metacentre (M)
• Chapter 9 Free Surface Effect
• Chapter 10 The Curve of Statical Stability (GZ Curve)
• Chapter 11 List
• Chapter 12 Curves of Statical Stability for Different Conditions
• Chapter 13 Suspended Weights
• Chapter 14 Trim

Part B SHIP STRENGTH AND STRESSES

• Chapter 15 Shipbuilding Materials
• Chapter 16 Ship Stresses and Structural Strength Compensation
• Chapter 17 Shear Force and Bending Moment Calculations
• Chapter 18 Corrosion Control

Part C SHIP STABILITY FOR MATES AND MASTERS

• Chapter 19 Change of Trim due to Change of Density and Harder Trim Problems
• Chapter 20 Air Draughts
• Chapter 21 Dry-Docking
• Chapter 22 The Inclining Experiment
• Chapter 23 The Wall-sided Formula including Calculating the
• Chapter 24 Factors Affecting the Shape of the Curve of
• Chapter 25 Assessing Compliance of a Ship's Loaded Condition with MCA and IMO Stability Criteria
• Chapter 26 Bulk Cargoes and the Carriage of Grain
• Chapter 27 Calculation and Assignment of Freeboard
• Chapter 28 Stability Aspects of Timber Deck Cargoes
• Chapter 29 Wind Heeling
• Chapter 30 Icing
• Chapter 31 Draught Surveys
• Chapter 32 Heel when Turning
• Chapter 33 Bilging
• Chapter 34 Rolling and Dangerous Sea Wave Phenomena
• Chapter 35 Voyage Planning Calculations
• Chapter 36 Ship Load Calculations

Appendix Ship Stability Data Sheets