scope:

General

This Guide describes supplementary requirements for the application of higher-strength hull structural steel plates with or without specified brittle crack arrest (BCA) properties in container carriers with regards to the following:

• Hull structural design with higher-strength thick steel plates

• Requirements for H47 Non-BCA steels (H47 steels without specified BCA properties)

• Requirements for H36/H40/H47 BCA steels (H36/H40/H47 steels with specified BCA properties)

• Welding and fabrication of higher-strength thick H47 Non-BCA and BCA steel plates

• Prevention of fatigue and fracture failure of higher-strength thick steel plates

These requirements for thick steel plates are to be used in conjunction with the following ABS Rules:

• Part 5C, Chapter 5 "Vessels Intended to Carry Containers 130 meters (427 feet) to 450 meters (1476 feet) in Length" of the ABS Rules for Building and Classing Marine Vessels (Marine Vessel Rules) for the scantling and strength requirements.

• Chapter 1 "Materials for Hull Construction" of the ABS Rules for Materials and Welding (Part 2)

• Chapter 4 "Welding and Fabrication" of the ABS Rules for Materials and Welding (Part 2)

• ABS Rules for Survey After Construction (Part 7)

For thick steel plates in the upper flange of the hull structure, fatigue and fracture are two most pertinent failure mechanisms. When the hull girder strength is designed to meet rule minimum requirements, the accompanying effects of higher-strength thick steel plates are largely associated with higher stress levels and reduced fatigue and fracture strength characteristics. In the upper flange of the hull structure, wave-induced fatigue damages in way of thick plated weld connections are the first and foremost concern. As a countermeasure, the fatigue behavior of these weld connections is to be extensively evaluated to avoid initial crack initiation. Second, the presence of planar flaws in thick plated weld connections can adversely affect the integrity of these connections in the form of accelerated crack growth and fracture. Satisfactory fatigue and fracture characteristics are to be attained from improvements in structural design measures, steel materials, welding consumables, welding procedures and post-weld enhancements. Third, survey after construction is to be enhanced through monitoring critical areas and nondestructive inspection.