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The Ship Structural Integrity Information System (SSIIS) project examines the development of a computerized information system that assists operators in the structural management of tank ships. The integration of information offers many advantages in the in the life cycle management of marine structures; supporting inspection planning, recording inspection results, designing repairs and analyzing failure trends. Reengineering is the redesign of existing information and work flows using information technology and organizational change. This report examines the reengineering of the structural inspection, maintenance and repair process to improve the integrity and quality of operating ships structural systems. This process is detailed and a prototype developed to demonstrate the applicability of these improvements.

This report is one in a series of reports conducted as part of a two year Joint Industry Research Project Structural Maintenance for New and Existing Ships initiated in June 1990 by the Department of Naval Architecture and Offshore Engineering of the University of California at Berkeley to both develop practical tools and procedures for the analysis of proposed ship structural repairs and to prepare guidelines for the cost effective design and construction of lower maintenance ship structures. This project was organized into six studies. This report is based on the results of Study 1 -- Fatigue Damage Evaluations whose objective is to develop and verify engineering guidelines for the evaluation of fatigue damage to critical structural components of existing ships. There are three reports. The first report addresses the fatigue reliability of welded details in tanker structures having multiple fatigue crack initiation sites. The second report includes a summary of the general fatigue life evaluation and fracture mechanics procedures, a description of the long term loading, a description of the uncertainties, and a description of the probabilistic and deterministic calculation procedures. The fatigue reliability model is extended to include the effect of inspection updating where not necessarily the whole structure considered is inspected in each inspection. The third report uses for two ship classes the integrated software package to analyze the fatigue damage for selected details and to compare the results with fatigue failure rate statistics obtained from data analyses of actual failure data.

This report marks the completion of the initial studies into a system to capture data necessary to perform analysis on failures in ship structures. It evaluates some existing ship database systems with the purpose to define guidelines for an improved, industry wide system. The system is anticipated to include information from design, construction, inspection, maintenance and operations. Particular emphasis has been placed on the capability of the system to produce Critical Area Inspection Plans (CAIPs) as defined by the U.S. Coast Guard. This report is the first year of what is intended to be a multi-year program. (MM)

This report is one in a series of reports conducted as part of a two year Joint Industry Research Project 'Structural Maintenance for New and Existing Ships' initiated in June 1990 by the Department of Naval Architecture and Offshore Engineering of the University of California at Berkeley to both develop practical tools and procedures for the analysis of proposed ship structural repairs and to prepare guidelines for the cost effective design and construction of lower-maintenance ship structures. This project was organized into six studies. This report is based on the results of Study 2 -- Corrosion Damage Evaluations whose objective is to develop and verify engineering guidelines for the evaluation of corrosion damage to critical structural components of existing ships. This report develops a rational approach to defining corrosion limits in tankers. The objective of this project was to make advances in the area of setting allowable limits for the wastage of tanker structures based on a procedure involving rational analytical techniques as an adjunct to the traditional, experienced based approaches.

Current developments in earthquake geotechnology in offshore structures are summarized. These developments include measurements of sea floor and platform motions induced by earthquakes and analyses of platform structure and foundation systems. Results from these recent developments are illustrated.

This Moderator's Report reviews the state-of-the-art report and papers submitted to the session on Offshore Earthquake Geotechnology. Selection of earthquake intensity and characteristics of ground motions for design of offshore structures, offshore source and attenuation characterizations, local site effects, and structure-foundation-soil interactions that may be exceptional to the offshore environment are discussed.