Ebook: Proceedings of the 20th International Ship and Offshore Structures Congress (ISSC 2018) Volume 3

The 20th International Ship and Offshore Structures Congress (ISSC 2018) was held in (Liège) Belgium and Amsterdam (The Netherlands), 9–14 September 2018. The first volume of the proceedings contains the eight Technical Committee reports presented and discussed at the conference and the second volume contains the reports of the eight Specialist Committees. This third volume contains the Official discusser’s reports, written discussions and floor discussions, and the replies by the committees.

The Standing Committee of the 20th International Ship and Offshore Structures Congress comprises:

Chairman: Mirek Kaminski, The Netherlands

Co-chairman: Philippe Rigo, Belgium Segen Estefen, Brazil Neil Pegg, Canada Yingqiu Chen, China Jean-Yves Pradillon, France Patrick Kaeding, Germany Manolis Samuelides, Greece Stefano Ferraris, Italy Masahiko Fujikubo, Japan Rune Torhaug, Norway Carlos Guedes Soares, Portugal Yoo Sang Choo, Singapore Jeom Kee Paik, South Korea Ajit Shenoi, UK Xiaozhi Wang, USA

On behalf of the Standing Committee, we would like to thank the sponsors of ISSC 2018.

Mirek Kaminski, Chairman

Philippe Rigo, Co-chairman

Delft, 23 December 2019

Concern for descriptions of the ocean environment, especially with respect to wave, current and wind, in deep and shallow waters, and ice, as a basis for the determination of environmental loads for structural design. Attention shall be given to statistical description of these and other related phenomena relevant to the safe design and operation of ships and offshore structures. The committee is encouraged to cooperate with the corresponding ITTC committee.

Concern for the environmental and operational loads from waves, wind, current, ice, slamming, sloshing, green water, weight distribution and any other operational factors. Consideration shall be given to deterministic and statistical load predictions based on model experiments, full-scale measurements and theoretical methods. Uncertainties in load estimations shall be highlighted. The committee is encouraged to cooperate with the corresponding ITTC committee.

Concern for the quasi-static response of ships and offshore structures, as required for safety and serviceability assessments. Attention shall be given to uncertainty of calculation models for use in reliability methods, and to consider both exact and approximate methods for the determination of stresses appropriate for different acceptance criteria.

Concern for the dynamic structural response of ships and offshore structures as required for safety and serviceability assessments, including habitability. This should include steady state, transient and random response. Attention shall be given to dynamic responses resulting from environmental, machinery and propeller excitation. Uncertainties associated with modelling should be highlighted.

Concern for the ductile behaviour of ships and offshore structures and their structural components under ultimate conditions. Attention shall be given to the influence of fabrication imperfections and in-service damage and degradation on reserve strength. Uncertainties in strength models for design shall be highlighted. Consideration shall be given to the practical application of methods.

Concern for crack initiation and growth under cyclic loading as well as unstable crack propagation and tearing in the ship and offshore structures. Due attention shall be paid to the suitability and uncertainty of physical models and testing. Consideration is to be given to practical application, statistical description and fracture control methods in design, fabrication and service.

Concern for the quantification of general sustainability criteria in economic, societal and environmental terms for marine structures and for the development of appropriate principles for rational life-cycle design using these criteria. Special attention should be given to the issue of Goal-Based standards as concerns their objectives and requirements and plans for implementation. Possible differences with the safety requirements in existing standards developed for the offshore, marine and other relevant industries and of the current regulatory framework for ship structures shall be considered. Role of reliability-based design codes and requirements as well as their calibration to established safety levels.

Concern for the synthesis of the overall design process for marine structures, and its integration with production, maintenance and repair. Particular attention shall be given to the roles and requirements of computer-based design and production, and to the utilization of information technology.

Concern for accidental scenarios for ships and offshore structures and for their structural components leading to limit states. Types of accidental scenarios shall include collision, grounding, dropped objects, explosion, and fire. Attention shall be given to hazard identification, accidental loads and nonlinear structural consequences including strength reduction, affecting the probability of failure and related risks. Uncertainties in the use of accidental scenarios for design and analysis shall be highlighted. Consideration shall be given to the practical application of methods and to the development of ISSC guidance for quantitative assessment and management of accidental risks

Concern for advances in structural model testing and full-scale experimentation and in-service monitoring and their role in the design, construction, inspection and maintenance of ship and offshore structures. This shall include new developments in:

1. Best practice and uncertainty analysis

2. Experimental techniques;

3. Full field imaging and sensor systems;

4. Big data applications for ship and offshore structures

5. Correlation between model, full-scale and numerical datasets

The committee shall give an overview about new developments in the field of ship and offshore materials and fabrication techniques with a focus on trends which are highly relevant for practical applications in the industry in the recent and coming years. Particular emphasis shall be given to the impact of welding and corrosion protection techniques for structural performance, and on the development of lighter structures.

Concern for load analysis and structural design of offshore renewable energy devices. Attention shall be given to the interaction between the load and structural response of fixed and floating installations taking due consideration of the stochastic nature of the ocean environment. Aspects related to prototype testing, certification, marine operations and total cost of energy shall be considered.

Concern for structural challenges of non-conventional, special surface craft, including uncertainties in established design methods and modelling techniques. Particular attention shall be given to mega yachts, naval craft, offshore service vessels and work boats, which can be characterized by particular materials and structural configurations (wide openings, large unsupported structures, unconventionally shaped superstructures, etc.) and/or are to sustain specific loading conditions (harsh environment, severe cyclic loads or extreme operational ones).

Concern for development of technology of particular relevance for the safety of ships and offshore structures in Arctic regions and ice-covered waters. This includes the assessment of methods for calculating loads from sea ice and icebergs, and mitigation of their effects. On this basis, principles and methods for the safety design of ships and fixed and floating structures shall be considered. Recommendations shall also be made regarding priorities for research programmes and efficient implementation of new knowledge and tools.

Concern for the structural longevity of ship, offshore and other marine structures. This shall include diagnosis and prognosis of structural health, prevention of structural failures such as corrosion and fatigue, and structural rehabilitation. The focus shall be on methodologies translating monitoring data into operational and life-cycle management advice. The research and development in passive, latent and active systems including their sensors and actuators shall be addressed.

Concern for the safety and reliability of subsea production systems for offshore oil and gas. This shall include subsea equipment for production and processing, flowlines and risers, with emphasis to design, fabrication, qualification, installation, inspection, maintenance, repair and decommissioning. Structural design for flow assurance and safe underwater operations shall be considered.