Committee V.2: Experimental Methods
Authors: Ehlers Soren , Abdussamie Nagi , Branner Kim , Fu ShiXiao , Hoogeland Martijn , Kolari Kari , Lara Paul , Michailides Constantine , Murayama Hideaki , Rizzo Cesare , Seo Jung Kwan , Kaeding Patrick 
Published: April 2023

Committee Mandate

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: best practice and uncertainty analysis; experimental techniques; full field imaging and sensor systems; big data applications for ship and offshore structures; and correlation between model, full-scale and numerical datasets.

Introduction

Design methods and rule requirements have to be benchmarked with experimental or service history data. The Goal Based Standards (GBS) approach by IMO, see e.g., IMO Res. 296(87), 454(100) or MSC.1/Circ.1394, require benchmarking of standards by measuring the performance of methodologies, assessments, criteria and requirements by using indicators that can be compared with an accepted standard or with experimental and/or service history data, performance levels or outcomes known to be reliable. This approach calls for a systemic use of experimental results and monitoring of data from ships during construction, in-service and possibly from the end of the life cycle. Thus, the elaboration of experimental outcomes and the handover of information into engineering and management practice need to be further addressed and standardized to fully exploit their potential.

Further, the continues growth of complexity in ship and offshore structures potentially designed outside the range of empirical references calls for reliable means of validation. While computer simulations are continuously improving at the same time, their improvement to a large extent depends on a physical understanding of the underlying phenomena to be captured. Therefore, experimental investigations are essential in driving further developments and innovations through their accurate feedback when performed correctly and meaningful. The latter is however challenging, especially with increased complexity of the phenomena to be investigated. Therefore, this report summarizes the expertise of the contributing authors with respect to their corresponding research fields. The report seeks to give a general overview of the specific experiments dealt with therein, presents the latest publications, possible obstacles to be addressed and closes with future recommendations for further developments and integration of the experiments into engineering practice and scientific developments.

The report at first covers a section on scaling laws relevant to any experiment followed by specific testing concerning: digital image correlation (DIC), hydrodynamics of flexible structures, wave-in-deck, hybrid models, friction, vibrations, fatigue at low temperatures, corrosion, large scale impact, large scale wind turbine blades, full-scale ice loads, health monitoring and digital twin models. Further, a benchmark study on free vibrations of a cantilever beam is carried out to demonstrate the vast possibilities to carry out such seemingly simple experiment followed by a discussion of the results achieved. The report is concluded with a summary and an outline of further research and development recommendations.