Actual challenges for design and requalification of offshore structures through optimization and reassessment process draws attention to the importance of updating information about the structural safety. One of the most important phases during the design or re-assessment level is (re-)evaluation of environmental loads and resistance modeling concerning the state of bio-colonization, structural damage, and corrosion. The random nature of biofouling and the uncertainty inherent to biological processes make modeling of environmental loading complicated. Biofouling is a complex phenomenon involving a diversity of marine species which constitute communities whose growth dynamic is driven by physical and biological processes. It has many negative impacts on offshore structures such as loading excess, structures occlusion, increase in drag coefficient, and corrosion.
Therefore, it represents a challenge for engineers with respect to design and maintenance programs. Several standardized methods of inspections and in-situ measurements of the marine growth have been developed to obtain relevant information about species composition, percentage of cover, weight, average thickness and surface roughness allowing for the determination of structural design as well as establishment of cleaning and maintenance strategies. Biocolonization processes show spatial and temporal variations related to several environmental factors (water temperature, hydrodynamics, turbidity, distance from the shore, bottom characteristics, etc.) acting at regional and local scales.
However, the results are often more qualitative than quantitative and suffer of a lack of consistent modeling for structural engineers excepted when big data base are available. Cost-effective safety management of offshore structures involves allocating the optimal amount of resources to periodical inspections and maintenance activities in order to control risks (expected life of the structure). This workshop presents existing results and knowledge for this field of research where interdisciplinary is the key method. Methodologies for measurement and modeling are reminded and the lectures will highlight the main issues and remaining challenges. European researchers and specialists will address key questions.
This worshop is a WEAMEC (West Atlantic Marine Energy Center) event, within the COSELMAR project supported by the Research Institute of Civil Engineering and Mechanics (IUML - FR CNRS 3473) and the The Mer Bretagne Atlantique cluster and organized by IXEAD/Capacités, the subsidiary of Université de Nantes.