Modular RoRo deck

Modular decks for RoRo vessels (non-metallic)

Custom-made hull

Custom made hull for offshore vessel

Fully outfitted and modularised cabin

Multi material lightweight cabin for passenger ships

Panel system (bio-based and other)

Lightweight components for high loads and fire class

Composite block on steel deck

Composite superstructure module on steel deck for multi purpose vessels

Versatile walls

Integration of system for internal walls and superstructure
of cruise ships into shipyard processes

Lightweight rudder flap

Lightweight rudder flap

3D-printed propeller blade

Propeller blades by additive manufacturing

Panel system (truss structure)

Modular light system for less critical internal walls and superstructure

Aluminium composite panels

Lightweight aluminium and composite walls for work boats

High tensile steel decks

Lightweight decks using high tensile steel in cruise ships

Design details (high tensile steel)

Highly loaded structural details from high tensile steel
in passenger and research vessels

Patch repair - composite overlays

Composite overlay to repair and improve metallic and
non-metallic structures

RoRo deck

custom-made hull

cabin system

aluminium panels


versatile walls

rudder flap

propeller blade

truss structures

bio-based panels

steel decks

steel details

patch repair

Composite overlay to repair and improve metallic and non-metallic structures

State of the Art

The particular potential lies in the fact that composite patch repair is a comparatively easy-to-apply, robust and cheap method to extend the lifetime of many applications, within and beyond the maritime sector. Methods to strengthen and improve critical joints are already in use in other transport modes, but are new for the maritime sector, partially owing to the need for worldwide application, extreme environmental conditions and lacking long-term experience.


Demonstrate that composite overlaminate is suitable both as repair technology for damaged structures in a marine environment to improve the pristine properties of welded joints.


Innovative repairing solutions to metal and composite marine structures as well as reinforcement composite solutions were be developed to be applied over steel welds, in order to improve their in-service behaviour, preventing fatigue damage. This involved the study of three different demonstrator cases regarding composite overlamination techniques: the use of composite patches for crack repairing in structural details of a cruise ship; the use of overlamination techniques for repair and reinforcement of joints applied to a hull section for a large offshore vessel; and composite overlamination techniques were studied and applied to reinforce welded HSLA steel joints, with the aim of improving their fatigue life.

For the demo cases, the composite patch design, calculation of fracture parameters and the patch design refinement based on the analysis of the results was done. More precise development of the FEA (finite element analysis) models was done and fed by composite materials characterization data, thus the selection of the optimal composite system and the configuration of the patch (number of layers, fibre orientations, etc) was defined. The fracture parameters at the crack tip were evaluated to analyse the effectiveness of the selected patch. For process engineering, the trials for different surface condition, composite specimens characterization and single lap joint test has been performed.


This results in weight savings of up to 20% and reduced lead-time. Further expected impacts, composite overlamination may become a valuable method to assist various lightweight applications in different materials.