Meccanica Magazine n. 4

meccanica magazine
56
ENG
CONSTRUCTADD - Resource-efficient steel CONSTRUCTion using
ADDitive manufacturing
The interdisciplinary project EU-RFCS CONSTRUCTADD kicked-off
on 8 September 2022 in Milan, aiming to place the Metal Additive Manufacturing
(AM) in the mainstream of architecture and construction
by the year 2026.
Politecnico di Milano will coordinate the project with partners RWTH
Aachen University, Università di Pisa, Prima Additive, BLM GROUP,
FOMAS Group MIMETE, ArcelorMittal, Vallourec, IMDEA Materials
Institute, Cimolai Group, DNV. The project is funded by European
Research Executive Agency (REA) Research Fund for Coal and Steel
#RFCS (2022-2026). Polimi joins the project with two departments
namely Department of Architecture, Built Environment and Construction
Engineering and the Department of Mechanical Engineering.
The researchers of DMEC will contribute by coordinating the
activities in process and material development using a novel construction
steel grade for metal AM. In particular, the DMEC team coordinated
by Prof. Barbara Previtali and Prof. Ali Gökhan Demir will
develop the processes towards the production of full scale demonstrators
using metal AM with powder and wire feedstocks and laser
welding processes.
CONSTRUCTADD aims to bring metal additive manufacturing in the
mainstream of steel construction community by developing rules
and procedures and regulate it for sustainable steel construction
applications. Three Metal AM processes will be studied targeting
architectural engineering and construction industry: Laser Powder
Bed Fusion (LPBF), Laser direct energy deposition (LDED), Wire arch
additive manufacturing (WAAM).
The global objective of CONSTRUCTADD is to contribute to Europe’s
steel industry to start making full use of Additive Manufacturing (AM)
in the design, production and maintenance of complex and large
steel geometries to offer resource-efficient and reliable products
with reduced waste and energy consumption. To achieve the ambitions
of the project, specific objectives have been formulated:
- Define specific AM material and process rules for large parts on
quality, cost, processing, life cycle & recyclability, material safety
specifications and aesthetics;
- Selection of two powder and two wire feedstocks for production
as construction steel and quantify their processability with Laser
Powder Bed Fusion (LPBF), hybrid Laser Directed Energy Deposition
(LDED), and Laser Metal Wire Deposition (LMWD) in combination
with laser welding, and an innovative approach to Wire Arc AM
(WAAM) based on Cold Metal Transfer (CMT), quantify their recyclability
and mechanical properties;
- Design and produce demonstrator parts using the LPBF, LDED,
WAAM, and apply welding technologies with process parameters
defined in the project;
- Experimentally quantify the mechanical properties of 3D-printed
steel parts, and their structural integrity with the conventional steel
elements;
- Prepare the compliance route for construction parts produced by
AM, introduce qualification, standardization, and certification templates
compatible with EN1090, and propose modifications to the
existing European building standards and regulations using the new
experimental outcomes;
- Perform environmental and economic life-cycle analysis to establish
commercial and environmental benefits, and break-even points
for AM in steel industry;
- Transfer research results to Eurocode-compatible design recommendations,
guidelines and worked examples, to be used by the European
engineers, architects, and manufacturers;
- Disseminate and exploit the project findings in the EU construction
community to accelerate the acceptance of modern steel fabrication
approach studied in the project.
By exploiting the power of additive manufacturing, CONSTRUCTADD
will accelerate the transition of the steel construction sector toward
a sustainable production of structural systems. The project aims to
show that the sector can reduce the energy consumption of fabricating
a joint by approx. 30% and create less waste during fabrication,
than existing manufacturing methods. AM will also unleash the
sector from the constraints of traditional manufacturing and enable
mass customization with increased production speed and quality, by
placing materials where needed and using advanced digital tools for
design and production.
CONSTRUCTADD plans to reduce the energy consumption by means
of:
- Reducing the weight of critical complex parts while satisfying the
functional design requirements (e.g. strength, stiffness) with the
developed Structural Design for AM (SDfAM) approach;
- Customizing the joint geometries (shape and wall thickness) locally
to the internal stresses, moving the welds and the geometrical
discontinuities away from the geometrically complex regions to
be able to orthogonally bolt or weld them to the conventional steel
profiles, decreasing the material and energy use hence the costs,
and render the welds more accessible for periodic inspection and
maintenance.