The EU aims to be climate-neutral by 2050, meaning an economy with net-zero greenhouse gas (GHG) emissions . With around 2.6 billion tons of CO2 emission (for production of approximately 1.9 billion tons), iron and steel has been the most pollutant bulk material produced on earth in 2020. Buildings and infrastructure account for around half of total steel demand. Iron and steel are responsible for about 8% of global final energy demand and 7% of energy sector CO2 emissions (including process emissions). The demand for steel is expected to increase continuously until 2050, however, at the same time, the steel industry must cut 50% of its CO2 emission by 2050 (compared to that in 2019) in order to fulfill the requirements for the net zero. The question here is how to answer the increasing demand in steel industry and at the same time decrease the GHG emissions until 2050 ?
In order to cope with this challenge, the International Energy Agency provides a series of strategies that can help to accelerate material efficiency and decrease the deman for production of new steel, including:
(1) retrofit/repair of structures to extend their lifetime,
(2) direct reuse (i.e., steel circular economy),
(3) development of lightweight and modular designs.
The above three strategies are the main research focus of the Sustainable Metallic Structures (SUMS) group at Empa. We develop various types of retrofit concepts to extend the lifetimes of metallic structures. This includes fundamental research related to fatigue and fracture behavior of steel, adhesives, and retrofit materials as well as development of repair systems (in close collaboration with our industry partners). The retrofit criteria, models and systems, which were developed at the SUMS group in the past years, have been used for repair and liftetime extension of different types of steel structures (e.g., steel bridges and building frames) around the world. Finally, by using new technologies such as additive manufacturing, we aim to design functional lightweight structures (via a computational design and optimization process) to achieve minimum waste of steel materials and a superior structural performance.
Current Research Projects
Shape memory alloys (SMAs) and fiber-reinforced composites (FRPs) for prestressed strenthening,
Fatigue and fracture in materials and structures,
Additive manufacturing (AM) for construction,
AM of lightweight lattice structures made of shape memory alloys (in collaboration with Empa Lab 204).