ABSTRACT
When designing steel components, the industrial cycle is important to consider. At present, iron production in blast furnaces and the recycling of steel scrap predominate. However, there is great potential in the reuse of components instead of recycling. To date, only a small amount of structural steel is reused. Many steel constructions are, e.g. due to serviceability requirements, requirements without making use of the plastic material reserves and the usual over-strengths with large safety margins. Currently, components are recycled despite high quality and good condition, instead of being directly reused. So far, concrete regulations are missing.
This paper presents first approaches for the development of regulations for the increased reuse of steel structures. There are already initial drafts for design standards that address the reuse of structural steel. Research approaches are concerned with defining the suitability of different components for reuse. It needs the development of evaluation criteria, evaluation categories as well as conformity testing of existing components. Possible is the definition of different component quality groups or a designation according to the traffic light system. A special focus should be placed on the safety of reused components. Furthermore, approaches to determine the environmental and economic benefits of reuse help to show the great potential of reusing steel components.
Additionally, components subjected to fatigue loading can be designed efficiently by constructing connections obtaining high fatigue classes, e.g. the machined butt joint. Alternatively, post-treatments methods like mechanical treatments or heat-treatment methods provide important tools to create extremely fatigue strength structural elements.
In the future, structured and consistent recommendations should be made for safe reuse of steel, for which the paper presents proposals.
