Structural Steel in a Circular Economy : Reuse of Load-bearing Steel Profiles within the Same Project
Year: 2026
Type: dissertation
Abstract: The construction industry in Sweden is currently responsible for about 22% of total greenhouse gas emissions. In addition to greenhouse gas emissions the industry produces large amounts of waste, which has increased the interest in reuse of building materials. Although reuse of structural components, such as structural steel, is a fairly new concept, it is now increasingly being requested by clients to built environment consultants, to reduce environmental impact. This study investigates the feasibility of in-house reuse of structural steel. In-house reuse refers to a concept in which the steel owner retains responsibility for storage and certification on site throughout the entire process. The study aims to investigate different opportunities and form a reuse process for a specific case with a certain client in mind.The study was conducted using a literature study combined with an interview study to an-swer questions related to the case study Övre Hallen. The scope was limited to the specific project in question, which adhered to Swedish laws and regulations. This regulated the scope of the calculations related to Global Warming Potential and cost calculations as well. Previ-ous research and results from the interview study indicated that over dimensioning is common when reusing structural steel. Therefore, the degree of utilization of the structure was analyzed, revealing that most of the investigated elements were over dimensioned. While reuse reduces the production of new steel, over dimensioning leads to inefficient material usage and limits the scrap material available to be utilized in a more effective way in other projects. Consequently, the study discusses reuse not only as a local strategy to reduce environmental impact, but also globally and in relation to material efficiency and optimization.Three different reuse processes were developed and evaluated. The first process was based on keeping the steel on site and reusing it in-house. The second process considered selling the steel to a steel distributor who manages certification and storage before it is bought back to the project. The third process was based on the idea to sell or recycle all profiles and replace them with smaller, more suitable profiles for the structural design. The result shows that the preferred process is highly dependent on the specific project, although in this case study the in-house reuse was found to be the most favorable choice. It enabled the largest amount of reused material 28.81% compared to 21.54% for the second process. The cost of 437 000 kr is comparable to the second alternative of 405 000 kr, and the greenhouse gas emission of 0.3 tons CO2e is the smallest compared to the second process of 0.5 tons CO2e.In addition, the study highlights challenges related to handling of inspection certificates and CE-marking documentation. The result shows that missing or incomplete documentation com-plicates the process of reuse and increases the need for additional testing. If inspection certificates are available the cost of a reuse process would be reduced. Therefore, the study concludes that an improved system for managing documentation is required to facilitate reuse of structural steel in the future.
Authors: Hedenlund, Polly, Hallgren, Karin
Language: English
Subfield: Strategy and Management
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W7213800924