Produktionstekniska aspekter på återbruk av betongelement

Sammanfattning: The EU has established a binding target to reduce CO2 emissions by 40% by 2030, Sweden has taken one step further and has decided to be carbon neutral by 2045. 7 % of the world´s total CO2 emissions comes from concrete production which makes it a field with great potential to improvement. The purpose of this study was to evaluate the requirements for reusing concrete elements in practice in the construction of new buildings. This was done by evaluating obstacles in construction for reused concrete elements and investigating how the obstacles can be solved. The element types which were considered were precast solid concrete slabs, solid concrete wall panels and concrete sandwich elements. The study was conducted as a qualitative study with five interviews with construction managers. The study concludes that there are numerous differences between using reused concrete elements and newly fabricated when it comes to lifting, connections and utility as well as electrical installations. The main differences for reused concrete elements when it comes to lifting are the lack of attachment for the lifting devices and uncertainties regarding the structural integrity during the lifting, which can be solved by using alternatives lifting methods and/or dividing the elements into smaller parts. When it comes to connections, the main differences are that reused concrete elements lack holes for connections, which can be solved by drilling new holes. Drilling new holes can also be made in order to fit utility and electrical installations in the reused concrete panels. However, drilling in concrete is expensive, time-consuming and demands measures to ensure a good work environment. Furthermore, the results show that prefabricated, and not in-situ cast concrete elements, should be chosen for reuse, which has also been found in previous studies. Another conclusion in this study is that a great obstacle for reusing concrete elements is that the load bearing capacity of the reused concrete elements is unknown, and praxis is missing for the elements when it comes to testing the load bearing capacity and classifying the elements. In conclusion, even if the issue regarding the load bearing capacity of the elements gets solved, other remain. These include increased construction time and costs, due to the differences in managing elements for lifting and connections, to preparing utility and electrical installations and for establishing the load bearing capacity of the reused elements.