What is the influence of old iron on reinforcing steel quality?

In collaboration with Leiden University and the University of Tokyo, Betonstaal.nl and Betonijzer Buig Centrale are participating in an international study on the influence of recycled material on the quality of reinforcing steel.

Concrete steel is primarily produced from scrap metals from, for instance, old cars, fences, and refrigerators. During the sorting process, deviant types of metal (various types of stainless steel, aluminum) are separated as much as possible. However, not all these materials can be sorted out. A part of them is processed during the production of reinforcing steel, which leads to mixing of different elements.

Do these materials affect the mechanical properties of reinforcing steel?

That is what the researchers are addressing in this study. Recycling processes from different countries are being examined. The difference in recycling between developed and less developed countries is evident. In less developed countries, sorting is done more cleanly (manually instead of mechanically), resulting in fewer deviant types of metals ending up in the reinforcing steel production process.

The expectation is that the research will be completed in March 2018. Afterwards, the research will be published in various scientific journals.