• Van De Wouw, Perry M. F.
• Brouwers, H. J. H.
• Florea, Miruna V. A.

Abstract

Worldwide, the removal of debris and reconstruction is requested when natural<br/>disasters and conflicts cause damaged or collapsed buildings. The on-site recycling of concrete waste into new structural concrete decreases transport and production energy costs, reduces the utilization of raw materials, and saves the use of limited landfill space. The application of recycled concrete aggregates (RCA) in structural concrete is currently limited, since concrete recycling involves application as road base material or in non-structural concrete with low strength requirements. Applying an optimised crushing method could improve the applicability of RCA in structural concrete. The quality of the initial concrete investigated is unknown, and embedded defects influence the quality of the final concrete made with RCA. Separating the hardened cement paste (HCP) from the aggregates through optimised crushing minimises the influence of the initial concrete on the quality of concrete made with RCA. In turn, the HCP can be extracted, reducing water absorption and minimising workability problems. Through this, optimised crushing makes the application of recycled concrete into new concrete far less troublesome, and therefore widely applicable and highly suitable for post disaster areas.<br/>This study primarily looks into the influence of the optimised crushing process on the resulting particles of the produced RCA. For this, concrete demolition waste is passed through the optimised crusher three times. An initial visual assessment of the RCA produced is made and the specific aggregated density measured shows promising results regarding aggregate quality.

Topics

• density
• impedance spectroscopy
• laser emission spectroscopy
• strength
• cement
• defect