Toward a complete reemployment of aggregates from demolition work in situ

Abstract

The recycled concrete aggregates (RCA) produced by the demolition of old buildings seem to be an option in order to construct new buildings and to preserve the environment by the reusing of inert materials, reducing the resort to the natural materials and the disposal in landfills. Numerous countries are multiplying studies concerning this subject and evolving their regulations consequently. These days, it seems fundamental to go further in the environmental protection by minimizing the impact of road transport through the implementation, on the same urban site, of the following process: in a first phase the demolition, then recycling, then storing and finally reconstructing the buildings. In fact, the increase of the recovery rates of recycled concrete aggregates seems globally meeting the current environmental constraints. However, the transportation of the demolition wastes from the site to the recycling plant and potentially their return are still problems, which are not correctly considered in environmental assessments. Research of the briefest possible short loop is not really developing in France. This study is devoted to understanding the stumbling blocks to this development. If the aim of the financial viability of the short loop is obvious, the study shows that the complexity of project building in urban refurbishment is the first block to remove. The role of the various operators of the project doesn’t comply with the global coherence provided by short loop circuits. The study highlights several technical blocks concerning the recycling organization in situ, the storing of recycled concrete aggregates and finally their reuse in order to produce new concretes.