CONREPAD

With the rapid development of construction industry, construction and demolition wastes (C&DW) are largely generated yearly. Meanwhile, good quality natural aggregates are in shortage. Up to now, only a small proportion of C&DW is reused.

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omponents of C&DW typically include concrete, wood, metals, gypsum, asphalt, bricks and other materials. Old concrete is the most abundant material among various types of C&DW. The use of recycled concrete aggregates (RCA) crushed from old concrete to replace or partially replace the natural aggregates (NA) has become more common.

RCA are mainly composed of a mix of natural aggregates and hardened adherent cement paste. The latter is usually much more porous than natural aggregates and leads to a large water demand which makes RCA harder to recycle into concrete. Properties of RCA such as water absorption, porosity, and shape can deeply influence the properties of fresh concrete as well as mechanical properties and durability of concrete made with RCA. The packing density of the different composition can also deeply influence the properties of fresh concrete as well as mechanical properties and durability of concrete.

CONREPAD : Design of concrete with recycled concrete aggregates by means of Packing Density Method

The objective of this project is to develop a concrete with recycled aggregates by using the packing density method. This method can increase the strength of concrete by improving the packing density of aggregates. The aim is to formulate a concrete with type C35/45, which can be used in the development of pre-fabricated components used in civil engineering and construction industry.

Related publications

• Tentatives de prétraitement des granulats recyclés pour l’amélioration des bétons préfabriqués. Z. Zhao, L. Courard, S. Remond, D. Damidot, T. Fiandaca. 16e édition des Journées Scientifiques du Regroupement Francophone pour la Recherche et la Formation sur le Béton (RF)2B, EPFL, Lausanne, Swiss, 09-10 July 2015.
• Toward the quantification of the cement paste content of fine recycled concrete aggregates by salicylic acid dissolution corrected by a theoretical approach. Z. Zhao, D. Damidot, S. Remond, L. Courard. The 14th International Congress on the chemistry of Cement (ICCC2015-Beijing), Beijing, China, 13-16 October 2015.
• Une nouvelle méthode de caractérisation des granulats recyclés industriels: application aux mortiers. Z. Zhao, S. Remond, D. Damidot L. Courard. 2e édition de la Conférence Internationale Francophone: Nouveaux Matériaux et Durabilité (NoMaD), Douai, France, 5-6 November 2015.
• Influence de la fraction granulaire et de l'origine des granulats recyclés sur leurs propriétés. Z. Zhao, L. Courard, F. Michel, S. Remond, D. Damidot. 34èmes Rencontres Universitaires de Génie Civil de l'Association Universitaire de Génie Civil (AUGC), Liège, Belgique, 25-27 may 2016.
• Improving properties of recycled concrete aggregates by accelerated carbonation. Z. Zhao, S. Remond, D. Damidot. L. Courard, F. Michel. 4th international conference in Sustainable Construction Materials and Technologies (SCMT4), Las Vegas, USA, 7-11 August 2016.
• Mechanical and durability properties of concrete made with fine recycled concrete aggregates. Z. Zhao, L. Courard, F. Michel, S. Remond, D. Damidot. The 3rd International RILEM Conferences on Microstructure Related Durability of Cementitious Composites (Microdurability2016), Nanjing, China, 24-26 October 2016.