Use of grinded hardened cement pastes as mineral addition for mortars

Recycled Concrete Aggregates (RCA) are not enough used in the construction sector due to their high porosity and water absorption capacity. Fine particles which composed of large amounts attached hardened cement paste even more difficult valorize, while they could be as mineral admixture mortar or concrete. The objective this work is find a recovery track for material addition. use porous powder cementitious mortars raises question effective definition such systems. Two powders used, first one grinded (porous), second limestone filler (non-porous). A comparison hydration degree, porosity, fresh, behaviors between pastes manufactured with two carried out. results show that has an impact on properties materials. Depending studied (fresh properties), substitution by done with, without taking into account absorption. Taking allows maintaining fluidity mixture but decreases significantly compressive strength replacement percentages larger than 20%.