The Effect of Grinding Process on Recycled Cement Paste Fines

Abstract

In many countries, major portions of construction and demolition waste (C&DW) consists of concrete waste [1]. The uses of recycled aggregate from concrete waste include both base/sub-base infrastructure and structural applications. Each application requires a different quality and therefore, a different treatment. When concrete waste is crushed, a certain amount of paste/mortar from the original cement mortar remains attached to the aggregate particles, which forms a weak, porous and cracky layer [2]. The use of recycled aggregate in new concrete requires a beneficiation process, which separates the natural aggregate from the attached cement paste/mortar. The clean natural aggregate is used as recycled aggregate, while the attached cement paste/mortar is of no use. As a result, the majority of concrete recycling studies focus on the recycled aggregate only, clean from the attached cement paste/mortar. This work focuses on the old cement paste/mortar itself.