Title:
Effect of Milling on the Reactivity of Mixed Recycled Aggregate Powder as an SCM
Author(s):
Jingwen Liu, Pieter Rauwoens, Özlem Cizer
Publication:
Symposium Paper
Volume:
362
Issue:
Appears on pages(s):
292-301
Keywords:
supplementary cementitious materials (SCMs), blended cement, construction and demolition waste (C&DW), mixed recycled aggregate, reactivity, cement hydration, R3 test
DOI:
10.14359/51740890
Date:
6/6/2024
Abstract:
Mixed recycled aggregate (MRA) powder derived from construction and demolition waste possess significant potential as an alternative supplementary cementitious material. Understanding and improving its reactivity is essential for facilitating its use in cementitious materials. This study investigates the effects of milling on MRA powder’s characteristics and reactivity. The milling parameters investigated are powder-to-balls mass ratio and milling duration. XRD analysis results indicate that pre-processing of milling induces a complete disorder of the clay mineral and partial amorphization of calcium carbonate and dolomite in MRA, resulting in a higher amorphous content. R3 heat release test indicates that the reactivity was substantially improved and can achieve the same level as pure red brick powder. Additionally, both lowering powder-to-balls mass ratio and prolonged milling duration effectively improve the milling efficiency. High powder content should be avoided owing to the likelihood of surface coating of milling balls with powder which would greatly reduce the energy transfer.