Influencing Factors of Physical Properties of CO2 Mineralized Recycled Aggregate and Its Mechanism
YUAN Qiang
ZHANG Jiaoling
ZHANG Suhui
DING Rensheng
Abstract：The influencing factors affecting the water absorption and apparent density of recycled aggregate(RA)after CO2 mineralization were analyzed.Results show that the physical properties of RA improved significantly after CO2 mineralization.And as the carbon sequestration increases,the physical properties of RA improve more significantly.The strengthening effect of RA after carbonation is the best,when the water content of RA is 1.3％,the temperature and relative humidity of 50 ℃ and 98％,CO2 concentration of 99％,pressure of 0.15 MPa and carbonation time of 24 h.At these conditions,compared with untreated recycled aggregete,the CO2 uptake of recycled aggregate is 1.77％,the water absorption of RA is reduced by 33.47％,the apparent density of RA is increased by 2.06％.After CO2 mineralization,Ca(OH)2 and calcium silicate hydrated(C-S-H)gel converted to calcite in the pore makes the interface transition zone dense and the porosity decrease(from 22.07％to 12.78％),which realized the storage of CO2 by recycled aggregate and the physical properties of RA are improved.
Keywords：recycled aggregate(RA)CO2 mineralizationperformance improvementmicrostructural analysis
Publication Date：2024-10-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 895-903 )