Effect of Temperature and Relative Humidity on Performance of CO2 Curing Steel Slag Products
LI Shanwu
FAN Zhanlin
LIU Jianhui
CHEN Zheng
SHI Caijun
Abstract：The response surface methodology(RSM)was employed to investigate the effects of temperature and relative humidity on the performance of steel slag products under CO2 curing(hereafter referred to as steel slag products).The results show that the interplay between temperature and relative humidity variably influences the carbonation process at different stages.During the initial stage of carbonation,CO2 diffusion emerges as a pivotal factor,albeit with incomplete carbonation.In the later stages,compressive strength and carbonation degree are predominantly affected by the solubility of Ca2+and CO2.Notably,when relative humidity falls below 30％,despite rapid CO2 diffusion,the low solubility hampers the reaction between CO32-and Ca2+,preventing the attainment of desired strength and carbonation levels.Increasing the temperature and relative humidity to 70 ℃ and 64％,respectively,the formation of nanoscale calcium carbonate is fostered,significantly reducing pore size and volume in steel slag by filling voids ranging from 40 nm to 180 nm,thereby enhancing material properties.
Keywords：steel slagCO2 curingtemperaturerelative humidityresponse surface methodology(RSM)
Publication Date：2025-01-27
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 33-41 )