{"title":"Analysis of time-resolved water distribution and paramagnetic contents migration during alkali-activation process of Metakaolin using PD-MRI","authors":"Zian Tang , Yuanrui Song , Wenyu Li","doi":"10.1016/j.cemconres.2025.107871","DOIUrl":null,"url":null,"abstract":"<div><div>The alkali-activation process is known to be rapid and thus challenging to characterize. In this work, we used proton density magnetic resonance imaging (PD-MRI) to observe the water distribution during the alkali-activation process of metakaolin. With the obtained visible brightness changing of the solid phase and the bled water, the setting time of the alkali-activated materials (AAMs) can be determined, while the migration of paramagnetic contents (Fe) and the accumulation of unreacted base can be traced. Moreover, the total shrinkage of the activated paste was calculated for the first time based on MRI in this manuscript. The results show the potential use of this technique for characterizing AAMs with lower paramagnetic content.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":"193 ","pages":"Article 107871"},"PeriodicalIF":10.9000,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cement and Concrete Research","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0008884625000900","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
The alkali-activation process is known to be rapid and thus challenging to characterize. In this work, we used proton density magnetic resonance imaging (PD-MRI) to observe the water distribution during the alkali-activation process of metakaolin. With the obtained visible brightness changing of the solid phase and the bled water, the setting time of the alkali-activated materials (AAMs) can be determined, while the migration of paramagnetic contents (Fe) and the accumulation of unreacted base can be traced. Moreover, the total shrinkage of the activated paste was calculated for the first time based on MRI in this manuscript. The results show the potential use of this technique for characterizing AAMs with lower paramagnetic content.
期刊介绍:
Cement and Concrete Research is dedicated to publishing top-notch research on the materials science and engineering of cement, cement composites, mortars, concrete, and related materials incorporating cement or other mineral binders. The journal prioritizes reporting significant findings in research on the properties and performance of cementitious materials. It also covers novel experimental techniques, the latest analytical and modeling methods, examination and diagnosis of actual cement and concrete structures, and the exploration of potential improvements in materials.