Mechanism Analysis on Carbonation of Hardened Cement Paste with XCTSource: Journal of Materials in Civil Engineering:;2023:;Volume ( 035 ):;issue: 009::page 04023323-1Author:Yaocheng Wang
,
Fuzi Chen
,
Zhouyi Li
,
Wengen Yang
,
Baojian Zhan
,
Dawang Li
,
Feng Xing
,
Weiwen Li
DOI: 10.1061/JMCEE7.MTENG-15343Publisher: ASCE
Abstract: X-ray computed tomography (XCT) was used to monitor microstructure changes of hardened cement paste, with different water/cement ratios during a one-dimensional carbonation process. After removing equipment-induced measurement errors by a volume-constant method, the pores, dense hydration products, loose hydration products, and unhydrated cement in the sample were classified. Consequently, variation of each component with depth and carbonation duration were obtained, based on which mechanism of carbonation on hardened cement paste was conducted. Results showed that microstructure changes in hardened cement paste under CO2 effects is a coexisting simultaneous densification and cracking process. Within the entire carbonation process, the changes exhibited a general alternate pattern of densification–cracking–redensification, leading to connection of micropores into macro ones in hardened cement paste (i.e., the so-called carbonation-induced cracking); entire volume of the pores bigger than 4.4 μm did not present obvious changes during carbonation; a CO2 influence depth can be obtained by this method, which has an approximate linear relationship with the square root of carbonation duration and has limited influence with the water/cement ratio used in this study.
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contributor author | Yaocheng Wang | |
contributor author | Fuzi Chen | |
contributor author | Zhouyi Li | |
contributor author | Wengen Yang | |
contributor author | Baojian Zhan | |
contributor author | Dawang Li | |
contributor author | Feng Xing | |
contributor author | Weiwen Li | |
date accessioned | 2023-11-27T23:44:56Z | |
date available | 2023-11-27T23:44:56Z | |
date issued | 7/4/2023 12:00:00 AM | |
date issued | 2023-07-04 | |
identifier other | JMCEE7.MTENG-15343.pdf | |
identifier uri | http://yetl.yabesh.ir/yetl1/handle/yetl/4293810 | |
description abstract | X-ray computed tomography (XCT) was used to monitor microstructure changes of hardened cement paste, with different water/cement ratios during a one-dimensional carbonation process. After removing equipment-induced measurement errors by a volume-constant method, the pores, dense hydration products, loose hydration products, and unhydrated cement in the sample were classified. Consequently, variation of each component with depth and carbonation duration were obtained, based on which mechanism of carbonation on hardened cement paste was conducted. Results showed that microstructure changes in hardened cement paste under CO2 effects is a coexisting simultaneous densification and cracking process. Within the entire carbonation process, the changes exhibited a general alternate pattern of densification–cracking–redensification, leading to connection of micropores into macro ones in hardened cement paste (i.e., the so-called carbonation-induced cracking); entire volume of the pores bigger than 4.4 μm did not present obvious changes during carbonation; a CO2 influence depth can be obtained by this method, which has an approximate linear relationship with the square root of carbonation duration and has limited influence with the water/cement ratio used in this study. | |
publisher | ASCE | |
title | Mechanism Analysis on Carbonation of Hardened Cement Paste with XCT | |
type | Journal Article | |
journal volume | 35 | |
journal issue | 9 | |
journal title | Journal of Materials in Civil Engineering | |
identifier doi | 10.1061/JMCEE7.MTENG-15343 | |
journal fristpage | 04023323-1 | |
journal lastpage | 04023323-10 | |
page | 10 | |
tree | Journal of Materials in Civil Engineering:;2023:;Volume ( 035 ):;issue: 009 | |
contenttype | Fulltext |