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Updated: Oct 2, 2025
06:27
Expression of Cementitious Pore Solution and the Analysis of Its Chemical Composition and Resistivity Using X-ray Fluorescence
Published on: September 23, 2018
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Macroscopic and Microscopic Properties of Cement Paste with Carbon Dioxide Curing
Jing Zhu1, Zijian Qu1, Siqi Liang1
1College of Civil Engineering and Architecture, Harbin University of Science and Technology, Harbin 150080, China.
Materials (Basel, Switzerland)
|February 25, 2022
Summary
Carbon dioxide curing accelerates cement setting and enhances mechanical strength. This method also improves cement paste compactness and reduces water absorption, offering a viable carbon capture strategy.
Area of Science:
- Materials Science
- Environmental Science
- Civil Engineering
Background:
- Greenhouse gases, primarily carbon dioxide (CO2), contribute to global warming.
- Utilizing CO2 in cement-based materials presents an effective carbon capture method.
Purpose of the Study:
- To investigate the effects of CO2 curing on cement paste properties.
- To explore the carbonation reaction mechanism using advanced analytical techniques.
Main Methods:
- CO2 curing was applied to cement pastes with water-cement ratios of 0.3, 0.4, and 0.5.
- Properties measured included setting time, electrical resistivity, dry shrinkage, water absorption, and mechanical strengths (flexural and compressive).
- Microscopic analysis utilized scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA).
Main Results:
- CO2 curing accelerated cement paste setting time.
- Electrical resistivity increased with CO2 curing but decreased with higher water-cement ratios.
- Mechanical strengths and dry shrinkage ratio increased with CO2 curing, while water absorption decreased.
- Microscopic analysis revealed accelerated cement reactions and improved cement paste compactness.
Conclusions:
- CO2 curing enhances cement paste mechanical properties and compactness.
- The study demonstrates a promising approach for CO2 utilization in construction materials.
- CO2 curing positively influences key performance indicators of cement-based materials.
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