Design and Research on the Preparation of Pervious Concrete Using Carbonized Steel Slag as a Full Component
To address the environmental pressures and resource waste caused by massive stockpiling of steel slag, this study developed a carbonated steel slag pervious concrete binder using 40% steel slag powder as the primary cementitious component combined with CaO and MgO. The mechanical performance evoluti...
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| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-05-01
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| Series: | Buildings |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-5309/15/9/1526 |
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| Summary: | To address the environmental pressures and resource waste caused by massive stockpiling of steel slag, this study developed a carbonated steel slag pervious concrete binder using 40% steel slag powder as the primary cementitious component combined with CaO and MgO. The mechanical performance evolution was investigated, while XRD, SEM, and TG-DTG microcharacterization techniques were employed to reveal the carbonation mechanism and strength formation principles. The results demonstrate that when CaO and MgO contents reached 5% and 15%, respectively, the 28d compressive strength of mortar increased by 134.49% compared to the reference group. Microstructural analysis confirmed that CaO reacted to form CaCO<sub>3</sub> crystals, while MgO enhanced strength by regulating CaCO<sub>3</sub> crystal morphology to optimize product structure. Using steel slag as an aggregate, carbonated steel slag pervious concrete was prepared to investigate the influence mechanisms of B/A ratio and W/B ratio on compressive strength, permeability coefficient, and carbonation effects. The post-carbonation strength increase was adopted to evaluate carbonation efficiency. Increasing B/A ratio enhanced paste filling in aggregate voids, raising 28d compressive strength to 24.76 MPa, but thickened paste coating layers reduced permeability coefficient to 0.33 mm/s while impeding CO<sub>2</sub> diffusion, decreasing carbonation strength growth rate by 22.76%. Initial W/B ratio elevation improved workability to increase strength to 23.76 MPa, whereas excessive water caused paste sedimentation and strength reduction. As W/B ratio rose, permeability coefficient decreased by 65.6%, while carbonation strength growth rate increased. The carbonated steel slag pervious concrete contained approximately 82% steel slag, demonstrating high resource utilization efficiency of steel slag and significant potential for carbon emission reduction. |
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| ISSN: | 2075-5309 |