The Effect of Specific Surface Area of Silicomanganese Slag as Cement Replacement on Properties of Concrete
| dc.contributor.author | Li Feng | |
| dc.date.accessioned | 2026-05-19T02:49:05Z | |
| dc.date.issued | 2026 | |
| dc.description | Silicomanganese slag (SiMnS), an electrolytic manganese byproduct, poses environmental risks through unsustainable storage/landfilling, leaching pollutants (e.g., heavy metals) into ecosystems, but pretreatment (drying/grinding) unlocks its pozzolanic potential for cement substitution in concrete, offering dual waste valorization and resource conservation. At present, most of the research on SiMnS concrete at home and abroad is limited to the influence of SiMnS content on concrete performance, and there is very little research on the effect of SiMnS specific surface area (SSA) on workability, mechanical properties, and durability of concrete. This study investigated the effects of the SSA of SiMnS on concrete properties. Employing a controlled variable approach, the experimental design sets SSA levels of 60 m²/kg, 120 m²/kg, 235 m²/kg, and 400 m²/kg with cement replacement ratios from 0% to 40%wt. Concrete specimens are prepared under standard curing conditions. Performance tests include slump measurement, compressive/flexural strength evaluation, freeze-thaw resistance, chloride ion penetration resistance, and sulfate attack resistance. Data analysis integrates the AHP-entropy method with statistical techniques to assess indicator weights. Results indicate that SiMnS with an SSA of 235 m²/kg, when used to replace 10%wt of the cement, provides optimal performance in concrete. Concrete with this combination demonstrated enhanced compressive strength, improved resistance to freeze-thaw cycles, and higher sulphate and chloride ion penetration resistance compared to other configurations. The experimental data were statistically evaluated using a combination of the analytic hierarchy process (AHP) and the entropy weight method, referred to as the AHP-entropy method. Based on the comprehensive ranking of SiMnS SSA schemes, the optimal scheme (SSA = 235 m²/kg, dosage = 10%wt) was identified, which aligns with the experimental conclusions, thereby validating the experimental results. When the SiMnS content exceeded iv 10%wt, or SSA surpassed 400 m²/kg, the compressive strength and durability decreased, indicating that excessive fineness or slag content could undermine the comprehensive properties of concrete. The findings show that the larger SSA of SiMnS enhances pozzolanic reactivity while appropriate SiMnS content balances strength and durability. However, excessive SiMnS content or a smaller SSA leads to reduced performance due to lower hydration efficiency and structural instability. This study demonstrates that SiMnS with a SSA of 235 m²/kg and 10% cement replacement optimally balances workability, mechanical strength (1.79% and 2.87% improvements in compressive and flexural strength, respectively), and durability (25% higher chloride resistance, 10.1% improved sulfate resistance). While higher SSA enhances pozzolanic reactivity, excessive replacement (>10%) or SSA (>400 m²/kg) reduces performance due to hydration inefficiency and microstructural instability. The AHP-entropy method validates this synergy, providing a data-driven framework to industrialize SiMnS utilization—reducing CO₂ emissions and landfill waste while advancing circular economy goals in construction. Future work should optimize SSA via grinding or admixtures and assess long-term environmental impacts, particularly the leaching effects of heavy metals. | |
| dc.identifier.uri | https://scholarhub.unimas.my/handle/123456789/767 | |
| dc.language.iso | English | |
| dc.publisher | Universiti Malaysia Sarawak | |
| dc.relation.ispartofseries | Faculty of Engineering | |
| dc.subject | Cement—Research, Slag | |
| dc.title | The Effect of Specific Surface Area of Silicomanganese Slag as Cement Replacement on Properties of Concrete | |
| dc.type | PhD |