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セメント改質後の細粒尾鉱の機械的特性に関する実験的調査
Yichen Wu1, Guangjin Wang1,2, Bing Zhao1
1School of Land and Resources Engineering, Kunming University of Science and Technology, Kunming 650093, China.
Materials (Basel, Switzerland)
|December 11, 2025
まとめ
本研究は、セメント処理された細粒尾鉱が建設材料として効果的に利用できることを明らかにしています。それらの機械的強度に影響を与える主な要因は、セメント砂比、養生期間、および浸漬時間です。
科学分野:
- 地盤工学
- 材料科学
- 廃棄物管理
背景:
- 細粒尾鉱は、粒子径が小さく、圧密が遅いため、利用が困難です。
- 効果的な利用には、安定化された場合の機械的特性の理解が必要です。
研究 の 目的:
- セメント処理された細粒尾鉱の機械的特性を調査すること。
- 混合比率と条件が強度に与える影響を決定すること。
- セメント処理された尾鉱の予測モデルを開発すること。
主な方法:
- 粒子径の95%が74μm未満のセメント処理尾鉱を調製しました。
- 36回の曲げおよび一軸圧縮試験を実施しました。
- XRD、SEM、範囲分析、ANOVA、および回帰分析により強度発達を分析しました。
主要な成果:
- 曲げ強度:0.43–2.07 MPa; 圧縮強度:3.02–12.52 MPa。
- 強度とセメント砂比(A)および養生期間(B)は正の相関があり、浸漬時間(C)とは負の相関がありました。
- 微細構造解析により、C-S-Hゲルとゼオライト様相が構造の一体性に寄与していることが明らかになりました。要因の重要度:A > B > C。
結論:
- セメント処理された細粒尾鉱は、顕著な機械的強度を示します。
- 予測モデルが開発され、検証されました。
- 結果は、尾鉱の持続可能な利用を固形廃棄物材料として支持しています。
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