活性疏沉积基流化固化土壤:早期工程性能和微观结构机制
Qunchao Ma1, Kangyu Wang2, Qiang Li3
1School of Civil Engineering, Zhejiang University of Technology, Hangzhou 310015, China.
Materials (Basel, Switzerland)
|July 30, 2025
概括
这项研究通过添加二氧化烟雾 (SF) 来优化流化固化土壤 (FSS) 用于海洋堆清理修复. 8%的SF添加与0.525的水固体比 (WSR) 平衡可加工性和早期强度,以有效的整治.
科学领域:
- 地质技术工程 地质技术工程
- 海洋土木工程 海洋土木工程
- 材料科学 材料科学 材料科学
背景情况:
- 液化固化土壤 (FSS) 显示出对海洋堆清理的承诺.
- 目前的局限性包括狭窄的施工窗口和在固化之前易受侵蚀的影响.
研究的目的:
- 系统地评估FSS配方,使用疏沉积物,可变的烟 (SF) 含量 (0-12%) 和生激活.
- 为了确定最佳的混合设计,平衡流动性和早期机械性能,用于海上堆清理器的维修.
主要方法:
- 实验评估包括流动性,不受限制的压力强度 (UCS) 和直接剪切测试.
- 微结构分析利用X射线衍射 (XRD) 和扫描电子显微镜 (SEM).
- 评估了三种水固体比率 (WSR:0.525,0.55,0.575) 和四种SF替代水平 (0%,4%,8%,12%).
主要成果:
- 烟 (SF) 替代通过减轻流动性损失延长了运行期.
- 在8%的SF替代和WSR=0.55时观察到最佳性能,在3天的UCS中增加了22.78%,并在7天后改善了凝聚力和摩擦角度.
- 微结构分析证实了SF的pozzolanic反应产生C-S-H凝,但超过8%的水平导致未反应的颗粒破坏了矩阵.
结论:
- 8%的SF替代和0.525的WSR代表了用于海洋堆清理器维修的最佳组合.
- 实现流动性和早期强度之间的平衡对于稳定的FSS整治至关重要.
- 这些发现为开发持久有效的海洋基础设施维修解决方案提供了关键的见解.
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