通过微生物诱导的酸盐沉 (MICP) 凝固的岩沙的机械性能
Gang Li1, Yi-Jia Zhang1, Xue-Qing Hua1
1Shaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi'an, 710123, Shaanxi, China.
Scientific reports
|September 30, 2024
概括
微生物诱导的石沉 (MICP) 有效地结合沙漠沙,控制沙漠化. 这种绿色方法提高了沙子的强度,降低了透性,为干旱环境提供了可持续的解决方案.
科学领域:
- 地质技术工程 地质技术工程
- 环境科学 环境科学
- 微生物学 微生物学
背景情况:
- 荒漠化和沙尘暴带来了重大的环境挑战.
- 控制荒漠化需要经济,绿色和持久的砂粘合方法.
- 微生物诱导的石沉 (MICP) 已成为一个有前途的技术.
研究的目的:
- 为了研究MICP的可行性,用于处理沙漠岩石沙子.
- 分析初始干密度,凝固数和固化时间对沙子特性的影响.
- 揭示MICP在岩沙中的凝固原理.
主要方法:
- 进行了透性测试和不受限制的压力强度 (UCS) 测试.
- 扫描电子显微镜 (SEM) 和X射线衍射 (XRD) 用于微观结构分析.
- 这项研究检查了具有低粘土含量,细颗粒和低水含量的岩砂.
主要成果:
- 增加了初始干密度和凝固数,降低了液压导电性,改善了UCS.
- 在最佳条件下 (1.65 g/cm3 干密度,20 个凝固数, 3 小时固化) 产生 0.00151 cm/s 导电率和 1050.30 kPa UCS.
- 在UCS和CaCO3含量之间发现了强烈的相关性 (R2=0.912),证实了MICP的强化作用.
结论:
- MICP是一种可行且有效的方法,用于凝固沙漠岩岩沙.
- 石灰岩沉增强了粒子间的摩擦,并通过填充孔隙来降低透性.
- 这项研究为管理沙漠沙漠地区提供了宝贵的见解.
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