用大麦灰和石灰稳定广土壤的工程性质:吉玛镇地下土壤的案例研究
Alemu Balcha1, Mohammed Hassen1, Anteneh Geremew1
1Faculty of Civil and Environmental Engineering, Jimma University, Jimma, Ethiopia.
Scientific reports
|November 21, 2025
概括
这项研究表明,将10%的石灰与10%的大麦灰 (BHA) 结合起来,有效地稳定了埃塞俄比亚广的土壤,用于道路建设. 这种可持续的混合物提高了土壤的强度,减少了膨胀,满足了更高的次级标准.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
背景情况:
- 膨胀的土壤在道路建设中存在重大挑战,因为它们的收缩膨胀特性.
- 传统的稳定剂,如水泥和石灰是有效的,但昂贵和环境问题.
- 需要可持续的,本地来源的替代品来稳定广的土壤.
研究的目的:
- 为了研究大麦灰 (BHA) 作为稳定广土壤的pozzolanic添加剂的有效性. 来自埃塞俄比亚的吉玛.
- 确定石灰和BHA的最佳混合物,以改善道路建设的土壤特性.
- 根据埃塞俄比亚道路管理局 (ERA) 的次级标准评估性能.
主要方法:
- 用不同百分比的石灰 (0-20%) 处理土壤样本以确定最佳含量.
- 然后将最佳的石灰含量与BHA (0-20%) 相继增加.
- 评估的属性包括可塑性指数 (PI),加州轴承比率 (CBR),不受限制的压力强度 (UCS) 和微结构分析 (SEM).
主要成果:
- 添加10%的石灰使PI降至22%,CBR增加至9.72%,符合S4次级标准.
- 10%的石灰和10%的BHA混合物进一步将PI降低到18%,并将CBR增加到18.42%,符合S5亚等级标准.
- SEM分析证实改善了土壤矩阵密度,减少了多孔性 (从17.33%降至6.74%),并增强了水泥粘合.
结论:
- 10%的石灰和10%的BHA的混合物是稳定广土壤的高效和可持续的解决方案.
- 这种方法为传统稳定剂提供了一种环保且具有成本效益的替代方案.
- 这些发现支持在基础设施开发中使用当地可用的农业副产品.
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