通过酸溶液沉到水泥溶液中对石灰砂进行生物增强的实验研究
Zhao Jiang1, Renjie Wei1, Di Dai1
1Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing 210098, China.
Materials (Basel, Switzerland)
|October 14, 2023
概括
将盐酸 (HCl) 添加到微生物诱导的碳酸沉 (MICP) 中,可以显著提高土壤强度. 这种优化的方法增强了石灰砂的固化和无限制的压力强度 (UCS),用于实际的工程应用.
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:
- 微生物诱导碳酸盐沉 (MICP) 是改善土壤性能,如强度和稳定性的有希望的技术.
- 当前MICP方法的一个主要限制是它们的低固化效率,阻碍了实际应用.
- 石灰砂土壤由于其成分,对凝固具有独特的挑战.
研究的目的:
- 优化MICP处理方案,以提高固化速度和有效性.
- 为了研究在盐酸 (HCl) 溶液中配制凝固溶液的影响.
- 评估经过处理的石灰岩砂的机械性能的改善,特别是不受限制的压力强度 (UCS).
主要方法:
- 在0.2M HCl溶液中配制1M凝固溶液,用于MICP反应.
- 在五个处理周期中用优化的溶液处理石灰砂柱.
- 测量处理过的沙柱的未受限制的压力强度 (UCS),并与对照组进行比较.
主要成果:
- 用HCl增强的MICP处理产生了1312.6kPa的不受限制的压力强度 (UCS).
- 与传统治疗组相比,UCS的增加约为1357%.
- 分析证实,HCl从石灰砂中溶解的金属离子在增强UCS方面发挥着至关重要的作用.
结论:
- 在HCl中配制MICP水泥溶液显著加快了固化速度,并提高了石灰砂土的强度.
- 溶解金属离子的存在被确定为HCl辅助MICP增强性能的一个关键因素.
- 这种优化的方法在现实工程项目中为MICP水泥化石灰砂提供了可行的策略.
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