增强粘土的强度通过在各种重塑水含量处的石灰砂稳定,提高粘土的强度
Shuai Qi1,2, Jinhui Liu1,2, Wei Ma1,2
1School of Civil and Transportation Engineering, Beijing University of Civil Engineering and Architecture, Beijing 102616, China.
Materials (Basel, Switzerland)
|July 30, 2025
概括
重塑的水含量显著影响了石灰砂稳定粘土的强度. 最佳的水含量 (w) 增强了土壤组织密度,而超过它会削弱结构,影响不受限制的压力强度 (UCS).
科学领域:
- 地质技术工程 地质技术工程
- 土壤稳定 土壤稳定
- 材料科学 是一种材料科学.
背景情况:
- 在石灰砂稳定粘土建筑中重塑水含量 (w) 会导致变性强度增强.
- 水含量对土壤结构和稳定土壤强度的影响仍未得到充分研究.
- 了解这些影响对于保持一致的次级性能至关重要.
研究的目的:
- 为了研究重塑水含量 (w) 对纯粘土和石灰砂稳定粘土的土壤结构和不受限制的压力强度 (UCS) 的影响.
- 为了确定土壤组织从密集到减弱的转变处的特征性水含量 (w_cha).
- 阐明强度增强和减弱背后的机制,与水含量和土壤成分相关.
主要方法:
- 在纯粘土和石灰砂稳定粘土样本上进行了不受限制的压缩试验.
- 微观观察被用来分析土壤结构的变化.
- 用4%的石灰和50%的沙子准备了样本.
主要成果:
- 重塑水含量 (w) 强烈影响土壤组织,减少基质吸收和聚合物形成,因为w从最佳的干燥到潮湿增加.
- 鉴定出一种特征性的水含量 (w_cha),标志着从土壤组织密度 (w ≤ w_cha) 过渡到结构性削弱 (w > w_cha).
- 不受限制的压力强度 (UCS) 呈现出一个钟形图案, w,在w_cha或附近达到峰值,在不同的水含量下观察到强度增强有效性的变化.
结论:
- 重塑水含量是控制土壤结构和石灰砂稳定粘土的UCS的关键因素.
- 添加沙子和石灰可以显著地提高UCS,因为由于改善土壤结构,水含量增加到w_cha.
- 超过 w_cha 会导致由于沙粒之间的聚合物分解和滑效应而降低UCS的有效性.
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