为研究纳米MgO对滨海水泥土的改性效果,对纳米MgO改性水泥土(简称NmCS)进行了力学试验和微观测试。通过室内直接剪切试验,研究了纳米MgO的掺入比对水泥土力学特性的影响规律;利用扫描电镜的微观测试方法,观察不同纳米MgO掺入比的NmCS试样的微观结构,分析了纳米MgO改善水泥土强度的机理。结果表明:①纳米MgO改性水泥土强度存在最优掺入比,本次试验对应最优掺入比为10‰;②未掺入纳米MgO的滨海水泥土以小颗粒-松散结构为主,纳米MgO掺入比为10‰的NmCS微观结构最为致密,宏观表现为力学强度的提高。研究结果对现场使用纳米MgO改性水泥土的最优掺量提供试验参考。
张陈
,
李娜
,
王伟
,
袁俊平
,
姜屏
,
吴王意
,
傅克贤
. 纳米MgO改性滨海水泥土的直剪试验及微观机理[J]. 长江科学院院报, 2019
, 36(4)
: 135
-139
.
DOI: 10.11988/ckyyb.20180910
To investigate the effect of nano-MgO on cement-treated seashore soil, mechanical test and microscopic test were conducted on nano-MgO modified cement-treated seashore soil (NmCS). The mechanical performances of NmCS samples with varied cement content and nano-MgO content were examined via indoor direct shear test. Furthermore, the micro-structural characteristics and mechanism were studied by using SEM technology. Test result unveiled that: (1) there exists an optimum content of nano-MgO for NmCS. Specifically in the test of the present research, the optimum content of nano-MgO is 10‰. (2) Cement-treated seashore soil in the absence of nano-MgO is dominated by loose-structure and small particles; while NmCS with 10‰ nano-MgO is the most compact, reflected as in the improvement of mechanical strength.
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