纳米土壤改良技术，使用水泥。

Nano soil improvement technique using cement.

机构信息

Department of Civil Engineering, Faculty of Engineering, Buein Zahra Technical University (IKIU-BZ), Qazvin, Iran.

Department of Geotechnical and Hydraulic Engineering, Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Gdansk, Poland.

出版信息

Sci Rep. 2023 Jul 3;13(1):10724. doi: 10.1038/s41598-023-37918-z.

DOI:10.1038/s41598-023-37918-z

PMID:37400546

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10318072/

Abstract

Nano soil-improvement is an innovative idea in geotechnical engineering. Nanomaterials are among the newest additives that improve soil properties. Herein, laboratory tests, such as unconfined compressive strength, direct shear test, and initial tests, were conducted to investigate the geotechnical properties of Kelachay clay with micro- and nanosized cement to evaluate its particles in untreated soil and observe changes in the behavioral properties of treated soil compared to those of untreated soil. Scanning electron microscopy and X-ray fluorescence images were analyzed before and after the grinding process to determine the nature of the studied particles. Furthermore, effects of time and nanocement content (0%, 1%, 3%, 5%, and 7%) on curing performance were evaluated. The optimum percentage of nano-cement was found to be 7%, which increased the unconfined compressive strength by up to 29 times and reduced the strain at rupture by 74% compared to the untreated soil. The results showed that nano-cement significantly improved the strength and stiffness of the soil-cement mixture by forming calcium silicate hydrate (C-S-H) gel that filled the pores and bonded the soil particles. Nano-cement also acted as a nucleation site for more C-S-H growth, enhancing the durability and strength of the mixture.

摘要

纳米土壤改良是岩土工程中的一个创新理念。纳米材料是改善土壤性能的最新添加剂之一。本文通过无侧限抗压强度、直剪试验和初始试验等实验室测试，研究了用微纳米水泥改良克拉奇粘土的岩土特性，以评估其在未处理土壤中的颗粒，并观察处理土壤与未处理土壤相比行为特性的变化。在研磨前后分析了扫描电子显微镜和 X 射线荧光图像，以确定研究颗粒的性质。此外，还评估了时间和纳米水泥含量（0%、1%、3%、5%和 7%）对固化性能的影响。研究发现，纳米水泥的最佳含量为 7%，与未处理的土壤相比，纳米水泥可将无侧限抗压强度提高高达 29 倍，并将断裂应变降低 74%。结果表明，纳米水泥通过形成填充孔隙和粘结土壤颗粒的硅酸钙水合物（C-S-H）凝胶，显著提高了土壤-水泥混合物的强度和刚度。纳米水泥还可以作为更多 C-S-H 生长的成核点，增强混合物的耐久性和强度。