文献类型：期刊文献

中文题名：碱液(NaOH)对风积砂强度的影响与微观作用机理研究

英文题名：Effect of Alkali Liquid(NaOH)on the Aeolian Sand Strength and Its Microscopic Mechanism

作者：张重重 张宁 陈筠 陈泰徐 常强

第一作者：张重重

机构：[1]贵州大学资源与环境工程学院,贵阳550025;[2]中国电建集团贵阳勘测设计研究院,贵阳550081;[3]贵州理工学院继续教育学院,贵阳550003

第一机构：贵州大学资源与环境工程学院,贵阳550025

年份：2024

卷号：38

期号：3

起止页码：479-484

中文期刊名：土工基础

外文期刊名：Soil Engineering and Foundation

基金：国家自然科学基金项目(52104080);贵州省地质灾害监测预警与决策支持平台建设(Z113278)。

语种：中文

中文关键词：风积砂;NaOH;直剪试验;微观结构;SEM

外文关键词：Aeolian Sand;NaOH;Direct Shear Test;Microstructure;SEM

摘要：针对工程中风积砂强度不足的问题,利用碱液(NaOH)对风积砂进行处理。为验证风积砂强度是否改变,采用直剪试验进行判断,并找到较为合适的碱液浓度。为研究碱液对风积砂强化的微观作用机理,采用电镜扫描观测风积砂微观结构,并利用IPP(Image-Pro Plus)图像分析软件与PCAS软件对风积砂微观图像进行处理,提取微观参数。结果表明:(1)碱液的加入可以显著的提高风积砂的强度,但额外补充的Ca2+不会使土体强度得到更为有效的提升;(2)碱液浓度的提高会使土体的抗剪强度提升,但存在最优含量区间,过高的碱液浓度不会使抗剪强度得到更为明显的提升;(3)碱液加固后风积砂强度的变化与孔隙微观结构的变化之间存在一定关系;(4)微观作用机理上,NaOH与土体发生作用,产生片状聚合物去填充土体孔隙,并附着在颗粒表面,包裹土体颗粒,使土体强度得到提高。
In response to the problem of the insufficient strength of the aeolian sand in engineering,an alkaline solution(NaOH)is used to treat the aeolian sand.To verify whether the strength of the aeolian sand has changed,a direct shear test is used to determine the appropriate alkali concentration.To study the micro mechanism of the alkali solution in strengthening the aeolian sand,the microstructure of the aeolian sand was observed by using the electron microscopy scanning.The micro images of the aeolian sand were processed by using the IPP(Image Pro Plus)image analysis software and the PCAS software to extract micro parameters.The results indicate that:(1)the addition of the alkaline solution can significantly improve the strength of the aeolian sand,but the additional addition of Ca?+will not result in a more effective improvement in the soil strength;(2)An increase in the alkali concentration will enhance the shear strength of the soil,but there is an optimal content range.Excessive alkali concentration will not significantly improve the shear strength;(3)There is a certain relationship between the changes in the strength of the aeolian sand after the alkali solution reinforcement and the changes in the pore microstructure;(4)In terms of the microscopic mechanism,the NaOH interacts with the soil to produce the sheet-like polymers to fll soil pores and adhere to the surface of particles,enveloping soil particles,and improving the soil strength.