水泥-水玻璃改良粉质黏土渗透性能与微观机理研究  

Study on Permeability and Microscopic Mechanism of Cement-Water Glass Improved Silty Clay

作　　者：胡扬扬 刘银芳 苏德垠 郭易盟 朱碧堂 胡椿华 Hu Yangyang;Liu Yinfang;Su Deyin;Guo Yimeng;Zhu Bitang;Hu Chunhua(Jiangxi Key Laboratory of Geotechnical Infrastructure Safety and Control,East China Jiaotong University,Nanchang 330013,China;Fujian Geotechnical Engineering Investigation and Research Institute Co.,LTD.,Fuzhou 350001,China)

机构地区：[1]华东交通大学江西省地下空间技术开发工程研究中心,江西南昌330013 [2]福建岩土工程勘察研究院有限公司,福建福州350001

出　　处：《华东交通大学学报》2023年第6期32-38,共7页Journal of East China Jiaotong University

基　　金：国家自然科学基金面上项目(4197229);国家自然科学基金委重点国际合作研究项目(5202010500)。

摘　　要：针对南昌典型粉质黏土,制备了不同水泥及水玻璃掺量配比下的改良粉质黏土,通过对试样开展室内渗透试验、扫描电镜(SEM)与X射线衍射(XRD)测试,着重探讨了水泥掺量、水玻璃掺量、养护龄期对粉质黏土抗渗性能的影响规律。结果表明:改良粉质黏土的渗透系数在养护龄期7~14 d下降速度3倍高于14~28 d;随着水泥掺量的不断增加,改良粉质黏土的渗透系数不断下降且下降速率逐步变小;水玻璃掺量的增加可明显减小改良粉质黏土的渗透系数;水泥-水玻璃可协同作用提高粉质黏土的抗渗性,且掺量配比存在最优值24%水泥+6%水玻璃;相较于单掺水泥改良粉质黏土,水玻璃的掺入并未改变水化产物主要物相组成,而是促进水化反应进行,提高了C-S-H凝胶和C-A-S-H钙钒石等水化产物产量,大大减少了土颗粒间的孔、裂隙数量。In this paper,the effects of cement content,water glass content and curing age on the impermeability performance of silty clay were discussed by indoor penetration test,scanning electron microscopy(SEM)and X-ray diffraction(XRD)test on the typical silty clay in Nanchang.The results showed that the permeability coefficient of improved silty clay decreased at a rate of 3 orders of magnitude higher than that of 14~28 d at a curing age of 7~14 d.With the continuous increase of cement content,the permeability coefficient of improved silty clay decreased and the decline rate gradually decreased.The increase of water glass content can significantly reduce the permeability coefficient of improved silty clay.Cement-water glass can synergistically improve the impermeability of silty clay,and the optimal ratio of 24%cement+6%water glass has an optimal dosage.Compared with the improved silty clay with single cement,the incorporation of water glass does not change the main phase composition of the hydration product,but promotes the hydration reaction,and increases the yield of hydration products such as C-S-H gel and C-A-S-H calcium vanadite,and greatly reduced the number of pores and frac tures between soil particles.

关 键 词：粉质黏土 水泥-水玻璃 微观机理 渗透 

分 类 号：TU58[建筑科学—建筑技术科学] U25[交通运输工程—道路与铁道工程]