矿渣水泥基复合材料在杂散电流作用下的抗软水溶蚀机理研究

硅酸盐通报 ›› 2024, Vol. 43 ›› Issue (1): 200-208.

矿渣水泥基复合材料在杂散电流作用下的抗软水溶蚀机理研究

韩瑜^{1, 2}, 赵方粒¹, 赵翊彤^{1, 3}, 王宝民¹

1.大连理工大学土木工程学院,大连 116024;
2.辽宁省建设科学研究院有限责任公司,沈阳 110005;
3.中国电建集团成都勘测设计研究院有限公司,成都 610072

收稿日期:2023-08-03 修订日期:2023-10-16 出版日期:2024-01-15 发布日期:2024-01-16
通信作者: 王宝民,博士,教授。E-mail:wangbm@dlut.edu.cn
作者简介:韩瑜(1987—),女,博士研究生,高级工程师。主要从事混凝土耐久性的研究。E-mail:hanyu2010@mail.dlut.edu.cn
基金资助:
辽宁省重点研发计划项目(2020JH2/10100016)

Soft Water Leaching Resistance Mechanism of Slag Cement Based Composites under Stray Current

HAN Yu^1,2, ZHAO Fangli¹, ZHAO Yitong^1,3, WANG Baomin¹

1. Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 116024, China;
2. Liaoning Building Science Research Institute, Shenyang 110005, China;
3. Power China Chengdu Engineering Co., Ltd., Chengdu 610072, China

Received:2023-08-03 Revised:2023-10-16 Online:2024-01-15 Published:2024-01-16

摘要/Abstract

摘要： 在轨道交通工程运营期间,复杂的服役环境导致混凝土结构耐久性下降。本文主要研究了在杂散电流与软水溶蚀耦合作用下,矿渣掺量、水胶比和杂散电流电压强度对矿渣水泥基复合材料微观结构的影响。结合X射线衍射、热重、扫描电子显微镜和压汞等方法,分析了矿渣水泥基复合材料经溶蚀90 d后的物相组成、Ca(OH)₂含量、微观形貌以及孔结构变化。研究结果表明:矿渣掺量越大,矿渣水泥基复合材料内部的Ca(OH)₂含量越少,材料的孔隙率越低,结构更均匀致密;随着杂散电流电压强度的增加,矿渣水泥基复合材料内部的Ca(OH)₂和AFt含量变少,且AFt和Ca(OH)₂等物相边界变得模糊不清;矿渣水泥基复合材料中C-(A)-S-H的含量略有增多,孔隙率略有下降;随着水胶比的增大,矿渣水泥基复合材料内部的Ca(OH)₂含量变少,剩余物相含量变少,微观结构变得松散多孔,孔径结构整体粗化,孔隙率增大。

关键词: 矿渣水泥基复合材料, 杂散电流, 软水溶蚀, 矿渣掺量, 水胶比, 微观结构

Abstract: During the usage of railway transport, the complex environment leads to the decrease of durability of concrete structure. The effects of slag content, water-binder ratio and stray current voltage intensity on the microstructure of slag cement based composites under the coupling effect of stray current and soft water leaching were studied. The phase composition, Ca(OH)₂ content, microstructure and pore structure of slag cement based composites after 90 d calcium leaching were analyzed by X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and mercury intrusion method. The results show that the larger the slag content, the less Ca(OH)₂ content in slag cement based composites, the lower the porosity, and the more uniform and dense the structure. With the increase of stray current voltage intensity, Ca(OH)₂ and AFt content in slag cement based composites decreases, and the phase boundaries of AFt and Ca(OH)₂ become blurred. C-(A)-S-H content in the material increases slightly, and the porosity decreases slightly. With the increase of water-binder ratio, Ca(OH)₂ content in the material decreases, the residual phase content decreases, the microstructure becomes loose and porous, the pore size structure coarsens as a whole, and the porosity increases.

Key words: slag cement based composite, stray current, soft water leaching, slag content, water-binder ratio, microstructure

中图分类号:

TU528

韩瑜, 赵方粒, 赵翊彤, 王宝民. 矿渣水泥基复合材料在杂散电流作用下的抗软水溶蚀机理研究[J]. 硅酸盐通报, 2024, 43(1): 200-208.

HAN Yu, ZHAO Fangli, ZHAO Yitong, WANG Baomin. Soft Water Leaching Resistance Mechanism of Slag Cement Based Composites under Stray Current[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2024, 43(1): 200-208.

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