基于有效介质方程的混凝土氯离子扩散模型及扩散规律分析

沈才华; 陈伟; 陈晓峰; 谢飞; 吕世明; 许修亮

doi:10.13204/j.gyjzG20122608

基于有效介质方程的混凝土氯离子扩散模型及扩散规律分析

doi: 10.13204/j.gyjzG20122608

1. 河海大学岩土力学与堤坝工程教育部重点实验室, 南京 210098;
2. 浙江省交通规划设计研究院, 杭州 310012;
3. 保利长大海外工程有限公司, 广州 510623

基金项目:

国家自然科学基金重点项目（41830110）；浙江省交通运输厅科技计划项目（2016008）；保利集团科技项目（20198133316）。

详细信息

作者简介:
沈才华,男,1976年出生,博士,副研究员。电子信箱:shencaihua@163.com

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出版历程
- 收稿日期: 2020-12-26
- 网络出版日期: 2022-10-28

Chloride Diffusion Model and Diffusion Law Analysis of Concrete Based on GEM Equation

1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing 210098, China;
2. Zhejiang Provincial Institute of Communications Planning,Design & Research, Hangzhou 310012, China;
3. Poly Changda Overseas Engineering Co., Ltd., Guangzhou 510623, China

摘要

摘要: 氯离子在混凝土内的扩散预测是氯离子环境下混凝土耐久性预测的重点和难点。采用Nernst-Einstein方程改进有效介质（GEM）方程一般式，结合试验数据推导了可以预测不同空隙特征、不同保护层厚度混凝土的氯离子扩散过程方程，分析了混凝土养护龄期，矿物掺合料量，纤维掺加量对氯离子扩散过程方程中扩散指数n的影响规律，结合使用寿命预测模型，以氯离子浓度为控制目标，预测了100年设计寿命时，不同混凝土保护层厚度下的临界混凝土孔隙率要求，当最小保护层厚度为6 cm时，混凝土的孔隙率应控制在8%以下，预测结果基本合理，预测方法为沿海混凝土结构工程的氯离子腐蚀耐久性优化设计提供了参考。
- GEM方程 /
- 耐久性 /
- 氯离子 /
- 扩散指数
Abstract: The prediction of chloride diffusion in concrete is the key and difficult point of durability prediction of concrete in chloride environment. Nernst-Einstein equation was used to improve the general formula of GEM equation. Combined with test data, the chloride diffusion process equation of concrete with different void characteristics and different thicknesses of protective layer was derived. The influence of concrete curing age, mineral admixture and fiber content on the diffusion index n in the equation was analyzed. The life prediction model, with chloride ion concentration as the control target, predicted the critical porosity requirements of concrete under different concrete cover thicknesses with 100-year design life. When the minimum cover thickness was 6 cm, the concrete porosity should be controlled below 8%. The prediction results were basically reasonable. The prediction method could provide a reference for the optimal design of chloride corrosion durability of coastal concrete structures.
- GEM equation /
- durability /
- chloride ion /
- diffusion index

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参考文献(26)

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