| 摘要: |
| 基于Fick第一定律和质量守恒定律，在水的质量守恒方程中考虑对流作用引起的水的改变量，建立了扩散和对流完全耦合的非饱和状态混凝土中的氯离子传输理论模型；采用交替方向隐式有限差分法（ADI）对传输控制方程进行数值求解，与Ababneh等提出的氯离子传输理论模型以及美国道路与运输协会的试验数据进行了对比.另外，基于物质守恒定律，通过定义容量矩阵、传递矩阵和氯离子通过率向量，并与瞬态热平衡方程中的各参量进行等效，给出了基于ANSYS热分析模块模拟非饱和状态混凝土中氯离子传输的数值方法.结果表明，所提出的非饱和状态混凝土中氯离子传输理论模型与美国道路与运输协会的试验数据之间的吻合程度要比Ababneh模型更好，但2种传输理论模型与试验数据之间的差距都非常小.因此，考虑对流作用引起的水的改变量对于实际工程不会起到太大影响，但能更好地与氯离子传输的物理过程相吻合，有助于完善非饱和状态混凝土中氯离子传输的理论体系.基于ANSYS的非饱和状态混凝土中氯离子传输模拟方法的精度不如氯离子传输理论模型高，但计算代价较小，适用于实际工程. |
| 关键词: 非饱和混凝土 氯离子传输 数值模拟 |
| DOI：103969/j.issn1007 9629201601008 |
| 分类号: |
| 基金项目:国家重点基础研究发展计划（973计划）项目（2011CB013600）；国家自然科学基金资助项目（51308166）；山东省自然科学基金资助项目（ZR2011EEQ028） |
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| Transport Mechanism of Chloride in Nonsaturated Concrete |
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JIA Lizhe, ZHANG Yingzi, WANG Kaiyuan, XU Tianxin, DUAN Yiming
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School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China
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| Abstract: |
| Considering the change of water mass by convection in water mass conservation equation, a new chloride transport model was developed based on Ficks first law and mass conservation law. The solution of this new chloride transport equation was derived by alternating direction implicit (ADI) finite difference method and the results are compared with chloride transport model by Ababneh and experimental data of American Association of Roads and Transport. Capacity matrix, transfer matrix and chloride passing rate vector are associated with variables in transient heat balance equation, a numerical simulation method by ANSYS thermal analysis module for chloride transport in nonsaturated concrete is derived based on mass conservation law, and the results are compared with the new chloride transport model and experimental data. The results indicate that the new chloride transport model is more consistent with experimental data of American Association of Roads and Transport than Ababneh model. The difference of different models is very small, and considering the change of water mass by convection gives a little influence on practical engineering. The model of considering the change of water mass by convection is more consistent with chloride transport process in nonsaturated concrete, and can improve the theoretical system of chloride transport in nonsaturated concrete. The numerical simulation method based on ANSYS is less accuracy than the theoretical model but its more convenient for application in engineering practice. |
| Key words: nonsaturated concrete chloride transport numerical simulation |
