中南大学学报（自然科学版）2024，Vol.55Issue(3)：1035-1045,11.DOI:10.11817/j.issn.1672-7207.2024.03.017
考虑非饱和效应的跨海隧道衬砌混凝土氯离子非线性对流-扩散侵蚀模型及其求解方法
A non-linear chloride convection-diffusion model and solution method for undersea tunnel lining concrete considering unsaturated effect
摘要
Abstract
To accurately predict chloride ion content within the lining of a subsea tunnel,a non-linear convection-diffusion erosion model for the unsaturated effect in the concrete lining of the subsea tunnel was proposed.Firstly,the influences of chloride ion binding effects,unsaturated diffusion within the concrete and unsaturated moisture infiltration on chloride ion transport were sequentially considered by introducing Langmuir isotherm adsorption,a power-law unsaturated diffusion equation and the VG-Mualem moisture transport model,which enabled the development of a theoretical model for chloride ion erosion in the unsaturated state of tunnel lining concrete.Secondly,a numerical solution method for the model was proposed based on the finite difference principle,and the effectiveness of the solution method was also validated.Finally,the reliability of the model was analyzed through experimental comparisons,and discussions on parameter analysis were conducted.The results show that water infiltration under unsaturated conditions has a dual promoting effect on ion transport in concrete,which gradually increases the saturation,diffusion coefficient,and permeability coefficient of concrete over time.At the early stage of external water pressure,when the concrete is in an unsaturated state,the capillary pressure inside the concrete dominates the ion transport efficiency and shows a significant positive correlation.The higher the permeability coefficient under saturation,the higher the solute flow rate and the higher the efficiency of chloride ion transport.The proposed numerical method based on the finite difference principle is effective.The established nonlinear convection-diffusion erosion model of chloride ions in unsaturated tunnel lining concrete is reliable and it can be used to analyze the transport law of chloride ions in unsaturated concrete.关键词
跨海隧道/非饱和混凝土/氯盐侵蚀/对流-扩散模型Key words
undersea tunnel/unsaturated concrete/chloride erosion/convection-diffusion model分类
建筑与水利引用本文复制引用
石渊博,雷明锋,秦明光,孙宁新,刘凌晖,赵晨阳,贾朝军..考虑非饱和效应的跨海隧道衬砌混凝土氯离子非线性对流-扩散侵蚀模型及其求解方法[J].中南大学学报（自然科学版）,2024,55(3):1035-1045,11.基金项目
国家自然科学基金资助项目(51978669,52378420) （51978669,52378420）
湖南省自然科学基金资助项目(2021JJ30825)(Projects(51978669,52378420)supported by the National Natural Science Foundation of China （2021JJ30825）
Project(2021JJ30825)supported by the Natural Science Foundation of Hunan Province) （2021JJ30825）
