水道港口2025，Vol.46Issue(3)：407-418,12.
基于三维随机凹凸骨料的混凝土氯离子扩散细观数值模型
The three-dimensional random aggregate meso-numerical model for chloride ion diffusion in concrete
摘要
Abstract
The mesoscale numerical simulation of chloride ion diffusion in concrete was recognized as a crucial method for studying the durability of reinforced concrete structures in marine environments.The establishment of a reliable mesoscale concrete aggregate model was considered the foundation for conducting numerical simulations.At that time,most existing concrete aggregate models were limited to regular shapes such as circles,regular polygons,or simple convex polygons,which significantly deviated from real-world conditions.Although a few scholars had developed aggregate models incorporating concave polygons,their algorithms were relatively complex.In this paper,the random generation and placement of three-dimensional concave and convex aggregates were realized based on the Monte Carlo method,making the generated aggregates more consistent with the morphological characteristics of actual aggregates while keeping the algorithm concise.Furthermore,the variation in the thickness of the interfacial transition zone(ITZ)was considered by correlating it with the size and morphology of coarse aggregates.The thickness δ of the ITZ at a vertex was defined to be proportional to the distance d from the center of the coarse aggregate to the vertex,with the proportionality coefficient t(i.e.,δ=t×d).The ITZ thickness between two vertices of the coarse aggregate was set to vary linearly.A mesoscale three-dimensional random concave-convex aggregate numerical model for chloride ion diffusion in concrete was established.The reliability of the model was verified by comparing the numerical simulation results with the measured data from physical test models.To address the randomness of the numerical results,100 mesoscale three-dimensional random aggregate models were generated for three coarse aggregate shapes:spheres,convex polyhedrons,and concave-convex polyhedrons.By comparing the coefficients of variation among the simulation results for these three shapes,it is demonstrated that the concave-convex aggregate model proposed in this paper exhibits better stability.关键词
混凝土/细观模型/凹凸骨料/氯离子扩散/数值模拟Key words
concrete/mesoscale model/concave and convex aggregates/chloride ion diffusion/numerical simulation分类
交通工程引用本文复制引用
刘旭颖,王元战,王刚,彭勃..基于三维随机凹凸骨料的混凝土氯离子扩散细观数值模型[J].水道港口,2025,46(3):407-418,12.基金项目
国家重点研发计划项目(2022YFB2603000) （2022YFB2603000）
国家自然科学基金项目(51979191) （51979191）
