Vedrtnam Ajitanshu, Kalauni Kishor, Palou M T
Institute of Construction and Architecture, Slovak Academy of Science, Bratislava, 84503, Slovakia.
Department of Mechanical Engineering, Invertis University, Bareilly, UP, 243001, India.
Sci Rep. 2025 May 6;15(1):15809. doi: 10.1038/s41598-025-99844-6.
Bacteria-based self-healing concrete has emerged as a promising solution for enhancing structural durability by autonomously repairing cracks. However, the underlying transport mechanisms of healing agents and the efficiency of mineral precipitation remain inadequately modelled. This study presents a finite element modelling (FEM) approach to simulate the diffusion and reaction kinetics of self-healing bacterial agents in concrete microstructures. X-ray micro-computed tomography (Micro-CT) finite element meshes were utilized to accurately represent crack and pore geometries, while the diffusion-reaction equation governing calcium carbonate (CaCO) precipitation was numerically solved using FEniCS. Key input parameters, including diffusion coefficients, precipitation rates, and healing efficiencies, were extracted from literature to ensure model validation. Simulations reveal that healing agent concentration follows a nonlinear diffusion pattern, with efficiency influenced by crack geometry and bacterial metabolic activity. Heatmaps and contour plots highlight healing agent dispersion, while time-dependent analysis indicates a 65.5% crack closure efficiency under optimal bacterial conditions. The proposed model effectively replicates experimental trends, demonstrating its applicability for predicting healing performance in realistic structural conditions. This study provides a computational framework that can be extended to optimize bacteria encapsulation strategies, healing kinetics, and long-term durability assessments in self-healing concrete.
基于细菌的自修复混凝土已成为一种有前景的解决方案，可通过自动修复裂缝来提高结构耐久性。然而，愈合剂的潜在传输机制以及矿物沉淀的效率仍未得到充分建模。本研究提出了一种有限元建模（FEM）方法，以模拟自修复细菌剂在混凝土微观结构中的扩散和反应动力学。利用X射线微计算机断层扫描（Micro-CT）有限元网格来准确表示裂缝和孔隙几何形状，同时使用FEniCS对控制碳酸钙（CaCO）沉淀的扩散-反应方程进行数值求解。从文献中提取关键输入参数，包括扩散系数、沉淀速率和愈合效率，以确保模型验证。模拟结果表明，愈合剂浓度遵循非线性扩散模式，其效率受裂缝几何形状和细菌代谢活性影响。热图和等高线图突出了愈合剂的扩散，而随时间的分析表明在最佳细菌条件下裂缝闭合效率为65.5%。所提出的模型有效地复制了实验趋势，证明了其在实际结构条件下预测愈合性能的适用性。本研究提供了一个计算框架，可扩展用于优化自修复混凝土中的细菌封装策略、愈合动力学和长期耐久性评估。
