Liu Lan, Guo Taidong, Cheng Zhi, Wang Zhongzhen, Cheng Xiaozhi, Cheng Zhijun, Ma Zhe
School of Environment and Safety Engineering, North University of China, Taiyuan 030051, China.
China Power Construction Group Northwest Survey Design and Research Institute Co., Ltd., Xi'an 710065, China.
Materials (Basel). 2025 Mar 7;18(6):1189. doi: 10.3390/ma18061189.
This study utilized CT scanning and image processing techniques to extract and analyze the internal mesostructure and cement paste distribution of porous concrete. The effects of the mesostructure and cement paste distribution on the compressive strength and permeability were studied. Additionally, the research explored the blockage mechanisms and morphology in porous concrete, with CT scanning used to map the distribution of blockages within the material. The results indicate that the impact of the aggregate particle size on the compressive strength is much less significant than the effect of porosity. The images clearly show that the pore size is positively correlated with both porosity and aggregate size. Additionally, the distributions of pore size and cement paste thickness can be described using a lognormal distribution function and a two-parameter Weibull function, respectively. Blockage analysis revealed that the blockages were primarily concentrated within the top 0-30 mm of the porous concrete surface. As the pore size increases, the blockage depth increases, and blockages in the 10-30 mm range are challenging to remove with high-pressure water jets. A degradation model for the permeability performance of aggregate porous concrete, considering blockage consolidation, was established using parameters such as the blockage accumulation per unit area, aggregate particle size, and concrete porosity. This model provides theoretical and data-based references for evaluating the service life of porous concrete.
本研究利用CT扫描和图像处理技术来提取和分析多孔混凝土的内部细观结构和水泥浆体分布。研究了细观结构和水泥浆体分布对抗压强度和渗透性的影响。此外，该研究还探究了多孔混凝土中的堵塞机理和形态，利用CT扫描来绘制材料内部堵塞物的分布情况。结果表明，集料粒径对抗压强度的影响远不如孔隙率的影响显著。图像清楚地表明，孔径与孔隙率和集料尺寸均呈正相关。此外，孔径分布和水泥浆体厚度分布可分别用对数正态分布函数和双参数威布尔函数来描述。堵塞分析表明，堵塞物主要集中在多孔混凝土表面顶部0至30毫米范围内。随着孔径增大，堵塞深度增加，10至30毫米范围内的堵塞物难以用高压水射流清除。利用单位面积堵塞物累积量、集料粒径和混凝土孔隙率等参数，建立了考虑堵塞固结的集料多孔混凝土渗透性能退化模型。该模型为评估多孔混凝土的使用寿命提供了理论和数据参考。
