中文核心期刊
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中国科技核心期刊
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重庆交通大学学报（自然科学版）

重庆交通大学学报（自然科学版） ›› 2026, Vol. 45 ›› Issue (9): 60-65.DOI: 10.3969/j.issn.1674-0696.2026.09.07

• 智慧交通基础设施 • 上一篇    

低气压对引气混凝土气孔与孔结构影响研究

刘善利1，马文泰1，陆谦益1，王孟豪1，江朝华2   

  1. (1. 长江南京航道工程局，江苏 南京 211800； 2. 河海大学 港口海岸与近海工程学院，江苏 南京 210024)
  • 收稿日期:2026-03-06 修回日期:2026-07-16 发布日期:2026-09-23
  • 作者简介:刘善利(1980—)，男，山东徽山人，高级工程师，硕士，主要从事水利与岩土工程方面的研究。E-mail： 397654089@qq.com 通信作者：江朝华(1972—)，女，广西合山人，副教授，博士，主要从事近海工程混凝土结构及其耐久性方面的研究。E-mail： chaohuajiang@hhu.edu.cn
  • 基金资助:
    国家自然科学基金面上项目（51679080）

Influence of low pressure on air voids and pore structure of air-entrained concrete

Liu Shanli1, Ma Wentai1, Lu Qianyi1, Wang Menghao1, Jiang Chaohua2   

  1. (1. Nanjing Waterway Engineering Bureau of the Yangtze River, Nanjing 211800, Jiangsu, China; 2. College of Harbor, Coastal and Offshore Engineering, Hohai University, Nanjing 210024, Jiangsu, China)
  • Received:2026-03-06 Revised:2026-07-16 Published:2026-09-23

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摘要： 通过南京（大气压力101.2 kPa）和拉萨（大气压力65.3kPa）两地现场暴露实验，采用气孔参数测试和核磁共振技术，研究了低压环境下不同含气量（3%、 5%、 7%）对引气混凝土气孔及孔结构的影响。结果表明：低气压对引气混凝土的气孔结构具有明显的劣化作用，主要表现为小于200 μm 的气孔比例降低，大于等于200 μm 的气孔比例增加，且变化的程度随混凝土含气量的增加而加剧；较常压条件，低气压条件下成型的3种含气量混凝土的气孔量分别降低了8.3%、9.0%、22.1%，说明高含气量受低气压的影响最大；低气压环境下，即使通过增加引气剂掺量使得混凝土含气量增加，气孔结构参数仍趋劣化，表现为气孔比表面积减小、平均直径增大及气孔数量减少，最终导致气孔间距系数增加；低气压和常压环境下成型的引气混凝土，其总孔隙率均随含气量增加而上升；低压条件下成型的混凝土中，大于200 nm的毛细孔数量更多，导致总孔隙率增加。

关键词: 岩土工程；低气压；混凝土；气孔结构；孔结构

Abstract: Based on field exposure experiments conducted in Nanjing (101.2 kPa) and Lhasa (65.3 kPa), the effect of different air contents (3%, 5%, and 7%) on air voids and pore structures of air-entrained concrete under low-pressure environment was studied by air voids parameter test and nuclear magnetic resonance (NMR) techniques. The results show that low pressure significantly deteriorates the air-void structure of air-entrained concrete, primarily manifested by a decrease in the proportion of air voids smaller than 200 μm and an increase in the proportion of those larger than or equal to 200 μm, and the degree of change intensifies as the concrete air content increases. Compared with normal atmospheric pressure conditions, the porosity of three types of air-entrained concrete cast under low-pressure conditions decreases by 8.3%, 9.0%, and 22.1%, respectively, with high air content being most affected by low-pressure conditions. In low-pressure environment, even when the concrete air content is increased by adding a higher dosage of air-entraining agent, the air-void structure parameters still deteriorate, characterized by a reduction in the specific surface area of air voids, an increase in average diameter, and a decrease in the number of air voids, ultimately causing an increase in the pore spacing coefficient. The total porosity of air-entrained concrete cast under both low and normal atmospheric pressures rises as the air content increases. Concrete cast under low pressure conditions contains more capillary pores larger than 200 nm, thereby increasing the total porosity.

Key words: geotechnical engineering; low pressure; concrete; air-void structure; pore structure

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