纤维素纤维引气混凝土的耐久性及气孔结构研究  

Durability and Stomatal Structure of Cellulose Fiber Air Entrained Concrete

作　　者：马超 朱健 MA Chao;ZHU Jian(Guangdong Changda Road Maintenance Co.,Ltd.,Guangzhou 510000,China;Foshan University,Foshan 528051,China)

机构地区：[1]广东长大道路养护有限公司,广州510000 [2]佛山大学,佛山528051

出　　处：《硅酸盐通报》2024年第11期4047-4054,共8页Bulletin of the Chinese Ceramic Society

摘　　要：为了弥补引气剂造成的强度损失,进一步提高混凝土的耐久性,在混凝土中加入纤维素纤维和引气剂,研究了纤维素纤维掺量(0.08%~0.12%,体积分数)和含气量(2%~4%)对混凝土力学性能的影响,确定了引气混凝土的含气量。通过塑性收缩试验、抗渗试验、硫酸盐-干湿循环试验和冻融试验,研究了纤维素纤维对引气混凝土耐久性的影响。结合气泡间距分析试验,分析了纤维素纤维引气混凝土的气孔结构。结果表明,引气剂的加入降低了混凝土的力学性能,纤维素纤维提高了混凝土的力学性能,混凝土的含气量不宜大于3%。纤维素纤维可以提高引气混凝土的抗收缩性、抗渗性、抗硫酸盐侵蚀性和抗冻性。当纤维素纤维掺量为0.10%时,纤维素纤维引气混凝土的力学性能和耐久性均最佳。引气剂明显改善了混凝土的气泡体系特征,当含气量大于或等于3%时,纤维素纤维引气混凝土的气泡间距系数均小于250μm。In order to compensate for the strength loss caused by air entraining agent,and further improve the durability of concrete,the effects of cellulose fiber content(0.08%~0.12%,volume fraction)and air content(2%~4%)on the mechanical properties of concrete were studied by adding cellulose fiber and air entraining agent to concrete,and the air content of air entrained concrete was determined.The effect of cellulose fiber on the durability of air entrained concrete was studied by plastic shrinkage test,impermeability test,sulphate-wet and dry cycle test and freeze-thaw test.Combined with the bubble spacing test,the stomatal structure of cellulose fiber air entrained concrete was analyzed.The results show that the addition of air entraining agent can reduce the mechanical properties of concrete,the cellulose fiber can improve the mechanical properties of concrete,and the air content of concrete should not be more than 3%.Cellulose fiber can improve the shrinkage resistance,impermeability,sulfate erosion resistance and freezing resistance of air entrained concrete.When the cellulose fiber content is 0.10%,the mechanical properties and durability of cellulose fiber air entrained concrete are the best.The air entraining agent can obviously improve the characteristics of bubble system of concrete.When the air content is more than or equal to 3%,the bubble spacing coefficient of cellulose fiber air entrained concrete is less than 250μm.

关 键 词：引气混凝土 纤维素纤维 力学性能 耐久性 气孔结构 

分 类 号：TU528[建筑科学—建筑技术科学]