含气量对低温养护下混凝土孔结构的研究  

Effects of air content on concrete pore structure under low temperature curing

作　　者：张凯[1] 王起才[1] 王庆石[1] 李伟龙[1] 李建新[1] 

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070

出　　处：《混凝土》2015年第4期49-52,共4页Concrete

基　　金：长江学者和创新团队发展计划资助(IRT1139);国家自然科学基金资助项目(51268032);铁道部科技研究开发计划项目(2010G019-A)

摘　　要：以低温(3±0.2)℃养护下引气混凝土为研究对象,采用压汞法、气孔分析法、快速冻融法测试了不同含气量低温养护下混凝土的孔隙结构及抗冻耐久性,此外,还分析了不同含气量下混凝土的抗压强度。结果表明:掺入引气剂时,在混凝土含气量增加的同时,可使低温养护下混凝土孔隙率、总孔体积、总孔面积增加,平均孔径、孔间距系数减小,孔径均匀分布,显著改善混凝土的内部孔隙结构,提高混凝土的抗冻耐久性,但受强度影响,混凝土的含气量存在一个合理范围,既可以提高混凝土的抗冻耐久性,又不会造成强度的大幅损失。It tested the pore structure and freeze-proof durability of concrete under lowtemperature curing and with different air contents by taking air-entrained concrete under lowtemperature curing（ 3 ± 0.2） ℃ as research object and by adopting mercury intrusion method,pore analytical method and fast freezing-thawing method. In addition,it also analyzed the compressive strength of concrete with different air contents. Experimental results showthat when air entraining agent is added and concrete of lowtemperature curing under different air content is increased,concrete porosity,total pore volume and total pore area increased,while average pore size and hole pitch coefficient decreased. The distribution of pore diameter was uniform. The interior pore structure of concrete was improved significantly and the freeze-proof durability of concrete was improved,but the air content of concrete was in a reasonable scope influenced by strength,which not only improved the freeze-proof durability of concrete but also prevented the substantial losses of strength.

关 键 词：混凝土 低温养护 含气量 孔隙结构 抗冻耐久性 

分 类 号：TU528.01[建筑科学—建筑技术科学]