不同亲水性能的纤维对混凝土抗冻耐久性的影响  

Influence of Fiber Hydrophilic to Improve the Frost Resistance of Concrete

作　　者：何柏[1,2] 谢凌志[1,2] 刘泉 张生 

机构地区：[1]四川大学能源工程安全与灾害力学教育部重点实验室,四川成都610065 [2]四川大学新能源与低碳技术研究院,四川成都610207 [3]四川省交通勘察设计研究院,四川成都610017

出　　处：《四川大学学报（工程科学版）》2016年第2期225-230,共6页Journal of Sichuan University (Engineering Science Edition)

基　　金：四川交通科技资助项目(2011c15_2_2)

摘　　要：为了研究不同亲水性能的纤维对混凝土抗冻性能的影响规律,选择3种不同回潮率的纤维,采用快冻法对纤维混凝土的抗冻耐久性进行试验研究;分析不同纤维混凝土的冻融损伤规律,以及回潮率对其冻融损伤的影响。利用SEM对冻融前后纤维-水泥石基体进行了观测,进一步探讨纤维亲水性对混凝土抗冻性能的影响机理。结果表明,亲水性良好的纤维能够与水泥石更好的共同作用,有效抑制混凝土内部初期微缺陷及冻融过程中微缺陷的生长;而疏水性纤维难以与水泥石难以形成有效的共同作用体系,对于冻融循环过程中微缺陷的生长抑制能力较弱,其纤维-水泥石之间的薄弱带甚至可能会加速混凝土的冻融损伤;且随着冻融循环次数的增加,纤维的亲水性对混凝土的抗冻性能影响愈加明显。Three kinds of fibers with different rate of moisture regain were selected to study the effect of hydrophilism of fibers on the durability of fiber reinforced concrete during freeze-thaw with the rapid freeze-thaw cycle experiment. Microstructure of fiber-cement matrix were observed using SEM before and after freeze-thaw. The results showed that compared with the hydrophobic fibers,since the latter can be tightly bonded with cement matrix together hydrophilic fibers can effectively inhibit the initial micro-defects of concrete and prevent the growth of micro-defects in the freeze-thaw cycles. Therefore,hydrophobic fiber concrete may even accelerate the growth of damage during freeze-thaw cycles,due to the interfacial performance between fibers and concrete is weak. With the increase of freezethaw cycles,the impact on frost resistance of concrete by the hydrophilic of fibers became more and more obvious.

关 键 词：亲水性 疏水性 冻融 回潮率 纤维混凝土 

分 类 号：TU528.2[建筑科学—建筑技术科学]