摘要
通过快冻法试验研究了掺入钢纤维和聚丙烯纤维及纤维掺量对C50高性能混凝土抗冻性的影响;利用扫描电子显微镜观察了纤维-基材界面区的微观结构,从微观结构角度分析了抗冻性试验的结论。结果表明:虽然钢纤维-基材界面区的微观结构优于聚丙烯纤维-基材界面区,但聚丙烯纤维对混凝土抗冻性的改善效果优于钢纤维;聚丙烯纤维对混凝土抗冻性的影响存在阻裂效应和弱界面效应双重作用,存在最佳纤维掺量;掺入1.0%聚丙烯纤维对混凝土抗冻性提高效果最好,300次冻融循环后相对动弹性模量高达98.01%。
Effects of adding steel fibers and polypropylene fibers into C50 high performance concrete and different fiber contents on frost resistance of concrete were investigated by fast frost test.The microstructures of fiber-matrix interface zones were observed by using scanning electron microscopy,so that the results of macro-frost tests were analyzed from the microstructure point of view.Results showed that by adding polypropylene fibers,the improving effects on frost resistance of concrete was better than by adding steel fibers,although the latter was of better microstructures of fiber-matrix interface zone.When adding polypropylene fibers into concrete,there were double effects including,which was crack resistance effect and weak interface zone effects,so that the optimum fiber volume content existed.Adding 1.0 % polypropylene fibers into concrete could achieve the best improving effect of frost resistance,and the relative dynamic elastic modulus was high to 98.01 % after 300 times of freeze-thaw cycles.
出处
《南京林业大学学报(自然科学版)》
CAS
CSCD
北大核心
2010年第5期91-95,共5页
Journal of Nanjing Forestry University:Natural Sciences Edition
基金
南京工程学院科研基金项目(KXJ08044)
关键词
高性能混凝土
抗冻性
微观结构
钢纤维
聚丙烯纤维
纤维掺量
high performance concrete
frost resistance
microstructure
steel fiber
polypropylene fiber
fiber content