混杂纤维混凝土早龄期抗裂性能试验研究  

Experimental Research of Crack Resistance of Hybrid Fiber Reinforced Concrete at Early Age

作　　者：邢通[1] 曹晨杰[1] 宋丽莎[1] 孙丽[1] 霍洪媛[1] 

机构地区：[1]华北水利水电学院土木与交通学院,河南郑州450045

出　　处：《华北水利水电学院学报》2013年第1期50-53,共4页North China Institute of Water Conservancy and Hydroelectric Power

基　　金：河南省教育厅自然科学研究计划项目(2010A570002);清华大学水沙科学与水利水电工程国家重点实验室开放基金(sklhse-2008-D-02)

摘　　要：选取强度等级CF40和CF50混凝土,在混杂纤维混凝土配合比三元叠加法试验基础上确定配合比:在钢纤维体积分数固定为1%时,聚丙烯纤维掺量在0.3～1.5 kg/m3内按级差0.3 kg/m3取5个水平;在聚丙烯纤维掺量为0.9 kg/m3时,钢纤维体积分数在0.5%～2.0%内按级差0.5%取4个水平,研究纤维的不同掺量对混凝土早龄期抗裂性能的影响以及试件裂缝形态的变化.结果表明,钢-聚丙烯纤维混杂具有耦合提高混凝土早龄期抗裂性能的作用,早龄期抗裂性能随纤维掺量的增加而提高;钢纤维体积分数和聚丙烯纤维掺量存在合理有效值.纤维混杂可以协同阻裂和限裂,使混凝土裂缝由宽、长形态调整为细、短形态.The mix proportions of hybrid fiber reinforced concrete with strength grades of CF40 and CFS0 were designed according to the superposition mix design method, in which five levels of the polypropylene fiber content were selected in the range from O. 3 kg/m3 to 1.5 kg/ma with the increment of O. 3 kg/m3 as the volume fraction of steel fiber was constant at 1.0% , and four levels of volume fraction of steel fiber were chosen in the range from 0.5% to 2.0% with the increment of 0.5% as the content of polypropylene fiber was kept in 0.9 kg/m3. The effects of different contents of fiber on the crack resistance of concrete at early age and the crack states variation of specimens were studied. The results showed that the hybrid of steel fiber and polypropylene fiber had coupling effects on improving the crack resistance of concrete at early age, and the crack resistance raised with the increase of fiber contents. The results also indicated that there were the rational and effective values of the volume fraction of steel fiber and the content of polypropylene fi- ber, and the fiber hybrid could collaboratively prevent and limit the cracks, which made thin and short cracks change into wide and long shape.

关 键 词：混杂纤维混凝土 钢纤维 聚丙烯纤维 早龄期 抗裂性能 

分 类 号：TU528.572[建筑科学—建筑技术科学]