钢纤维纳米矿粉混凝土凝结时间与强度研究  

Research on setting time and strength of steel fiber and nanometer materials reinforced concrete

作　　者：杨静[1] 李晗[2] 杨林[3] 

机构地区：[1]郑州市规划勘测设计研究院,河南郑州450052 [2]郑州大学新型建材与结构研究中心,河南郑州450002 [3]黄河勘测规划设计有限公司,河南郑州450003

出　　处：《混凝土》2015年第8期66-70,共5页Concrete

基　　金：国家自然科学基金项目(51178434)

摘　　要：将钢纤维和纳米矿粉(纳米Si O2、纳米Ca CO3)同时掺入混凝土中配制出钢纤维纳米混凝土(steel fiber and nanometer materials reinforced concrete,简称SFNM RC)。通过SFNM RC凝结时间和3、7、28 d龄期立方体抗压强度试验,分析钢纤维、纳米Si O2、纳米Ca CO3对SFNMRC凝结时间及强度的影响,并通过扫描电镜分析,探讨纳米Si O2、纳米Ca CO3对SFNMRC强度的影响机理。结果表明:纳米Si O2能明显缩短SFNMRC初凝和终凝时间;纳米Ca CO3能明显降低SFNMRC的初凝时间,但对终凝时间影响不显著。钢纤维对SFNMRC 3、7、28 d龄期增强作用基本相同;纳米Si O2和纳米Ca CO3能提高SFNMRC各龄期抗压强度,纳米Si O2对SFNMRC低、中龄期(3、7 d)强度提高较明显,纳米Ca CO3对SFNMRC低龄期(3 d)强度提高较明显。最后,建立了考虑龄期、钢纤维体积率、纳米矿粉掺量等影响的SFNMRC立方体抗压强度计算模型。Through setting time and compressive strength tests of fiber and nanometer materials reinforced concrete （ SFNMRC ）, the effects of steel fiber volume fraction, replacement rate of cement by nanometer materials on SFNMRC setting time and compressive strength were investigated.The effect mechanisms of nano - SiO2 and nano - CaCO3 were analyzed by scanning electron micrograph （SEM） .The initial and final setting time of SFNMRC declined sharply when the content of nano- SiO~ increased.Nano- CaCO3 could significantly reduce initial setting time, but its influence was not notable on final setting time. Steel fiber could improve SFNMRC strength at different ages. The strength of SFNMRC, especially at 3 d and 7 d age,increased as the content of nano - SiO2 increased. The compressive strength of SFNMRC, especially at 3 d age,increased as the content of nano - CaCO3 increased.An analytical model for the compressive strength of SFNMRC was proposed.

关 键 词：钢纤维 纳米SIO2 纳米CACO3 凝结时间 抗压强度 龄期 

分 类 号：TU528.041[建筑科学—建筑技术科学]