摘要
通过绝热温升、平板开裂、温度-应力开裂、收缩徐变及氯离子扩散系数、电通量、抗冻性等试验,对比研究了4个箱梁C55混凝土配合比的早期开裂敏感性与长期变形性能及耐久性。结果表明,在箱梁C55高性能混凝土中掺入20%Ⅰ级粉煤灰或复掺15%粉煤灰与10%矿粉,提高了抗塑性收缩开裂和抗热开裂性能,降低了收缩徐变,增强了抗氯离子渗透性和抗冻性。掺入0.75 kg/m3的聚丙烯纤维,进一步改善了箱梁混凝土的抗裂性和耐久性。
The early stage cracking sensitivity,long-term deformation and durability of four C55 high performance concrete（HPC） mixtures were investigated by means of these tests such as adiabatic temperature rise,flat test for inducing crack and temperature-stress crack,shrinkage and creep,and chloride diffusion coefficient,electric flux as well as frost resistance.Results show that the C55 HPC mixture incorporating with 20% fly ash（FA） or the composites of 15% FA and 10% granulated blaster furnace slag（GBFS） had higher resistance to plastic shrinkage cracking and heat cracking as well as less deformations of dry shrinkage and creep.Meantime,the incorporation of FA or FA and GBFS improved chloride penetration resistance and freeze-thaw durability of the C55 HPC mixture.Moreover,the incorporation of 0.75 kg/m3 polypropylene fibre further reinforced the crack resistance and durability of the box girder concrete.
出处
《武汉理工大学学报》
CAS
CSCD
北大核心
2010年第14期40-44,共5页
Journal of Wuhan University of Technology
基金
交通部科技项目(2007353342180)
关键词
箱梁
高性能混凝土
抗裂
收缩徐变
耐久性
box girder
high performance concrete
crack resistance
shrinkage and creep
durability
