摘要
早期收缩开裂是导致水泥基材料劣化及体积稳定性不良的重要原因。试验设计了干燥收缩、椭圆环约束、测量裂缝平均宽度及强度试验等手段,综合评价了减水剂、减缩剂、膨胀剂在45、55、65℃三种养护温度下对水泥砂浆体积稳定性及强度的影响。结果表明:减水剂、减缩剂和膨胀剂混掺时,在保证原有强度的基础上,可以大幅度降低砂浆的开裂敏感性及早期干燥收缩,使体积稳定性得以显著改善。
Early age cracking caused by shrinkage is an important reason for the deteriorations of cement-based materials and reduction of volume stability.Four check-up experiments are designed in this paper, including drying shrinkage, elliptical ring-restraint, average width of crack and strength test, to investigate the general effect of water-reducing agent（WRA） ,shrinkage-reducing agent（SPA） and expansion agent （EA） on volume stability and strength of cement mortar at different curing temperature（ 45 ℃, 55 ℃ ,65 ℃ ）.The results show that ternary addition of WRA, SPA and EA can decrease cracking sensitivity and early age desiccation shrinkage significantly in promising the foundation of original strength, which improves volume stability obviously.
出处
《混凝土》
CAS
CSCD
北大核心
2007年第3期30-32,35,共4页
Concrete
基金
国家863项目(2005AA332010)
关键词
体积稳定性
早期开裂
椭圆环约束
干燥收缩
养护温度
volume stability
early age cracking
elliptical, ring-restraint
drying shrinkage
curing temperature
