关键词: 高性能混凝土, 等强度设计, 胶凝材料影响系数, 抗裂性 

Abstract:

In order to avoid influence of different concrete strength on crack resistance evaluation, the mixing ratio design of high performance concrete (HPC) based on equivalent strength was introduced. Two 50MPa HPC examples, single doped by 40% fly ash of, compound doped by 5% silica powder and 35% fly ash, were employed to conduct the mixing ratio design based on equivalent strength and their crack resistances were compared. The results indicated that the design of equivalent strength HPC by using cementing material coefficient is feasible; the cementing material coefficient of 1.04 for 5% silica powder example is suitable; under equivalent strength condition, the crack resistance of different concretes varied. Compared with the concrete of 40% fly ash single doped, the equivalent strength concrete of 5% silica powder and 35% fly ash compound doped has larger drying shrinkage, lower ultimate tension and higher cracking sensitivity.

Key words: high performance concrete(HPC), equivalent strength design, cementing material coefficient, crack resistance