掺超细粉煤灰高性能混凝土应力-应变全曲线试验研究

Experimental Research on Stress-strain Curves of High Performance Concrete with Ultra-fine Fly Ash

对5组132块C60～C80掺超细粉煤灰高性能混凝土试件和2组33块C50～C60普通混凝土试件进行单轴受压试验,测得了其应力应变全曲线并进行了理论分析和比较.给出了掺超细粉煤灰高性能混凝土棱柱体强度、峰值应变、弹性模量与立方体强度的关系,并与普通混凝土进行了对比.掺超细粉煤灰高性能混凝土应力应变全曲线与普通高强混凝土相似;给出了适用于不同强度等级粉煤灰高性能混凝土的受压应力应变全曲线统一数学表达式,其理论曲线与试验曲线吻合较好.

The stressstrain curves of C60～C80 highperformance concrete (HPC) with ultrafine fly ash (UFA) in total of 5 groups with 132 specimens are conducted under uniaxial compression . The complete stressstrain curves are analysed and compared theoretically. The relationship between the prismatic strength and the cubic strength is obtained .The empirical formulas of the peak strain and the modulus of elasticity are established . At the same time, 2 groups with 33 specimens C50～C60 ordinary concrete are tested. The stressstrain curves of HPC with UFA are compared with that of ordinary concrete .The results show that the stressstrain curves of HPC are basically similar to ordinary concrete. A unified numerical expression of uniaxial compressive stressstrain curves applicable to all grades of HPC with UFA is put forward. The theoretical curves are in good agreement with the experimental curves. 