混凝土单轴受压全过程变异性试验研究

为了研究混凝土在单轴受压作用下的全过程受力特征,通过对强度等级为C30~C60的60个混凝土棱柱体试件进行单轴受压应力-应变全曲线试验,得到了单轴受压作用下混凝土峰值强度、峰值应变、弹性模量和应力-应变全曲线的统计特征.根据混凝土结构设计规范(GB50010—2010)中的混凝土峰值强度变异系数,利用概率密度演化方法,获得了混凝土应力均值曲线和应力标准差曲线.通过与试验结果进行对比,认为仅用峰值强度的变异系数不足以描述混凝土应力-应变全过程的随机性,建议给出标准差曲线.

Experimental Study of Full Process Variability of Concrete Under Uniaxial Compression

An experimental research was performed to investigate the behavior of concrete under uniaxial compression. A total of 60 prism specimens of which the strength grade ranges from C30 to C60 were tested using the MTS testing system. Based on the experimental results, the statistical characteristics of peak strengths, peak strains elastic modules and the complete stress strain curves were obtained. Then, the randomness of concrete was studied theoretically according to the variation coefficient of strength specified in Chinese code (GB50010 2010). The mean curves and standard deviation curves were obtained based on the generalized probability density evolution method. The comparison between the experimental and theoretical results indicate that it is inadequate to represent the randomness of concrete only by the variation coefficient of strength. Finally, the standard deviation curves were proposed based on experiment results.