研究了硬化水泥石样品表面平整度和含水状态对其微观形貌、显微硬度及统计分布的影响。结果表明:硬化水泥石显微硬度数据呈明显的离散分布特征,提高样品表面平整度可在一定程度上降低显微硬度数据的离散性,但对硬化水泥石进行有限次的显微硬度测试时,不论抛光与否,数据均不符合正态分布,而更加符合3因数对数正态分布。采用3因数对数正态分布对相同原材料、配比、养护和制样方法制备的硬化水泥石显微硬度进行统计分析后发现,饱和面干硬化水泥石的显微硬度明显低于干燥状态的样品。因此,当测试水泥基材料的显微硬度时,必须要保持待测样品表面具有相同的平整度和水饱和程度,并应采用统计方法对数据进行比较和分析。
Influences of smoothness and saturation level of hardened cement paste (HCP) on its microscopic morphologies, microhardness and statistic distribution were investigated. The results indicate that the measured microhardness values are subject to considerable variability, and the improvement of the sample smoothness can slightly lead to the less variability of microhardness values. However, for limited microhardness measurements, the microhardness data are not normally-distributed, but fit best with a 3-parameter lognormal model. For the same HCP samples with different water saturation levels, it is clear that the microhardness of saturated surface-dried (SSD) samples is lower than that of oven-dried samples after quantitatively comparing the statistical parameters to the best goodness-of-fit of 3-parameter lognormal distribution. It is essential to keep the sample with the same surface condition, and it is necessary to statistically analyze the microhardness of cement based materials.