Statistical Characteristics of Microhardness of Hardened Cement Paste

来源 :武汉理工大学学报(材料科学版)(英文版) | 被引量 : 0次 | 上传用户:ytx45
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Due to the intrinsic nature of a heterogeneous and anisotropic microstructure of cement based materials and the small indentation size, the measured microhardness values are subject to considerable variability. This work presents an in-depth assessment of microhardness of hardened cement pastes (HCPs) from a statistical perspective. Hundreds of microhardness measurements were conducted on an HCP sample using a Vickers Microhardness Tester. The results showed that the microhardness measured from the HCP sample significantly scattered with a large standard deviation, varying from tens to hundreds. The data-set of microhardness values was not normally distributed but fit best with a three-parameter lognormal model. By using a statistical software, the probability density function of the microhardness distribution can be readily obtained. The arithmetic mean and its 95% confidence intervals of the measured microhardness values can be used to best represent the microhardness characteristics of HCPs.
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