Title: Discussion on Problem of Standard Deviation of Concrete Strength

Author(s): Dai Zhenchao

Publication: Materials Journal

Volume: 117

Issue: 1

Appears on pages(s): 25-35

Keywords: empirical equation of concrete strength; error transmission; linear relationship; normal distribution; χ2 distribution

DOI: 10.14359/51718053

Date: 1/1/2020

Abstract:
This paper discusses the characteristics of the standard deviation of concrete specimen strength and the relationship between the standard deviation of concrete strength and the average value of strength. It is revealed that strength standard deviation of a small number of specimens is highly uncertain and can neither represent nor be used to predict the actual strength standard deviation of concrete. The results of theoretical calculation and practical measurement show that the standard deviation of strength increases with the increase of the average strength, which is close to linear relationship, but when the strength equals zero, the standard deviation of strength still exists.