Home Engineering Creep Behaviour in Cracked Sections of Fibre Reinforced Concrete: Proceedings of the International RILEM Workshop FRC-CREEP 2016
Overview of Data and Methodology
Summary of the Information Collected
This research was based on the creep test results corresponding to 118 FRC specimens, tested under sustained flexural loads for at least 90 days. For each of these cases, the information collected included parameters concerning the following aspects:
Representative values for each of the variables are given in Table 1 for reference. Minimum, average and maximum values were intended to be descriptive of the entire set of data and were calculated as the 5, 50, and 95 % percentiles. The percentage of missing values for each variable represents those cases for which complete information could not be obtained.
Table 1 Summary of the information in the database
Treatment of Missing Values
As the sources of these data did not always report the mix characteristics, their flexural response or their flexural creep behaviour in the same way, some of the values of interest had not been reported.
This is quite common in the context of data mining applications or multivariate statistics , and different strategies can be adopted to moderate the impact of missing cases on the reliability of the information that can be extracted from a set of data. In this case, the prevalence of missing values was relatively small and did not justify complete elimination of any cases. Instead, a multiple imputation by fully conditional specification  was done to simulate the missing values taking advantage of the multiple correlations between the different variables.
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