Prediction of Compressive Strength of Concrete in Wet-Dry Environment by BP Artificial Neural Networks

Table 4

Kendall and Spearman correlation coefficients of influencing factors.

Correlation coefficient	Specific surface area	Initial strength	FA dosage	Slag dosage	Sodium ions	Magnesium ions	Chloride ions	Sulfate ions	Exposure age
Kendall	0.01	0.406	0.172	0.04	0.00	0.180	0.01	0.00	0.078	0.483
Spearman	0.00	0.577	0.226	0.05	0.00	0.243	0.02	0.00	0.126	0.627

This factors has a quite high relevance with the final strength.