Prediction of Compressive Strength of Concrete Using the Spearman and PCA-Based BP Neural Network

Table 1

Samples of proportional data and compressive strength of C40 concrete.

Group number (no.)	1	2	3	…	37	38
Compressive strength (MPa)	51.30	51.90	51.30	…	51.90	52.50
Cement (kg)	640.00	639.68	634.80	…	640.41	639.94
Water (kg)	246.00	230.00	265.77	…	227.99	236.00
Crushed stone 1 (kg)	632.62	638.13	626.40	…	631.86	632.23
Crushed stone 2 (kg)	1060.15	1067.58	1046.93	…	1060.64	1059.92
Crushed stone 3 (kg)	424.00	423.84	418.00	…	433.86	424.23
Sand (kg)	1402.00	1399.87	1366.80	…	1402.47	1410.31
Fly ash (kg)	273.15	274.02	272.50	…	274.04	274.53
Water reducer (kg)	9.15	9.15	9.05	…	9.15	9.13
Cementitious material (kg)	913.15	913.69	907.30	…	876.41	639.94
Four aggregates (kg)	3518.77	3529.42	3458.13	…	3528.82	3526.68
Water-binder ratio	0.27	0.25	0.29	…	0.31	0.43
Sand ratio	0.40	0.40	0.40	…	0.40	0.40
Water-cement ratio	0.38	0.36	0.42	…	0.43	0.43