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

Table 9

Error percentage of actual values and prediction values.

Actual values (MPa)	36.93	55.53	88.43	37.72	54.76	86.45	36.04	56.54	87.86
Prediction values (MPa)	37.44	53.71	88.22	37.45	55.50	87.64	37.46	56.65	87.26
Error percentage (%)	1.39	−3.27	−0.24	−0.72	1.34	1.37	3.93	0.19	−0.68
Actual values (MPa)	37.26	55.89	88.79	38.29	55.18	86.77	36.72	57.02	88.28
Prediction values (MPa)	37.41	56.31	88.18	37.98	55.45	87.84	37.51	56.51	88.50
Error percentage (%)	0.40	0.75	−0.69	−0.81	0.49	1.24	2.14	−0.89	0.24
Actual values (MPa)	37.88	56.12	89.01	38.85	55.54	87.02	37.39	57.53	88.69
Prediction values (MPa)	37.55	56.55	88.04	39.10	55.06	88.26	37.15	57.15	88.80
Error percentage (%)	−0.87	0.76	−1.09	0.65	−0.87	1.42	−0.63	−0.67	0.12
Actual values (MPa)	38.31	56.53	89.27	39.36	55.92	87.31	36.58	58.02	89.11
Prediction values (MPa)	37.99	56.68	87.73	38.62	55.56	88.63	36.97	57.83	89.04
Error percentage (%)	−0.82	0.27	−1.72	−1.87	−0.64	1.52	1.06	−0.33	−0.08
Actual values (MPa)	38.66	56.86	89.53	38.53	56.27	87.58	35.82	58.51	89.51
Prediction values (MPa)	38.27	57.45	87.10	38.08	56.86	88.97	36.90	57.82	89.25
Error percentage (%)	−1.00	1.04	−2.71	−1.18	1.05	1.58	3.02	−1.18	−0.28