Neural Network Based Estimation of Service Life of Different Metal Culverts in Arkansas

Table 1

Summary of SSURGO data of Arkansas.

Field	Min.	Max.	Mean	Standard deviation
CaCo3	0.00	14.00	0.06	0.45
Cation exchange capacity (meq/10 g)	0.00	57.50	7.38	10.18
Effective cation exchange capacity (meq/10 g)	0.00	56.70	10.71	8.28
Electric conductivity (mmhos cm^−1)	0.00	8.60	0.20	0.56
Gypsum	0.00	3.00	0.02	0.21
pH	4.30	8.30	5.35	0.65
Sodium absorption ratio	0.00	16.50	0.09	0.78
Liquid limit	4.90	85.00	36.75	11.20
Organic matter content	0.02	4.40	0.66	0.43
Clay (%)	3.50	73.00	28.50	11.67
Sand (%)	1.50	95.00	31.02	19.63
Silt (%)	0.60	77.40	40.45	16.30
Plasticity index	0.00	58.70	16.92	8.80
Hydraulic conductivity (micrometers per second)	0.14	92.00	9.51	12.84
Depth of water table (cm)	0.00	>201	118.18	76.52