Nonparametric Binary Recursive Partitioning for Deterioration Prediction of Infrastructure Elements

Table 2

Indiana bridge inventory characteristics from the last inspection.

Network assessment		Highway class
		NHS	Major STP	Minor STP	Local
Average bridge age (year)		31	37	34	36
Clear deck width distribution (%)	≤ 12 ft	1	2	4	29
	≤ 13 ft	3	3	3	16
	≤ 14 ft	4	4	5	16
	≤ 15 ft	6	7	3	3
	≤ 16 ft	6	5	7	14
	> 16 ft	80	79	66	15
Deck condition distribution (%)	Good	70	65	69	63
	Satisfactory	16	26	22	27
	Fair	2	7	6	7
	Poor	1.5	1.5	2	2
	Serious	0.5	0.5	1	1
Superstructure condition distribution (%)	Good	85	74	74	81
	Satisfactory	9	18	17	10
	Fair	3	4	4	5
	Poor	2.5	3	3	2
	Serious	0.5	1	2	2
Substructure condition distribution (%)	Good	85	71	68	80
	Satisfactory	8	21	21	11
	Fair	5	6	8	5
	Poor	1.5	1	2	2
	Serious	0.5	1	1	2
Inventory load rating distribution (%)	IR ≤5 tons	0.2	0.2	0.2	1.5
	5 < IR ≤15 tons	0.2	0.2	0.2	1.5
	15 < IR ≤25 tons	3.6	5	7.6	8
	25 < IR ≤30 tons	11	14	12	5
	30 < IR ≤35 tons	19	19.6	18	16
	35 < IR ≤40 tons	45	44	47	42
	IR >40 tons	21	17	15	26