Table 1.

Index standards.

Evaluation index	Low risk	Medium risk	High risk
Effective value	[0.05, 0.85]	(0.085, 0.1]	(0.1, 1)
Peak factor	[2.5, 3.2]	(3.2, 3.5]	(3.5, 30)
Kurtosis	[2.5, 3.5]	(3.5, 4]	(4, 30)
Wheel diameter	(780, 840]	(775, 780]	[770, 775]
Wheel rim width	(29, 32]	(28, 29]	[26, 28]
Difference of coaxial wheel diameter	[0, 1.5)	[1.5, 2)	[2, 10)
Difference of co-bogie wheel diameter	[0, 3)	[3, 4)	[4, 15)
Traction motor temperature	[0, 70)	[70, 100)	[100, 300)
Brake shoe thickness	[20, 55]	[15, 20)	[0, 15)
Risk of elastic suspension device	[0, 50)	[50, 75)	[75, 100)
Risk of bogie frame	[0, 50)	[50, 75)	[75, 100)
Risk of ground device	[0, 50)	[50, 75)	[75, 100)