Fuzzy Risk Assessment of Tunnels’ Undercrossing Existing Structures

Table 1

Risk grade classification of safety risk assessment index of the tunnel undercrossing the railway blasting construction.

Risk level	Interval differentiate	Cloud digital eigenvalues
Low risk I	[0, 2)	(0.1, 0.3333, 0.0333)
Lower risk II	[2, 4)	(0.3, 0.3333, 0.0333)
Medium risk III	[4, 6)	(0.5, 0.3333, 0.0333)
High risk IV	[6, 8)	(0.7, 0.3333, 0.0333)
Extremely high risk V	[8, 10]	(0.9, 0.3333, 0.0333)