Correlation Analysis of External Environment Risk Factors for High-Speed Railway Derailment Based on Unstructured Data

Table 1

Main external environmental factors associated with derailment of high-speed railway.

No.	Serial number	Class I factors	Class II factors	Name of related factors
1	Z11	Natural and geological factors	Natural hazard factors	Earthquake
2	Z12			Flood
3	Z13			Strong wind (gale, typhoon, and tornado)
4	Z14			Blizzard (ice)
5	Z21		Geological hazard factors	Collapse
6	Z22			Landslide
7	Z23			Debris flow
8	Z24			Ground collapse
9	Z25			Ground fissure
10	Z26			Land subsidence
11	Y11	Perimeter intrusion factors	Perimeter intrusion of animals	Collision with livestock
12	Y12			Collision with other animals
13	Y21		Perimeter intrusion of objects and plants	Falling objects
14	Y22			Dangerous trees
15	Y23			Tower not satisfying lodging distance
16	Y24			Objects (a vehicle) slide into a track
17	Y25			Tools and equipment left behind
18	Y26			Obstacles artificially placing on the track
19	Y31		Perimeter intrusion of people	Suicide (including attempted suicide)
20	Y32			Fall off the platform
21	Y33			Crossing the track illegally
22	Y34			Disabled people without care