Table 1.

Speed stability and characteristics of different road types in Wuhan, China.

Road Types		Average Speed (km/h)	Speed Stability	Descriptions	Characteristics
Urban roads	Urban rail transit (URT)	40	Stable	Metro; light rail transit (LRT)	No traffic jams and traffic lights
	Freeway	60		Urban high-speed road; ring road	Seldom have traffic jams; no traffic lights
	Major roads	55	Unstable	Arterial road; secondary road	Sometimes have traffic jams; many traffic lights
	Minor roads	40		Tertiary road; fourth-class road; branch road	Sometimes have traffic jams; fewer traffic lights
Rural roads		30	Stable	Rural hardened road	Seldom have traffic jams; no traffic lights