Sustainable Highway Design: Disentangling the Effects of Geometric-Related and Traffic-Related Factors on Urban Highway Traffic Emissions

Table 3

Simulation results of different factors.

Number	Influencing factors		HC (g/mile)	CO (g/mile)	NOx (g/mile)	Delay (s)	Average speed (mph)
1	Lane width (ft)	10	0.16	13.01	0.69	48.37	23.04
		11	0.16	12.97	0.69	47.72	23.11
		12	0.16	13.03	0.69	48.00	23.08
		13	0.16	13.05	0.69	46.54	23.24
2	Number of vehicle lanes	4	0.17	13.51	0.75	57.42	22.09
		6	0.16	13.03	0.69	48.00	23.08
		8	0.15	12.74	0.67	43.09	23.63
3	Exclusive lane set	Original	0.16	13.03	0.69	48.00	23.08
		Remove left turn pocket	0.17	13.52	0.73	57.48	22.06
		Remove right turn pocket	0.16	12.98	0.69	49.39	22.93
		Remove both pockets	0.17	13.59	0.73	62.11	21.61
4	Free-flow speed (mph)	30	0.16	13.03	0.69	48.00	23.08
		35	0.20	16.25	0.82	45.29	25.57
		40	0.25	19.64	1.01	45.67	27.74
		45	0.30	23.30	1.19	45.06	29.58
		50	0.36	27.93	1.39	49.52	30.28