The Impact of Truck Proportion on Traffic Safety Using Surrogate Safety Measures in China

Table 1

The range of basic data collected from different time periods and sections.

Freeway section	Time period (min)	Truck proportion				Traffic volume
		Mean	Std.	Max.	Min.	Mean	Std.	Max.	Min.
Datong	5	0.740	0.168	1.000	0.200	75.850	43.065	195	4
	10	0.728	0.153	0.955	0.222	147.486	80.898	292	7
	15	0.727	0.152	0.968	0.250	221.229	122.259	444	26
Taichang	5	0.286	0.101	0.680	0.044	160.808	44.846	321	7
	10	0.287	0.084	0.571	0.128	309.375	92.765	546	7
	15	0.285	0.078	0.569	0.107	483.082	108.818	750	190
Xinbao	5	0.750	0.128	1.000	0.333	110.250	52.981	258	27
	10	0.754	0.107	0.983	0.533	220.500	97.490	492	65
	15	0.756	0.101	0.974	0.580	330.750	141.523	696	124
Freeway section	Time period (min)	Average speed (km/h)				The number of lane changes
		Mean	Std.	Max.	Min.	Mean	Std.	Max.	Min.
Datong	5	64.110	13.341	98.800	24.545	0.857	1.261	5	0
	10	64.427	12.494	96.419	41.878	1.667	2.214	9	0
	15	64.361	12.352	93.852	39.304	2.500	3.294	17	0
Taichang	5	91.289	10.108	126.313	64.414	1.623	1.802	10	0
	10	90.975	9.670	120.473	69.919	3.123	3.064	17	0
	15	91.257	9.467	121.737	70.945	4.877	4.312	18	0
Xinbao	5	75.693	14.094	98.529	48.503	0.573	0.903	5	0
	10	75.643	13.761	93.847	49.852	1.146	1.502	6	0
	15	75.641	13.906	93.504	50.426	1.719	1.836	8	0