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Three cases involving different timing plans will be examined in this sub-problem: The first will use the optimal timings from Sub-problem 5b. The difference in the results will be due solely to differences in the HCM treatment of traffic-actuated control. The results are summarized in Exhibit 3-40.

Note that there were no differences in the v/c ratio, g/c ratio, or uniform delay values in the comparison of pre-timed and traffic-actuated operation. The k values were all 0.5 for pre-timed control and 0.37 for traffic-actuated control. The reduction in the k values produced a slight decrease in the incremental delay for all movements, and this decrease was reflected in the control delay. The overall intersection delay decreased by 1.5 seconds per vehicle, or about 6 percent.

Exhibit 3-40. Comparison of Pre-timed and Traffic-actuated Control with the Same Timing Plan
	Pre-timed Sub-problem 5b	Actuated Sub-problem 5c
Eastbound Through
v/c	0.83	0.83
g/c	0.68	0.68
Uniform delay	14.1	14.1
k value	0.5	0.37
Incremental delay	3.6	2.7
Control delay	17.6	16.7
Westbound Left
v/c	0.84	0.84
g/c	0.08	0.08
Uniform delay	54.4	54.4
k value	0.5	.37
Incremental delay	41.7	33.6
Control delay	96.1	88.0
Northbound Through
v/c	0.83	0.83
g/c	0.09	0.09
Uniform delay	53.9	53.9
k value	0.5	0.37
Incremental delay	21.9	16.9
Control delay	75.8	70.8
Overall intersection delay	24.5	23.0