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Problem 3: Shenendehowa Campus. To examine (1) PHF, (2) heavy vehicles & (3) impact dilution. 3a: AM & PM Peak Hour - Existing Conditions 3b: PM Peak Hour - With Conditions. Characteristics of Moe Road Intersection Signalized & fully actuated 2 lanes EB (left-through & exclusive right)
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Problem 3: Shenendehowa Campus To examine (1) PHF, (2) heavy vehicles & (3) impact dilution. • 3a: AM & PM Peak Hour - Existing Conditions • 3b: PM Peak Hour - With Conditions
Characteristics of Moe Road Intersection • Signalized & fully actuated • 2 lanes EB (left-through & exclusive right) • 2 lanes WB (left & through-right) • 2 lanes NB (left & through-right) • 1 lane SB (left-through-right)
The volumes to/from the north are extremely small because a church is the only building generating traffic on that approach • Traffic leaving the Shenendehowa campus uses the NB left and right Arrival Patterns • Large volumes exist on the EB, WB and NB approaches
Sub-problem 3a: Shenendehowa Campus AM & PM peak - Existing Conditions What does the PHF account for? We will use the highly peaked flows at the entrance to the Shenendehowa campus to show how the peak hour factor works and the effects it has. Variations in flows that occur during the heaviest hour of traffic When you input the hourly volumes and the peak hour factor, you will evaluate the conditions that exist during the peak 15 minutes, the time when the facility is most heavily loaded.
When is the AM peak hour? What other observations should be made? Doing a standard peak hour analysis we get a LOS = C High variability
What other observations should be made? When is the PM peak hour? - Not as much variability as the AM peak - Less EB rights & WB lefts than in the AM peak - Major increase in % of heavy vehicles, relative to AM peak, on some approaches
Comparison of delays & LOS for the AM & PM peaks What observations can be made? Questions to consider: - Are either of the conditions shown in this table likely to occur? - Are these good representations of the conditions in either peak hour? - Are they pessimistic? Optimistic? - Similar LOS - There is less delay in the PM Peak
How would the results change if only the peak 15 minute period was considered? How does the delay change between base case and by-movement? The by-movement delay is highly over estimated based on the data collected for each 15 minute time period
How would the results change if only the peak 15 minute period was looked at? Is there consistency between the original peak hour analyses and each of the 15-minute interval analyses? No, there are significant differences
Effects of Heavy Vehicles What would happen if the heavy vehicle percentages were ignored? The result would be a significant decrease in delay, but of course the intersection would not be accurately evaluated
Sub-problem 3b: Shenendehowa Campus PM peak - With Conditions What would the effects be at this intersection if the traffic at Maxwell Drive were increased? The sensitivity analysis suggests the changes in overall delay are quite small
What have we learned? • We’ve seen that you have to be careful in using the peak hour factor. • It’s good to incorporate a PHF so that the conditions in the peak 15 minutes are examined. But unless you know the flows all peak simultaneously, it’s not good to use peak hour factor values that are movement specific. • We’ve also seen that it is important to pay attention to the heavy vehicle percentages. • We’ve seen that there are ways to check for impacts from site-generated traffic.