If Fp is given as 1, but the problem also states that 90% are local, with the remaining being through traffic and recreational traffic to a nearby park, do you use 1 or .9 as Fp? It didn't effect the LOS, but could if the volume was different. I used .9 since the statement gave evidence that a lower value could be used.
driver population factor
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John QPE
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I think you are correct in either usage.
I would use Fp = 1.00 because it was given to you in the problem statement. Always use what is given.
The problem doesn't say that 10% are recreational traffic, it says 10% are through traffic AND rec traffic. The rec traffic is what will effect LOS, not the through traffic. Since you don't have enough information to make the adjustment, I would stick with 1.00
I would use Fp = 1.00 because it was given to you in the problem statement. Always use what is given.
The problem doesn't say that 10% are recreational traffic, it says 10% are through traffic AND rec traffic. The rec traffic is what will effect LOS, not the through traffic. Since you don't have enough information to make the adjustment, I would stick with 1.00
ptatohed
Licenced to Spell
[SIZE= 16px]TRB HCM 2010 regarding Driver Population Factor, fp[/SIZE]
[SIZE= 16px] [/SIZE]
[SIZE= 16px]page 10-19:[/SIZE]
[SIZE= 16px]‘The driver population factor is normally 1.00, unless the driver population is dominated by unfamiliar users, in which case a value between 0.85 and 1.00 is assigned, on the basis of local characteristics and knowledge.’[/SIZE]
[SIZE= 16px] [/SIZE]
[SIZE= 16px] [/SIZE]
[SIZE= 16px]page 11-18:[/SIZE]
[SIZE= 16px]‘In general, the analyst should use a value of 1.00, which reflects commuters or otherwise-accustomed drivers, unless there is sufficient evidence that a lower value should be used.’[/SIZE]
[SIZE= 16px] [/SIZE]
[SIZE= 16px]page 11-21:[/SIZE]
[SIZE= 16px]Exh 11-16. [/SIZE]Required Data: Driver population factor; Default Value: 1.00
[SIZE= 16px] [/SIZE]
[SIZE= 16px]page 10-19:[/SIZE]
[SIZE= 16px]‘The driver population factor is normally 1.00, unless the driver population is dominated by unfamiliar users, in which case a value between 0.85 and 1.00 is assigned, on the basis of local characteristics and knowledge.’[/SIZE]
[SIZE= 16px] [/SIZE]
[SIZE= 16px] [/SIZE]
[SIZE= 16px]page 11-18:[/SIZE]
[SIZE= 16px]‘In general, the analyst should use a value of 1.00, which reflects commuters or otherwise-accustomed drivers, unless there is sufficient evidence that a lower value should be used.’[/SIZE]
[SIZE= 16px] [/SIZE]
[SIZE= 16px]page 11-21:[/SIZE]
[SIZE= 16px]Exh 11-16. [/SIZE]Required Data: Driver population factor; Default Value: 1.00
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