Computation of Speed, Density, and Level of Service For An Extended Section of Freeway

[owillis28]

Determine the LOS on a regular weekday on a 0.40-mi section of a six-lane freeway with a grade of 2 percent, using the following data:

Hourly Volume, v= 3000 veh/h

PHF= 0.85

Traffic Composition:

Trucks= 12%

RV's= 2%

Lane Width= 11 ft

Terrain= level

Base free-flow speed= 70 mph

Shoulder width= 6 ft

Interchange spacing = 1 mile

Driver population adjustment factor fp= 1

Good Luck!!

owillis

 

[cement]

looks like a good 6 min exam type question. too bad I loaned out all my books! ldman:

 

[Suns Den]

Determine the LOS on a regular weekday on a 0.40-mi section of a six-lane freeway with a grade of 2 percent, using the following data:
Hourly Volume, v= 3000 veh/h

PHF= 0.85

Traffic Composition:

Trucks= 12%

RV's= 2%

Lane Width= 11 ft

Terrain= level

Base free-flow speed= 70 mph

Shoulder width= 6 ft

Interchange spacing = 1 mile

Driver population adjustment factor fp= 1

Good Luck!!

owillis

FFS = 70 MPH - 1.9 -0.0-0.0-0.0

= 68.1

FLOW RATE VP = 3000/0.85*6*.9363*1 = 629.4 PC/H/LN

FHV = 1/(1+0-14(1.5-1)) = 0.9346

DENSITY D = 629.4/68.1 = 9.242

FROM EX-23-3 -> LOS A

 

[owillis28]

Solution to my previous posted example problem.

Suns Den - Remember that in the formula for flow rate in passenger cars per hour per lane that the number of drive lanes (N) is in one direction. I think that is where you made your error

 

[Suns Den]

Solution to my previous posted example problem.
Suns Den - Remember that in the formula for flow rate in passenger cars per hour per lane that the number of drive lanes (N) is in one direction. I think that is where you made your error

So whaz the right assumption when it is not clear/given if the lanes are one way or two way...