Question

How to calculate Traffic LOS '' Level of service '' without using FFS.

I can use collected volume, and how can I do that ? and what are the information's needed ?

Answer 1

LOS is used to analyze highways by categorizing traffic flow and assigning quality levels of traffic based on performance measure like speed, density, delay etc.

Calculate Density - D = Vp/S

Vp= Flow Rate

S = Average Passenger Car Speed

Vp = V/PHP*N*Fhv*Fp

Vp = 15-minute passenger-car equivalent flow rate (pcphpl)

V = hourl y (volume (veh /hr), highest total one direction

PHF = peak hour factor

N = number of lanes in one direction

f = heavy vehicle adjustment factor CEE 320 Spring 2008

Fhv = heavy -vehicle adjustment factor

Fp = driver population adjustment factor

Does not consider

– Special lanes reserved for a particular type of vehicle ( , , g, ) HOV, truck, climbing, etc.)

– Extended bridge and tunnel segments

– Segments near a toll plaza

– Facilities with FFS 55 / 5 / < 55 mi/h or > 75 mi/h

– Demand conditions greatly in excess of capacity

– Influence of downstream blockages or queuing

– Posted speed limit Posted speed limit

– Extent of police enforcement

– Intelligent transportation system features

– Capacity

– enhancing effects of ramp metering