Evaluation of level of service. Level of service (LOS) is a qualitative measure used to relate the quality of traffic service. LOS is used to analyze highways by categorizing traffic flow and assigning quality levels of traffic based on performance measure like speed, density,etc.

1. EVALUATION OF LEVEL OF
SERVICE at Chatikara, Mathura
SHASHANK KAMAL
SAURABH MITTAL

2. BACKGROUND OF THE STUDY
 Traffic congestion is one of many serious global problems of
both developed and developing countries.
 It poses severe threat to economy as well as the environment.
 Results in high operation cost.
 Loss of time, high delay, high travel time.
 Increase in fuel consumption.

3. OBJECTIVE OF THE STUDY
 To assess the causes of traffic congestion
 To evaluate the level of service(LOS) and performance of the
intersections
 To estimate the cost of traffic congestion at the intersection
 To assess the relationship of traffic congestion and traffic
accident
 To suggest some possible solution to the congestion.

4. TRAFFIC CONGESTION AND IT’S
SOURCES
 Congestion is travel time or delay in excess of that normally incurred
under light or free flow travel condition.
 Unacceptable congestion is travel time or delay in excess of an agreed
upon norm.
Figure 1.1

5. Contd.
1. Too much traffic for the available physical capacity to handle:
 Bottlenecks
2. Traffic-influencing events:
 Traffic Incidents Such As Crashes And Vehicle Breakdowns;
 Work Zones;
 Bad Weather;
 Special Events; And
 Poorly Timed Traffic Signals.

6. CONCEPT OF LEVEL OF SERVICE
 The LOS concept is use for highways in an era of rapid expansion in the use and
availability of the private motor car.
 The primary concern is congestion, and it is commonly held that only the rapid
expansion of the freeway network would keep congestion in check.
 LOS can also be applied to surface streets, to describe major signalized
intersections.
 A crowded four-way intersection where the major traffic movements were
conflicting turns might have an LOS D or E.
 At intersections, queuing time can be used as a rubric to measure LOS; computer
models given the full movement data can spit out a good estimate of LOS.
 Level of service (LOS) is a qualitative measure used to relate the quality of traffic
service. LOS is used to analyze highways by categorizing traffic flow and assigning
quality levels of traffic based on performance measure like speed, density ,etc.

7. Contd.
LOS-A: It represents free-flow condition of roadway which is not
possible to design.
LOS-B: It represents design condition of roadway on a stable exits.
It is 70% of VSF.

8. Contd.
 LOS-C: It represents still stable -flow exits. It is 50% of VSF.
 LOS-D: In this traffic flow is tending toward unstable flow.
Avg. speed is 40% of VSF.
 LOS-E: It represents breakdown condition of roadways. Avg.
speed 33% of VSF.
 LOS-F: It is worst condition of roadways. Always jamming like
situation is created. Avg. speed is 25% of VSF.

9. Level of Service E Level of Service F

10. METHODS
 PCU (Passenger Car Unit): Different types of vehicles in a traffic stream have
different characteristics like width, length and height and sometimes they produce
inconvenience for other vehicles, so for expressing highway capacity a unit is used
called passenger car unit.
 PCU=hi/hc
Where: PCU=passenger car unit
hi= headway of i-th vehicle
hc= headway of passenger car

11. Contd.
 Passenger Car Unit Analysis
 Passenger car unit analysis is important because it considers different
characteristics like width, length and height that cause serious variations in the
traffic stream.
 Due to this difference each type of vehicle has distinct effect on the traffic steam.
Therefore the PCU is important because it compare the effect of different vehicle
with respect to single car.
 Using headway method analysis was made to compute PCU.
PCU factor results:

12. Example:

13. Methodology used in LOS
 Traffic Simulation Model:
Simulation modelling is an increasingly popular and effective tool for analyzing a wide
variety of dynamical problems those associated with complex processes which cannot
readily be described in analytical terms
 Need Of simulation:
 1. When mathematical or analytical treatment of a problem is found infeasible or
inadequate due to its complex nature.
 2. When there is some doubt in the mathematical formulation or results.
 3. When there is a need of an animated view of flow of vehicles to study their
behavior.

14. Flow diagram of a Microscopic traffic simulation
model

15. Simulation Package
 Now a days, traffic simulation packages like CORSIM and
VISSIM are frequently used as tools
 for analyzing traffic. VISSIM is a microscopic, time step and
behaviour based simulation model
 developed to analyze the full range of functionally classified
roadways and public transportation operations.

16. PTV VISSIM
 PTV Vissim is a microscopic multi-modal traffic flow simulation software package
developed by PTV Planung Transport Verkehr AG in Karlsruhe, Germany. The name
is derived from "Verkehr In Städten - SIMulationsmodell" (German for "Traffic in
cities - simulation model"). PTV Vissim was first developed in 1992 and is today a
global market leader.
 PTV Vissim is part of the PTV Vision Traffic Suite which also includes PTV Visum
(traffic analysis and forecasting) and PTV Vistro (signal optimisation and traffic
impact).