Toll plaza Design and operation

1. Toll Plaza Design and
operation
Raghupathi

2. Toll Operation
• Toll tax is collected to recover the total capital outlay which
includes the
 Cost of construction
 Repairs, maintenance
 Expenses on toll operation and
 Interest on the outlay for a reasonable period of time.
• The new facility should provide reduced travel time and
increased level of service.

3. Types of Toll Collection
1. Open Toll System
• Not all patrons are charged-at the edge of the urban area
2. Closed Toll System
• Patrons pay the toll based on miles of travel and category of vehicle
• plazas are located at all the entry and exit points

4.  Methods of Toll Collection
• Manual Toll Collection
 Requires a toll collector or attendant
 Processing time is highest.
• Automatic Toll Collection
 Based on the use of Automated Coin Machine
 Accept both coins and tokens issued by the
operating agency.
• Electronic Toll Collection (ETC)
 Automatically identifies a vehicle equipped
with a valid encoded data tag or transponder
 vehicles need not stop to pay the toll.
Electronic Toll Collection (ETC)
Manual Toll Collection

5. Terminology
• Throughput: It is the number of vehicles passing through the toll plaza
over a short period of time, usually 1 hour.
• Demand: It is the sum of throughput and the number of vehicles queued
up at the toll plaza during 1 hour.
• Processing Time: It is the difference between the time a vehicle leaves
and the time when it enters the toll area. The entry time is taken from the
moment a vehicle stops in the queue.
• Queueing Area: It is the area of the toll plaza where the number of
lanes of incoming vehicles increase from the number of lanes on highway
to the number of tollbooths.

6. • Merging Area: It is the area of the toll plaza where the number of
lanes of outgoing vehicles decrease from the number of tollbooths to
the number of lanes on highway
• Optimal Toll Plaza Configuration: It is the one which minimizes
the expected time a driver must spend while travelling through the
system.
Toll Plaza Geometry

7. Merging types
At a single point (left); with rightmost lanes ending (center); in a balanced pattern (right)
Queuing area and toll booths

8. Optimum Number of Toll Booths Using Queuing
Theory
• Aim: Keeping the “Total delay time to be minimum”
Total wasted time = Queueing Delay + Merging Delay
• Queueing delay: Waiting time in the que to pay toll
• Merging delay: Waiting or slowing down to allow another vehicle in the
adjacent lane to pass
Queueing delay Merging delay

9. Assumptions
1. The traffic flow is constant in a short period.
2. The time between two cars entering the toll plaza is of
exponential distribution.
3. The traffic streams fan out into tollbooths smoothly and evenly.
4. The drivers are delayed by waiting in lines for toll collection.
5. The drivers are delayed by toll collection, and the delay is
distributed exponentially.
6. The drivers are delayed by the merging process after leaving the
tollbooths.
7. The toll plaza adopts the side merging layout at the exit.

10. Basic characteristics of queueing system:
• Arrival pattern of Vehicles
• Service pattern of servers
• Number of servers
• System capacity
• Queue discipline
 Wasted time at the tollbooth (Wa)
where,
μa = Service rate at a tollbooth (veh/hr)
Ø = Total traffic flow (veh/hr),
T = Numberof tollbooths

11.  Wasted time at merging area
• number of merging points = (T −N)
• By Little’s theorem, the average waiting time in the system tsys(λ)
• The average wasted time of a driver at a merging point is the
difference between tsys and the time he or she would spend on a
normal lane 1/μ0

12. Therefore the average wasted time of a driver
where
• μB = Service rate when merging of vehicles takes place (veh/hr)
• μ0 = Service rate when no merging of vehicles takes place (veh/hr),
• λ = Vehicle arrival rate = (k/T) × Ø (veh/hr)
• K = No. of conflicting lanes at a merging point. k has a range
between [2, T − N + 1]

13. The overall wasted time in merging (WB)
The Total Wasted Time (Wtotal) for the vehicle (Tollbooth + Merging)

14. Optimum Number of Toll Booths

15. Numerical:1
Calculate the Total delay time in toll plaza if the total no of tolls are 3 on a
single-lane highway. The total traffic flow on the highway is 800 veh/hr. Assume
the following data: Service rate of Tollbooth = 400 veh/hr; Service rate when
merging of vehicles takes place =1500 veh/hr; Service rate when no merging of
vehicles takes place =2500 veh/hr.
Solution:
Given
• N=1 lane; Ø= 800 veh/hr;
• μA = 400 veh/hr; μB = 1500 veh/hr; μ0 = 2500 veh/hr.
• Total Delay?

16. • Wasted time at tollbooth
WA = 1/(400−(800/3) )=0.0075 hr/veh = 27 sec/veh.
• Wasted time at merging area
k= ranges between [2, T-N+1]. In this case (T=3) k lies between [2,3]
• When K=2
• λ at first merging point = ( 2/3 ) × 800 = 533.3veh/hr.
• Tdiff = 1.166 sec.
• WB for the 1st merging point = ( 2/3 ) × 1.166 = 0.777sec
• When K=3
• λ at second merging point = ( 3/3 ) × 800 = 800 veh/hr
• Tdiff = 2.48 sec.
• WB for the 2st merging point =( 3/3 )×2.48 = 2.48sec.
Total WB=0.777+2.48 = 3.257 sec/veh.
Wtotal= WA+WB= 27.0 + 3.257 = 30.257 sec.

17. Numerical:2
Calculate the optimum number of tollbooths to be installed on a toll plaza,
proposed to be built on a single-lane highway. The total traffic flow on the
highway is 900 veh/hr. Assume the following data: Service rate of Tollbooth =
350 veh/hr; Service rate when merging of vehicles takes place = 1184.9 veh/hr;
and Service rate when no merging of vehicles takes place = 3017.1 veh/hr.
Solution:
Given
• N=1 lane; Ø= 900 veh/hr;
• μA = 350 veh/hr; μB = 1184.9 veh/hr; μ0 = 3017.1 veh/hr.
Determine the total vehicle delays for different values of tollbooths (T). Find
optimal from the set..!

18. • Let T=4;
• WA = 1/(350 900/4) = 0.008 hr/veh = 28.8 sec/veh.
• k ranges between [2, T −N +1] in this case (T=4) i.e. [2,4]
• at first merging point = (2/4) * 900 = 450 veh/hr.
• Tdiff=1.307 sec.
• Hence, WB = (2/4) * 1.307 + (3/4) * 3.046 + (4/4) * 8.018 = 6.176 sec.
• Wtotal = 28.8 + 6.176 = 34.976 sec.
k λ (veh/hr) Tdiff (sec) Weightage for WB
2 450 1.307 2/4
3 675 3.046 3/4
4 900 8.018 4/4
T WA WB Wtotal
4 28.8 6.176 34.976
6 18 13.839 31.839
8 15.15 16.805 31.955
10 13.846 19.815 33.661

19. Toll Plaza Capacity and Level of Service
 Capacity
• 𝑡𝑖𝑗 represents the service time in seconds for Vehicle Type i and Toll
Collection Type j
𝑡𝑖𝑗 = αt1j
• t1j = service time for an automobile (Type 1) and Toll Collection Type j,
• α = automobile equivalent at toll areas for Vehicle Type
 Two categories of vehicles: automobiles and (trucks and buses)
𝑡𝑖𝑗 = βj ti1
• ti1 = service time for Vehicle Type i and manual toll collection (Type 1)
• βj = conversion factor for Type j collection to manual toll collection

20. Therefore the capacity of a toll booth with Collection Type j is
𝑐𝑗 =
3600
𝑡1𝑗
If there are 𝑛𝑗 booths with Collection Type j, the capacity of a toll plaza would be
C = 𝑗=1
𝑗
𝑛𝑗 𝑐𝑗
= n1
3600
𝑡11
+ n2
3600
𝑡21
+ ……. +nj
3600
𝑡1𝑗
C = 𝑗=1
𝑗
𝑛𝑗
3600
𝑡1𝑗
• Capacity 𝑐𝑗 and C are both expressed in terms of passenger cars per hour
• Vehicle length and the ability to accelerate are the two major factors that affect
the service time

21.  Level of Service
• Wide range of speeds exist at tolls
• Hence ‘density’ and ‘v/c’ are considered to determine LOS
Where
A = total area in length-lanes,
A1 = area in length-lanes for convergence section,
A2 area in length-lanes for re convergence section,
n1 = number of arrival lanes,
n2 = number of booths,
n3 = number of departure lanes,
L1 = length of convergence section, aud
L2 = length of reconvergence section

22. T = average total time to travel through the toll plaza area
Q = the number of vehicles appearing within this area, flow rate
i = vehicle type, and
a and t denote vehicle types of automobiles and trucks, respectively.
Therefore the Density of a toll plaza area is

23. Based on v/c ratio and density the level of service for toll plaza areas can be
determined
Limitations
1. Geometric Condition- no ramps, curves should be near by
2. Vehicle Category – Considered only two categories of vehicles
3. Toll Collection Method – no advanced toll collecting equipment is used
LOS Density (pc/mi/ln) v/c
A <12 0.24
B <20 0.40
C <30 0.57
D <42 0.74
E <67 1.00
F >67 -

24. • Service time of a toll both:
• An imaginary reference line located 55 ft from attendant, that the
point over which the rear of a vehicle passes when the following
vehicle just stops to pay the toll.
• 12.87 to 14.88 sec for trucks
• 5.11 to 5.47 sec for automobiles.
• Capacity
• For general booth :650 to 705 pc per hour
• without a lifting barrier is between 665 and 745 pc per hour
• With a lifting barrier has a capacity of 600 pc per hour

25. Numerical 3

26. Configuration of Toll plaza
 The fee collection system shall be
• Speedy
• Efficient and
• User friendly.
Typical layout of a toll plaza
(IRC:SP:84-2014)

27. General design specifications
• Lane width = 3.2 m in general and 4.1 m
for oversize vehicles.
• Traffic islands at toll plaza: 25 m length
and 1 .9 m width
• Minimum length of islands shall be 35
m where 22.5 m on approach side.
• Transition of 1 in 20 to 1 in 10 may be
provided from four-lane section to the
widened width at Toll Plaza on either
side.
(IRC:SP:84-2014)

28. Number of Toll lanes
• guidelines generally followed
• Peak Hour Factor: Percentage of vehicles travelling during the peak
hour to the average daily traffic.
• forecast traffic for at least 5 years only tollable categories.
• If the queue becomes so long that the waiting time exceeds three
minutes then the number of tollbooths need to be increased.
Number of Semi Automatic Toll gates in each direction

29.  Traffic Signs
• The driver should be reminded of a toll plaza at least 1km ahead of
its existence. Another reminder should be given at 500m from the
plaza.
• STOP sign should be marked on the pavement at the toll lanes.
• Signs should be installed to inform the users about the toll price for
different categories of vehicles.
• Electronic signs should be installed over the toll booths to display
their operation status.

30.  Road Markings
• Comprise of the diagonals, lanes and chevron markings
Typical Layout building and Associated Facilities and Pavement markings
(IRC:SP:84-2014)

31.  Toll Pricing
• To recover the total capital outlay
• Toll should not exceed the benefits which the user receive
• Benefits
 Savings in travel time, travel cost
 Increase in comfort and convenience
• Factors Affecting Toll Rates
 Traffic Volume
 Willingness to pay
• Optimum Toll Charges
• Toll rate should be fixed in such a way that a vehicle owner should not shy
away from using the facility.
• The operator should get maximum toll revenue so that it can recover the
total outlay cost in a reasonable period.

32. Case Study : Delhi-Gurgaon Expressway
Toll Plaza
(wikipedia.org/wiki/Delhi_Gurgaon_Expressway)

33. Specifications
• Delhi-Gurgaon Expressway is a
6 to 8-lane expressway built
on NH-8
• Serving between Delhi and
Gurgaon, and to the domestic
and international airports
• Provides access to over 1
million commuters every day
• The 36-lane toll plaza at KM
24 is the largest toll plaza in
South Asia and the second
largest in the Asia
Location of toll plaza
Traffic composition

34. Configuration
• 36 LANES
• Space for CAR: 3.20 m and heavy vehicles: 4 m
• Pedestrian was 1.8 meters wide
• Sign boards for toll plaza are available for
the maximum distance of 800 meters.
Toll Charges for Delhi-Gurgaon Expressway
(http://nhai.org.in/spw/TollInformationdg.aspx)

35. Advantages
• Time saving with high level of
service
• Electronic toll collections-800 to
1000 cars can be processed by
smart tag lane in 1 hour
• Lower travelling cost
• Highest maintenance standards
and Good utilization of
resources.
• Safety for all the road users - SOS
pillars can be used for emergency
Disadvantages
• Inadequate in handling the
increasing traffic
• Far away from the natural
landscape and aesthetic quality
• Effecting neighboring road
network resulting narrow entries
and exits
• Overflowing drain water in the
vicinity of toll
• Peak hour traffic jams