Advance traffic Camp for a student for making practical on real site. This handout explains the theory and calculation related.

1. [Date]
1
Advance Traffic Camp 6.0
Session DIS 2019
Programme :
Diploma Kejuruteraan Awam
Department:
Jabatan Kejuruteraan Awam

2. Traffic volume study means determining the number, movement and
classification of roadway vehicle at a given location or point of traffic stream.
So, it is defined as the procedure to determine mainly volume of traffic
moving on the roads at a particular section during a particular time.
Scope of traffic study General information for road conditions, users &
surrounding areas keeping record of pavement performance & maintenance.
A ranking system to prioritize maintenance needs a summary of the overall
condition of the pavements in any area of the road section. Helpful for special
design, use of materials or construction projects. A uniform rating system for
each side.
i. Geometric design
ii. Roadway traffic design
iii. Planning purpose
iv. Improvement purpose
v. Dynamic traffic management purpose
Traffic Volume Study
Scope of Traffic Volume Study
Objective of Traffic Volume Study

3. [Date]
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1) Traffic volume is the number of vehicles passing a given point during a
specified period of time. The importance of traffic volume study:
i. For traffic planning, design & research.
ii. To determine the efficiency of a traffic system.
iii. To evaluate the quality of service of a transport facility.
iv. To design roads – number of lanes & pavement thickness.
2) Volume study methods:
i. Manual Count Methods
ii. Automatic Count Methods
3) Manual Count may be used for determining:
i. Vehicle classification
ii. Turning movements
iii. Direction of travel
iv. Pedestrian movements
v. Vehicle occupancy
4) Manual Count Method:
i. Applied when small sample of data is required.
ii. For periods less than one (1) day.
iii. Normal intervals are 5, 10 or 15 minutes.
iv. Counts are not usually taken on Mondays, Fridays and weekends.
Traffic Volume Study

4. [Date]
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During the study, a few things to be considered:
Select the study location
Plan the data collection preparations
Select a time
Observation and measuring data
Collect and process the data
Evaluate the data
Calculate the speed percentiles
Finalize the report
Table 1.1: Raw Data frequency of vehicle with respect to speed range
Speed Class
(km/h)
Frequency
10-14 2
15-19 1
20-24 2
25-29 8
30-34 25
35-39 38
40-44 30
45-49 29
50-54 9
55-59 4
Total 148
Work procedure
Examples

5. [Date]
5
Speed
class
(km/h)
Upper limit
(km/h)
Class
midpoint
(km/h)
no of
observation
% of total
observation
cumulative
percentage
10.5 0 0 0
10-14 14.5 12 2 1.35 1.35
15-19 19.5 17 1 0.68 2.03
20-24 24.5 22 2 1.35 3.38
25-29 29.5 27 8 5.41 8.78
30-34 34.5 32 25 16.89 25.68
35-39 39.5 37 38 25.68 51.35
40-44 44.5 42 30 20.27 71.62
45-49 49.5 47 29 19.59 91.22
50-54 54.5 52 9 6.08 97.30
55-59 59.5 57 4 2.70 100.00
148 100.00
Table 1.2: Cumulative percentage
Graf histogram percentage of total observation versus speed, km/hr
Figure 1.1: Graph for Cumulative percentage vs Speed
15.0 20 25 30 35 40 45 50 55
observation
% of total observation vs Speed (km/h)
Solution

6. [Date]
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Graf Histogram Percentage of Total Observation versus speed, km/hr
Figure 1.2: Graph curve percentage of total observation versus speed
Graf Curve Percentage Cumulative Observation versus speed, km/hr
Figure 1.3: Graph curve percentage cumulative observation versus speed

7. [Date]
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Mean Speed
Speed class
(km/h)
class midpoint
(km/h),x
no of observation,f fx
10-14 12 2 24
15-19 17 1 17
20-24 22 2 44
25-29 27 8 216
30-34 32 25 800
35-39 37 38 1406
40-44 42 30 1260
45-49 47 29 1363
50-54 52 9 468
55-59 57 4 228
Total 148 5826
therefore, the mean
speed =
Median Speed
Table 1.3: Mean speed of data
(5826/148)
=39.36 km/h
Table 1.4: Median speed for speed data
Speed class
(km/h)
Lower limit no of observation cumulative no of observation
10-14 9.5 2 2
15-19 14.5 1 3
20-24 19.5 2 5
25-29 24.5 8 13
30-34 29.5 25 38
35-39 34.5 38 76
40-44 39.5 30 106
45-49 44.5 29 135
50-54 49.5 9 144
55-59 54.5 4 148
Total 148

8. [Date]
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therefore, the
median =34.5+ (148/2)-38 x 5 =39.24 km/h
38
Graph of P50
Figure 1.3: Graph for P50
Pace
Figure 1.4: Speed range for pace
10 15 20 25 30 35 40 45 50 55
P50=38km/h
Pace= 35-45km/h

9. [Date]
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Percentage of Pace
Figure 1.5: Cumulative % from pace
Percentage of 85
Figure 1.6: 85th
percentile
10 15 20 25 30 35 40 45 50 55
10 15 20 25 30 35 40 45 50 55
P15
P30
P85=46km/h
P95

10. [Date]
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Standard Deviation
Speed
class
(km/h)
midpoint
(km/h),x x2
No of
observation,f fx fx2
10-14 12 144 2 24 288
15-19 17 289 1 17 289
20-24 22 484 2 44 968
25-29 27 729 8 216 5832
30-34 32 1024 25 800 25600
35-39 37 1369 38 1406 52022
40-44 42 1764 30 1260 52920
45-49 47 2209 29 1363 64061
50-54 52 2704 9 468 24336
55-59 57 3249 4 228 12996
148 5826 239312
Table 1.5 :Standard Deviation
therefore,the standard
fx
2
- (fx)2
deviation = f-1 f (f-1)
239312 _ (5826)^2
148-1 148(148-1)
1560.1
=8.23 km/h
From graph:- P85 - P15
= 46-29
2 2
= 8.5 km/h
1627.9 -

11. [Date]
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Speed Study Speed is an important transportation consideration because it
relates to safety, time, comfort, convenience, and economics. Spot speed
studies are used to determine the speed distribution of a traffic stream at a
specific location. The data gathered in spot speed studies are used to determine
vehicle speed percentiles, which are useful in making many speed-related
decisions.
For peak flow analysis, speeds are measured during the peak period. For
assessing general speed trends or for setting speed limits, off-peak
measurements are more appropriate. The selection of the target vehicle that
represents the vehicle population under study is also important.
i. Determining existing traffic operations and evaluation of traffic control
devices.
ii. Establishing roadway design elements.
iii. Assessing roadway safety questions.
iv. Monitoring traffic speed trends by systematic ongoing speed studies.
v. Measuring effectiveness of traffic control devices or traffic programs,
including signs and markings, traffic operational changes, and speed
enforcement programs
Spot Speed Studies
Scope of Spot Speed Studies
Objective of Spot Speed Studies

12. [Date]
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4.0 INTERSECTION DESIGN (TRAFFIC LIGHT PHASE)
a) Table 1 below show peak hour-volumes and saturation flow for a
major intersection on an expressway
Lane group North South East West
Flow
(pcu/
hr)
Car 280 245 580 690
Motorbike 150 112 150 100
Bus 50 40 47 40
Heavy
vehicle
60 58 49 60
Saturation flow,S
(pcu/hr)
3160 3160 1970 1970
Table 4.1
Given data Assume:
Car = 1.00 pcu Amber time,a = 3 sec
Bus = 2.25 pcu Lost time,l = 2 sec
Heavy vehicle = 1.75 pcu integrated period,I
= 4 sec Motorbike = 0.33 pcu
From data given,determine:
i. optimum cycle for both phases
ii. the actual green time for each phase
iii. the time diagram for each phase

13. [Date]
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Lane group North South East West
Flow
(pcu/hr)
1
Car 280 x 1.00 245x1.00 580x1.00 690x1.00
Motorbike 150x0.33 112x0.33 150x0.33 100x0.33
Bus 50x2.25 40x2.25 47x2.25 40x2.25
Heavy
vehicle
60x1.75 58x1.75 49x1.75 60x1.75
547 473.46 821 918
Saturation flow,S (pcu/hr) 3160 3160 1970 1970
0.17 0.15 0.42 0.47
Choose y max 0.17 0.47
Total,∑ y max = 01.7 + 0.47 = 0.64 ≤ 0.85 OK
Cycle time, Co = 1.5 L + 5
1- ymax
L = N ( I-a) + N (l)
= 2 (4-3) + 2 (2)
= 6s
Co = 1.5 (6) + 5 = 38.89 s ≈ 39 s
1 - 0.64
Available green, G = Co - L
= 39 - 6
= 33 s
STEP4
STEP6

14. [Date]
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Effective green,
Phase N/S = G (a) = y (N/S) x G
∑ y max
= 0.17 x 33
0.64
= 8.77 s ≈ 9 s
Phase E/W = G (b) = y (E/W) x G
∑ y max
= 0.47 x 33
0.64
= 24.23 s ≈ 24 s
Actual green, g
(NS), g = G(a) + l – a
= 9 + 2 – 3
= 8s
(EW), g = G(b) + l – a
= 24 + 2 – 3
= 23s
STEP9

15. [Date]
15
Timing schedule
N/S
Co=39s
E/W
8s 3s 28s
Green Amber