UiTM Spot Speed Study Lab Report PDF

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HIGHWAY AND TRAFFIC ENGINEERINGECGOPEN-ENDED LABSEMESTER 6TITLE OF EXPERIMENT : SPOT SPEED STUDYDATE OF EXPERIMENT : 15 APRIL 2021GROUP : 6A6A (GROUP 3)GROUP MEMBERS 1. NURUL IZZATY BT ADNAN (2018297786)2. NURUL SYAMIMI BT MOHAMAD REDZUAN(2018436006)3. NURIN AQILAH BT MOKHTAR (2018439736)4. NURUL LI...

Description

HIGHWAY AND TRAFFIC ENGINEERING ECG564 OPEN-ENDED LAB SEMESTER 6 TITLE OF EXPERIMENT

: SPOT SPEED STUDY

DATE OF EXPERIMENT

: 15 APRIL 2021

GROUP

: 6A6A (GROUP 3)

GROUP MEMBERS

1. NURUL IZZATY BT ADNAN (2018297786) 2. NURUL SYAMIMI BT MOHAMAD REDZUAN (2018436006) 3. NURIN AQILAH BT MOKHTAR (2018439736) 4. NURUL LIWANI BT MD ZAIN (2018248882) 5. MUHAMMAD ZULHILMI BIN MUHAMMAD ZULHAZLI (2019528147)

LECTURER

: DR. MUHAMMAD AKRAM BIN ADNAN

LEVEL OF OPENESS

:

1

MARKS

COMMENTS

INTRODUCTION BASIC CONCEPTS METHODOLOGY RESULTS & ANALYSIS

1

2

3

4

5

DISCUSSION

1

2

3

4

5

CONCLUSION

1

2

3

4

5

TOTAL MARKS

TABLE OF CONTENTS

Page 1.1

Introduction …………………………………………………………….

3

1.2

Objective ………………………………………………………………..

3

1.3

Theoretical Background ……………………………………………….

3

2.1

Problem Statement ……………………………………………………..

4

3.1

Procedure …………………………………………………….................

5

4.1

Results …………………………………………………………………..

8

4.2

Discussion ………………………………………………………………

15

4.3

Conclusion ………………………………………………………………

17

REFERENCES

1.1

INTRODUCTION Level 1 laboratory activity refers to condition where the problem and ways & means are guided and given to the students. However, the answers to the assignment are left to the students to solve using the group creativity and innovativeness. The activity is hope to slowly introduce and inculcate independent learning amongst students and prepare them for a much harder task of open ended laboratory activities. In this laboratory activity, students are required to conduct a spot speed study (using radar gun & manual determination), by recording the speeds of sample of vehicles at a specified location in order to estimate the distribution of speeds of vehicles. Students are encouraged to develop their critical analysis skills by analyzing and presenting the experimental results appropriately.

1.2

OBJECTIVES The objectives of the test are: i.

To establish the speed distribution of a traffic stream at a specific site or called as basic speed data.

ii.

To determine vehicle speed percentiles via speed trend analysis, which are useful in speed related decision making.

1.3

THEORETICAL BACKGROUND Spot speeds are the vehicle speeds taken at a specified point along the roadway and the average of such speeds is referred to as time mean speed. A spot study is carried out by recording the speeds sample of vehicles at specified location in order to estimate the distribution of speed of vehicles. Spot speed data have a number of safety applications, including determine speed trends by systematic continuous speed studies, the measurement of traffic control devices’ or traffic programs’ effectiveness, the evaluation of speeding problems, assessing speed as a causal factor to crashes, investigate existing parameters in respect to traffic operation and control like speed limit, speed zones and the limits of no-passing zones, establish and/or evaluate the roadway’s geometric design for example sight distance elements and so forth. 3

Depending on the use of data, the observer must consider whether to collect speeds of all vehicles, including platooned vehicles or only the speeds of unimpeded vehicles. It is impossible to obtain a radar measurement for every vehicle under heavy traffic conditions. One may collect all speeds during the peak period for peak flow analysis whereas the speed of unimpeded vehicle would be collected for assessing general speed trends or for setting speed limits or assessing the impact of speed zone signing, thereby off-peak measurement (free-flowing traffic) are more appropriate. Study duration of one hour or a sample size of at least 100 vehicles. The radar gun is position according to procedure specified in the user manual.

2.1

PROBLEM STATEMENT Over speeding is one of the major causes of road accidents in Malaysia. Speed limits are implemented to prevent over speeding of vehicles. To determine whether the drivers of vehicles comply with the speed limit, spot speed studies are carried out to determine the speed of vehicles operating on the road.

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3.1

PROCEDURE There are two (2) methods of conducting the spot speed study, radar gun (automatic) and stopwatch method (manual). The stopwatch method is used to successfully complete a spot speed study using a small sample size taken over a relatively short period of time. The stopwatch method is a quick and in expensive method for collecting speed data.

i.

The procedure for spot speed study using radar gun are as follows:

a) Necessary preparations are performed such as sufficient pens or pencils, radarmeter spot speed study data forms and clipboards, radar speed meters are in good condition, read instructions and procedure for the used radar gun, obtain backup battery, safety vests and others.

b) Study location is decided and the selected site is a straight and level road section that represents different traffic conditions.

c) Enumerators are arrived 30 minutes earlier at site in order to familiarize (do visual appraisal survey) with it prior to select strategic location, distribute the equipment, fill in the general information of the spot speed data recording forms that comprise the observer’s name, time and date of study, name of site, posted speed limit and weather condition and begin at the planned time.

d) The layout of the study area is sketched with the description of chosen reference points, position of observation, number of lanes and road class.

e) The enumerators, the radar unit and the station for speed data collection are inconspicuous where possible so that vehicular speeds are significantly not effected by the data collection activities.

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f) The samples are randomly selected, for example the observer is recorded a speed reading for every third vehicle or every fifth vehicle. g) The radar meter is directed a line with on coming traffic as possible, meaning to make it as close to the roadway as possible (an exception when the vehicles selected and radar unit tends to affect vehicle speeds considerably).

h) The vehicle speeds area observed for duration of one-hour study or 100 samples.

ii.

The procedure for spot speed study (manual) using stopwatch are as follows:

a) Necessary preparations are performed such as sufficient pens or pencils, stopwatch (manual) spot speed study data forms and clipboards, stopwatch, safety vests and others.

b) Study location is decided and the selected site is a straight and level road section that represents different traffic conditions.

c) Enumerators are arrived 30 minutes earlier at site in order to familiarize (do visual appraisal survey) with it prior to select strategic location, distribute the equipment, fill in the general information of the spot speed data recording forms that comprise the observer’s name, time and date of study, name of site, posted speed limit and weather condition and begin at the planned time.

d) The layout of the study area is sketched with the description of chosen reference points, position of observation, number of lanes and road class.

6

e) Two (2) reference points are selected and labeled as Start and End point with a distance of 50 metre apart (less than 100 metre for spot speed).

f) Station two (2) observers at Start and End point. g) A sign is given by the observer at starting point to the observer at end point to record the vehicle’s time travel from start to end point (Make sure both observers are use the same vehicle’s body reference point).

h) The plate registration number and vehicle classification of selected vehicle are recorded by the other observer (Start or/and End point).

i) The speed of vehicles are determined by using speed formula, speed = distance/time (km/hr).

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4.1

RESULT AND ANALYSIS

Number of Vehicles

Speed (km/h)

Number of Vehicles

Speed (km/h)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

64 68 58 48 76 84 80 77 45 53 80 79 84 80 79 79 77 61 82 69 74 68 64 72 82

26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

79 71 66 72 77 68 71 50 64 74 84 55 63 77 77 84 60 43 98 79 76 77 82 76 64

Table 1: Raw data (group 3)

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Number of Vehicles

Speed (km/h)

Number of Vehicles

Speed (km/h)

76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100

80 64 82 63 56 48 66 50 56 61 60 60 56 63 72 47 58 51 50 42 48 68 51 77 87

51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

69 72 71 76 74 61 45 50 50 56 68 47 68 72 19 51 69 74 77 63 68 56 60 60 60

Table 1: Raw data (group 3)

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Middle

Frequency,

Speed, U

F

(km/h)

(no of cars)

10-19

14.5

1

14.5

1

1

2683.24

20-29

24.5

0

0

0

1

0

30-39

34.5

0

0

0

1

0

40-49

44.5

9

400.5

9

10

4277.16

50-59

54.5

17

926.5

17

27

2367.08

60-69

64.5

30

1935

30

57

97.2

70-79

74.5

29

2160.5

29

86

1949.96

80-89

84.5

13

1098.5

13

99

4306.12

90-99

94.5

1

94.5

1

100

795.24

100

6630

Speed (km/h)

TOTAL

Percentage F*U

Frequency (%)

Cumulative Frequency (%)

Table 2: Calculated relative and cumulative frequencies

Figure 1: Frequency histogram graph

10

F(U-Ub)2

16476

Figure 2: Frequency distribution graph

Figure 3: Cumulative frequency graph

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Figure 4: Cumulative frequency of speed

12

CALCULATION 1. Arithmetic Mean Speed, Ub =

=

𝐹𝑈 𝐹

6630 100

= 66.3

2. Median Speed From graph Figure 3, P50 = 62.5 km/h

3. Modal Speed From the Histogram in Figure 1, the Modal Speed is at range 60 – 69 km/h with the number of frequencies of 30 vehicles.

4. Standard Deviation S=√

∑ 𝑓(𝑈−𝑈𝑏)2 𝑁−1

S=√

16476

100−1

= ± 12.90 5. Standard Error D= D=

𝑆

𝑁

12.90 100

= 0.129

Adequacy of data for 95 % confident significant level 95%

mean + 1.96 D = 66.3 + 1.96 (0.129) = 66.05 to 66.55

13

6. From Graph, Based on Figure 3, P15 = 47.5 km/h P85 = 74.0 km/h P98 = 83.0 km/h Therefore, Modal speed = 64.5 km/h Disturbance speed, P15 = 47.5 km/h Median speed, P50 = 62.5 km/h Speed limit, P85 = 74.0 km/h Design speed, P98 = 83.0 km/h

Time Mean Speed = Total speed of vehicles/Total vehicles = 6622/100 = 66.22 km/h

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4.2

DISCUSSION This spot study have been performed by applying automatic method using radar gun to establish the speed distribution of a traffic stream and to find out the vehicle speed percentiles at a specific site. The study was conducted at Multilane Highway Puncak Perdana. This study involved 100 data of speed which all type of vehicle. Based on data that collected from study location as shown in table, the arithmetic mean speed was calculated 66.3 km/h. Based on data, the value of standard of deviation, by using formula that given is 12.90 km/h. Then the standard error is 0.129. By analyzing the histogram graph in figure 1, The modal speed is at range 60-69 km/h with the number of frequencies of 30 vehicles. Most of the vehicle in the experiments were travelling at this speed. Based on the table, the cumulative frequency graph is plotted. By analyzing the graph which is figure 3 the obstacle, the speed limit and design can be determined. Values for 50th Percentile Speed is 62.5 km/h which is median speed, 15th Percentile Speed is 47.5 km/h which is within 60km/h which can be called disturbance speed. While 85th Percentile Speed is 74 km/h commonly utilized to determine the speed limit and 98th Percentile Speed is 83 km/h which is within 100 km/h that were read directly from cumulative frequency graph in Figure 3. And based on that, the speed limit the road is 74 km/h. next for the design speed for the highway is 83 km/h. Compare to manual cumulative frequency graph that have been plotted, there is slightly difference for value 50th Percentile Speed which is 62.5 km/h and 98th Percentile Speed which is 83.5 km/h , 15th Percentile Speed is 47 km/h and the rest are the same. For this case, the are several cars that seem speed over the speed limit. There are cause by a few factors that can be influence such as the road itself give the access for drive fast. Since the lane is straight then there are less traffic lights and the warning sign so there is nothing to slow down the speed. furthermore, the way of pavement there is still in good condition without any distress or deformation so there are no problem will be occurred when drive so fast. There are several factors that affect the spot study at the location stated. First, traffic congestion can affect the data especially during peak hour which causing the vehicles slow down. Second, the drivers may notice someone taking the speed reading. The

15

distraction may have caused drivers to change their speed, resulting in an inaccurate recorded speed value. Cars that changing lane travelled extra distances and were therefore timed of recording, so the lane changing cars were recorded at slower speed than they were actually travelling. Next, the vehicle type. For example, the vehicle with larger build and heavy like lorry tends to move slower than a small build and lightweight vehicle like motorcycle. The error that occurs during data is collected may because the radar gun is not in good condition as the device was being used for a certain period so, the device should check properly before using it.to ensure the accuracy of the data.

16

4.3

CONCLUSION The purpose of this experiment is to determine whether the drivers of vehicles comply with the speed limit, therefore spot speed study is carried out to determine the speed of vehicles operating on the road. The study involved 100 number of vehicles on the road. Hence, the experiment was conducted at a specific site which is at Multilane Highway Puncak Perdana and the data was collected. The objectives of this experiment are to determine vehicle speed percentiles via speed trend analysis. The data from the study was observed and used to calculate the values of arithmetic mean speed, median speed, modal speed, standard deviation, standard error and percentiles. These values can be obtained from the data tabulated in the Table 2 and graphs in Figure 1, Figure 2 and Figure 3. From this study, the data was tabulated in the form of three graphs which were frequency histogram graph, percentage frequencies of speeds graph and cumulative frequencies of speeds graph. Next, the arithmetic mean speed is 66.3 and median speed is 62.5 km/h. While, standard deviation and standard error obtained are 12.90 and 0.129. Besides, the adequacy of data for 95 % confident significant level is from 66.05 to 66.55. The modal speed is 64.5km/h. From the graph in Figure 3, the median speed, P 50 is 62.5 km/h and disturbance speed is, P 15 is 47.5 km/h. Also, the speed limit, P85 is 74.0 km/h and design speed, P 98 obtained is 83.0 km/h. Finally, the time mean speed calculated from this study is 66.22 km/h. To sum up the spot speed study, we obtained the highest speed between 60 km/hr to 69 km/hr with 30 of 100 vehicles. The average speed of this study is 66.3 km/hr. The study was conducted at Multilane Highway Puncak Perdana and the speed limit available there is 80 km/h and it is near to the value of 85th percentile of 74 km/h that we obtained. The design speed is 83 km/h which also suit the available speed limit. After determining the spot speed, we conclude that the speed limit is suitable and drivers drive below speed limit. This shows the effectiveness of the speed enforcement in the area. We can also conclude that the speed trend analysis is precisely obtained as the difference between excel plotted cumulative graph and manually plotted cumulative graph is almost the same.

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REFERENCES

1. Google Street View of B49 Persiaran Mokhtar Dahari. Retrieved from https://www.google.com/maps/place/UiTM+Puncak+Perdana+Campus/@3.1290138, 101.5082188,3a,18.2y,79.16h,86.19t/data=!3m9!1e1!3m7!1s7kUGb2Esas0CU7hoCU o7VA!2e0!7i16384!8i8192!9m2!1b1!2i51!4m5!3m4!1s0x31cc51962c5fb867:0x908f e72ee248f8fa!8m2!3d3.13366!4d101.493738

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