LAB 2 - Manual SPOT Speed Study Group 2 PDF

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HIGHWAY & TRAFFIC ENGINEERINGECG 564OPEN-ENDED LABOCT 2020 – FEB 2021TITLE OF EX PERIMENT : SPOT SPEED STUDY DATE OF EX PERIMENT : 2ND NOVEMBER 2020 GROUP : EC220 5C GROUP MEMBERS 1. FARAH AZMINA BT AZMI (2019893004) 2. MUHAMMAD IZZAT AIMAN BIN ROSLI (2019814604) 3. NOR ASY IRIN BINTI REJAL ...

Description

HIGHWAY & TRAFFIC ENGINEERING ECG 564 OPEN-ENDED LAB OCT 2020 – FEB 2021 TITLE OF EXPERIMENT

: SPOT SPEED STUDY

DATE OF EXPERIMENT

: 2ND NOVEMBER 2020

GROUP

: EC220 5C2

GROUP MEMBERS

1. FARAH AZMINA BT AZMI (2019893004) 2. MUHAMMAD IZZAT AIMAN BIN ROSLI (2019814604) 3. NOR ASYIRIN BINTI REJAL (2019660738) 4. NUR ARISHA BINTI MD ZIN (2019495666) 5. NURUL NADIA BINTI ABDUL RAHMAN (2019608112)

LECTURER

: IR. DR. SITI NURBAYA BINTI AB KARIM

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

1.0 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 hoped 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.

2.0 OBJECTIVES The objectives of the test are: a) To establish the speed distribution of a traffic stream at a specific site or called as basic speed data. b) To determine vehicle speed percentiles via speed trend analysis, which are useful in speed related decision making.

3.0 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. There are two (2) methods of conducting the spot speed study, radar gun (automatic) and stopwatch method (manual). The stopwatch method can be 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 inexpensive method for collecting speed data.

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4.0 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. 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 (freeflowing traffic) are more appropriate. 5.0 APPARATUS a. Stopwatch b. Safety Vest c. Measuring Wheel Roller d. Safety Cones

6.0 WAYS AND MEANS The procedure for spot speed study (manual) using stopwatch are as follows: a) Perform necessary preparations such as sufficient pens or pencils, stopwatch (manual) spot speed study data forms and clipboards, stopwatch, safety vests and others. b) Decide study location and selected site should be a STRAIGHT AND LEVEL road section that represents different traffic conditions. Page 2 of 8

c) Enumerators should arrive 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) Sketch the layout of the study area with the description of chosen reference points, position of observation, number of lanes and road class. e) Select two (2) reference points and label as Start and End point with 50 meters apart (Less than 100 meters for spot speed). f) Station two (2) observers at Start and End point. g) Observer at starting point will give a sign to 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) Station two (2) observers at Start and End point. i) Observer at starting point will give a sign to 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). j) The other observer (Start or/and End point) will record the plate registration number and vehicle classification of selected vehicle. k) Determine the speed of vehicles by using speed formula, Speed (km/hr) =

 ()  ()

7.0 DATA AND ANALYSIS NIL

8.0 DISCUSSION Spot speed is a speed studied on a short distance that is less than 100 meters. Spot speed can be calculated using a formula in which distance is divided with time. Spot speed study is very important in traffic engineering because it can control the traffic planning, measure roadway safety, establish the roadway design element, and others. Page 3 of 8

Based on the manual spot speed study, several data were obtained including the mean speed (v), standard deviation (SD) and the error (SE). There supposed to be a slightly different in term of results when using manual spot speed study. This may be occurred due to human error while taking the time travel of vehicles within the distance. There are a few factors affecting the speed study data such as driver factors such as age, distance, and the familiarity of the route. Besides, some drivers will slower down their vehicles when passing through that road. This is because they are concern with the safety of the students that crossed the road. Vehicle factor such as type, size, and horsepower of the vehicle. Other than that, roadway facilities, traffic volume and composition is also affecting the speed study data. Furthermore, the environmental factors also one of a vital factor that affect the speed study data such as time of the day and weather. Some of safety precautions practices are taken into consideration to obtain an accurate data. Avoid conducting the laboratory activity during peak hours as the congested traffic would affect the speed distribution data. Moreover, student shall avoid standing too close to the roadside and stay back while observing the speed to avoid accidents.

9.0 CONCLUSION In conclusion, spot speed study is used to determine the speed distribution of a traffic streams at a specific location and determine the vehicle speed percentiles using speed trend analysis. In this study, the data for manual method is tabulated to determine the arithmetic mean speed (v), median and standard deviation. The conclusion obtained based on the tabulated data is the highest frequency of speed.

The data is then transferred into a frequency distribution graph in order to determine the speed at 15th, 85th and 95th percentile. From the speed at 15th percentile, it can also be called as disturbance speed where the driver indicates slowness when approaching congestion situation. Meanwhile, the speed at 85th percentile gives the speed limit of the study location. Moreover, the 95th percentile is known as the design speed. Design speed is the maximum safe speed that Page 4 of 8

can be maintained over a specified time, the speed determined for geometric design is related to the physical features of a highway that might influence vehicle operation. The determination of 15th, 85th and 98th percentile will enable students to establish the effectiveness of new or existing speed limits for enforcement practices. Apart from that, speed trends also can be established to access the effectiveness of the policy on the speed limit and enforcement. The spot speed study can determine the high occurrence accidents locations at which speed is suspected to be the main cause. During this analysis, human error might arise hence it will affect the result. Human error can exist while taking the time travel of vehicles within the distance.

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10.0 APENDICES a. Appendices of Apparatus for Manual Spot Speed Study

Figure 1.0 Stopwatch

Figure 2.0 Vest

Figure 3.0 Measuring Wheel Roller

Figure 4.0 Safety Cones

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b. Appendices for Site Location

Figure 5.0 shows the site location of the study which is important to choose a suitable study location near a junction or speed bump.

Figure 6.0 shows the layout plan of pinned site location.

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