Spot Speed Study

INTRODUCTIONSpeed is the rate of movement of a vehicle, generally expressed in kilometers per hour. A spot speed study is a study of traffic speed at one point or spot on a traffic way. It consists of a series or a sample of observations of the individual speeds at which vehicles are approaching an intersection or passing a point at a non-intersection location. These observations are used to estimate the speed distribution of the entire traffic stream at that location, under the conditions prevailing at the time of the study.Spot speed studies can be used to study speeds at problem locations in order to determine whether speeds are too high and if complaints received are justified, for accident analysis in order to determine the relationship of speed to accidents which may help in developing corrective measures, and for before-and-after studies in order to evaluate the effect of some change in controls or conditions.In relation with this study, there have been several complaints of vehicles speeding along the UTHM-Fujitsu section of road. This poses a danger to motorists, pedestrians and cyclists as there is a lot of activity in the area. Furthermore, there are plenty of right-turning movements along this stretch of road, with no storage lanes provided for right-turners. This is dangerous because the right-turners stop on the fast lane and have no protection.

OBJECTIVEThe objectives of this study are:

1. To determine the speed characteristics of traffic at the location.2. To justify the problem of speeding at the location.

APPARATUS1. Radar Gun2. Forms SS1 and SS23. Graph Paper (3 nos)4. Safety Vest

PROCEDURE1. The spot at which the speed data will be collected are being identified.2. The radar gun that being used are needed to measured the speed of vehicles

according to their respective vehicle class – Class 1 (Motorcycles), Class 2 (Cars), Class 3 (Vans & Medium Trucks), and Class 4 (Large Trucks & Buses).Make sure that the operator of the radar gun is not seen by the motorists

3. All speed measurements are recorded in Form SS1.4. Based on Form SS1, the mean, maximum and minimum speed of vehicles is

being determined according to their class. All the findings are being commented.

5. The data in Form SS1 are being transferred to Form SS2.6. The following data are being plotted:

(a) Frequency Histogram (Percentage of vehicles vs. Speed)

(b) Frequency Distribution Curve (Percentage of vehicles vs. Speed)(c) Cumulative Frequency Distribution Curve (Cumulative percentage vs. Speed)

7. The following speed characteristics are being determined:(a) Mean speed(b) Median speed(c) Mode speed(d) 85-th Percentile speed(e) Standard deviation(f) Pace

8. All the findings are being stimulated.

DATA ANALYSIS AND RESULT

Form SS1Location: In front Factory Fujitzu Date : 16-2-2009 Time 2.35pm - 3.35pm Weather: Sunshine

TimeSpot Speed (km/h)

Vehicle Class1 2 3 4

2.35pm until

2.45pm

56 62 65 66 55 44 70 64 52 53 65 5968 36 45 76 70 63 58 75 74 64 78 5575 57 50 63 55 63 72 48 53 53 5654 62 66 57 69 56

62 42 4646 46 7564 72 6672 65 7548 77 8866

2.45pm until

2.55pm

44 37 80 70 45 58 52 61 56 64 55 5263 51 72 57 61 70 56 43 77 51 63 5374 55 47 60 34 88 70 57 57 54 67 6044 63 67 45 65 65 41 50 4758 62 61 63 65 87 5731 74 78 70 60 66

55 68 5177 67 5858 68 70107 57 5961 58

2.55pm until

3.05pm

75 63 72 74 74 61 61 68 67 45 71 6241 54 69 66 67 50 57 64 50 54 61 6543 43 65 59 57 69 55 59 66 60 60 5943 57 49 65 43 53 66 43 66 5735 44 60 55 51 66 63 59 6067 52 68 50 73 73 53 6258 64 46 64 78 64

59 75 6364 70 5764 72 7462 65 68

TimeSpot Speed (km/h)

Vehicle Class1 2 3 4

2.55pm until

3.05pm

65 63 6267 62 4856 57 56

3.05pm until

3.15pm

47 60 54 100 69 63 70 47 52 56 58 6661 70 73 62 67 57 43 49 65 6972 62 66 59 67 76 69 47 5768 70 60 62 70 71 56 5638 60 65 45 85 6662 67 78 65 50 6047 62 60 56 71 66

65 61 5960 67 6665 64 59

3.15pm until

3.25pm

48 58 44 42 52 80 62 55 53 61 43 4952 57 53 92 98 61 43 52 60 49 35 4786 58 61 67 63 66 38 55 58 59 56 6152 65 68 81 61 72 56 40 55 48 63 4350 56 65 62 57 77 52 62 61 8052 63 67 84 80 50 4282 60 65 49 51 6149

3.25pm until

3.35pm

67 63 61 69 65 76 60 50 53 54 53 6867 65 58 67 59 59 45 70 64 59 80 5560 63 70 66 62 70 50 60 54 5087 73 56 72 60 73 68 50 5170 54 64 69 57 60 70 57 5370 71 59 77 55 61 64 77 4550 59 99 67 60 51 50 64 5360 54 67 85

67 73 6557 73 7667 70 6350 60 6780

Form SS2Speed Class

(km/h)

Upper Limit(km/h)

Class Mid-point

(km/h)

Number of Observation

Percentage of Total

Observation (%)

Cumulative Percentage

(%)

30.5 0 0

31-35 35.5 33 4 0.88 0.88

36-40 40.5 38 5 1.10 1.98

41-45 45.5 43 27 5.96 7.94

46-50 50.5 48 35 7.73 15.67

51-55 55.5 53 60 13.25 28.92

56-60 60.5 58 89 19.65 48.57

61-65 65.5 63 84 18.54 67.11

65-70 70.5 68 76 16.78 83.89

71-75 75.5 73 32 7.06 90.95

76-80 80.5 78 23 5.08 96.03

81-85 85.5 83 7 1.55 97.55

86-90 90.5 88 4 0.88 98.46

91-95 95.5 93 1 0.22 98.68

96-100 100.5 98 5 1.10 99.78

101-105 105.5 103 0 0 99.78

106-110 110.5 108 1 0.22 100

∑ ¿453 ∑ ¿100

Calculation & Result

Speed Class

(km/h)

Class Mid-point

(km/h) (x)x2


(f)fx fx2

31-35 33 1089 4 132 435636-40 38 1444 5 190 722041-45 43 1849 27 1161 4992346-50 48 2304 35 1680 8064051-55 53 2809 60 3180 16854056-60 58 3364 89 5162 29939661-65 63 3969 84 5292 33339665-70 68 4624 76 5168 35142471-75 73 5329 32 2336 17052876-80 78 6084 23 1794 13993281-85 83 6889 7 581 4822386-90 88 7744 4 352 3097691-95 93 8649 1 93 864996-100 98 9604 5 490 48020101-105 103 10609 0 0 0106-110 108 11664 1 108 11664

∑ ¿453 ∑ ¿27719 ∑ ¿1752887

(a ) Mean Speed=∑ fx

∑ f

Mean Speed=27719453

=61.90 km /hr

(b ) Median Speed=L+[ ( n2 )−f L

f m]× C

Median Speed=60.5+[ ( 4532 )−220

84 ]×5

Median Speed=60.89 km/hr

(c ) Mode Speed = 56km/hr to 60 km/hr

(d ) 85th Percentage Speed = 68km/hr (refer to the graph Cumulative Frequency Distribution Curve)

(e ) Standart deviation ,σ=√∑ fx2

n−1−

(∑ fx )2

n (n−1 )

Standart deviation , σ=√ 1752887453−1

−(27719 )2

453 (453−1 )

Standart deviation , σ=11.21km /hr

(f) Pace = 53 km/hr to 63 km/hr (refer graph Frequency Distribution Curve)

Class 1 (Motorcycles)Speed Class

(km/h)

Class Mid-point

(km/h) (x)


(f)fx

31-35 33 2 3336-40 38 3 11441-45 43 9 38746-50 48 8 38451-55 53 12 63656-60 58 21 121861-65 63 23 144965-70 68 14 95271-75 73 10 73076-80 78 3 23481-85 83 1 8386-90 88 1 8891-95 93 0 9396-100 98 1 98

∑ ¿108 ∑ ¿6499

Mean Speed=6499108

Mean Speed=60.18 km /hrMaximum Speed = 99 km/hrMinimum Speed = 31 km/hr

Class 2 (cars)Speed Class

(km/h)

Class Mid-point

(km/h) (x)


(f)fx

31-35 33 1 3336-40 38 0 041-45 43 8 34446-50 48 12 57651-55 53 20 106056-60 58 37 214661-65 63 49 308765-70 68 39 265271-75 73 18 131476-80 78 15 117081-85 83 6 49886-90 88 3 26491-95 93 1 9396-100 98 3 294101-105 103 0 0106-110 108 1 108

∑ ¿213 ∑ ¿11199

Mean Speed=11199213


Class 3 (Vans & Trucks)Speed Class

(km/h)

Class Mid-point

(km/h) (x)


(f)fx

31-35 33 0 036-40 38 2 7641-45 43 4 17246-50 48 12 57651-55 53 18 95456-60 58 19 110261-65 63 12 75665-70 68 13 88471-75 73 3 21976-80 78 1 7881-85 83 0 086-90 88 0 091-95 93 0 096-100 98 1 98

∑ ¿85 ∑ ¿4915

Mean Speed=491585


Class 4 (Heavy Truck & Buses)Speed Class

(km/h)

Class Mid-point

(km/h) (x)


(f)fx

31-35 33 1 3336-40 38 0 041-45 43 3 12946-50 48 5 24051-55 53 10 53056-60 58 12 69661-65 63 10 63065-70 68 4 27271-75 73 1 7376-80 78 3 234

∑ ¿49 ∑ ¿2837

Mean Speed=283749


GRAPHFrequency Histogram (Percentage of Vehicles vs. Speed)

Percentage of Vehicles

Vehicle Speed km/hr0

5

10

15

20

25

30.5-35.5

35.5-40.5

40.5-45.5

45.5-50.5

50.5-55.5

55.5-60.5

60.5-65.5

65.5-70.5

70.5-75.5

75.5-80.5

80.5-85.5

85.5-90.5

90.5-95.5

95.5-100.5

100.5-105.5

105.5-110.5

Frequency Distribution Curve (Percentage of Vehicle vs. Speed)

Percentage of Vehicles

20 30 40 50 60 70 80 90 100 110 1200

5

10

15

20

25

58

6353

pace

speed km/hr

Cumulative Frequency Distribution Curve (Cumulative percentage vs. Speed)

1

20 30 40 50 60 70 80 90 100 110 1200

20

40

60

80

100

120

Cumulative Percentage

speed (km/hr)68

85

Spot Speed Study

Documents

Transcript of Spot Speed Study