INTRODUCTION:
Traffic Volume is the number of vehicles crossing a section of road per unit time at any selected period. Traffic volume is used as a quantity measure of flow, the commonly used units are vehicles per day and vehicles per hour.
OBJECTIVES & NEED OF STUDY:
One of the fundamental measures of traffic on a road is the volume of traffic using the road in a given interval of time. It is also termed as flow and it is expressed in vehicles per hour or vehicle per day. When the traffic is composed of a number of vehicles, it is the normal practice to convert the flow into equivalent Passenger-Car Unit (PCU), by using certain equivalency factors. The flow is then expressed as PCUs per hour or PCUs per day.
Knowing the flow characteristics one can easily determine whether a particular section of the road is handling traffic much above or below its capacity. If a traffic is heavy, the road suffers from congestion with consequent loss in journey speeds. lower the speeds causes ecomonicloss to the community due to time lost by the occupants of the vehicles and the higer operational cost of vehicles.Congesion also lead to traffic hazards. There for traffic volume data are require to draw up schemes for improvement of road network and also to allocate the scare economic resources most advantageously.
If a traffic flow data are available over the past number of years, the rate at which traffic flow has increased in the past can be easily determined. Extrapolating the past trend into the future ,a reasonable indication of the future rate of growth of traffic is made possible.
If a average annual flow and the length of the highway are known, the annual vehicle kms of travel can easily be computed. Road pavement design pertaining to numbers of commercial vehicles using a road. The maintenance needs of a highway is often based on the traffic using the road.
Traffic regulatory and control systems are designed on the basis of accurate vehicle floe data. The design signal and road junction are possible only if, among other things, the vehicle flow data are available.
METHODS FOR COUNTING TRAFFIC VOLUME:
(1) Mechanical counters(2) Manual counts
(1) Mechanical counters:
These may be either fixed (permanent) type or portable type. The mechanical counter can automatically record the total number of vehicles crossing a section of the road in a desired period. The working may be by the effect of impulses or stimuli caused by traffic
movement on a pneumatic hose placed across the roadway or by using any other of sensor. Traffic count is recorded by electrically operated counters and recorders capable of recording the impulses. The impulses caused by vehicles of light weight may not be enough in some cases to actuate. The main advantages of mechanical counter is that it can work throughout the day and night for the desired period, recording the total hourly volume, which may not be practicable in manual counting. The main drawback of the mechanical counter is that it is not possible to get the traffic volumes of various classes of traffic in the steram and the details of turning movements.
(2)Manual counts:
This method employs a field team to record traffic volume on the prescribed record sheets. By this method it is possible to obtain data which can not be collected by mechanical counters, such as vehicle classification, turning movements and counts where the loading condition or number of occupants are required. But it is not practicable to have manual count for all the 24 hours of the day .Hence it is necessary to resort to statically sampling techniques in order to cut down the manual hours involved in talking complete counts, First the fluctuation of traffic volume during the hours of day and the daily variations are observed. Then by selecting typical short count period, the traffic volume study is made by manual counting. Then by statistical analysis the peak hourly traffic volumes as well as the average daily traffic volumes are calculated. This method is very commonly adopted due to the specific advantages over other methods.
PRESENTATION OF TRAFFIC VOLUME DATA:
The data collected during the traffic volume studies are sorted out and are presented in any of the following forms depending upon the requirements.
(a) Annual average daily traffic (AADT or ADT) of the total traffic as well as classified traffic are calculated. This helps in deciding the relative importance of a route and in phasing the road development programme. In order to convert the different vehicle classes to one class such as passenger car, conversion factors known as passenger Car units(PCU) are used.
(b) Trend charts showing volume trends over period of years are prepared. These data are useful for planning future expansion, design and regulation.
(c) Variation charts showing hourly, daily and seasonal variations are also prepared .These help in deciding the facilities and regulation needed during peak traffic periods.
(d) Traffic flow maps along the routes,(the thickness of the lines representing the traffic volume to any desired scales),are drawn. These helps to find the traffic volume distribution at a glance.
(e)Volume flow diagram at intersection at either drawn to a certain scale or indicating traffic volume . Thus showing the detais of crossing and turning traffic.These data are needed for intersection design.
(f) Thirties highest hourly volume or the design hourly volume is found from the plot between hourly volume and the number of hours in an year that the traffic volume is exceeded.The 30th highest hourly volume is the hourly volume that will be exceeded
only 29 times in a year and all other hourly volumes of the year will be lessthan this volume.the annual average hourly volume (AAHV) FOUND FROM aadt will not be sufficient during considerable perioad of an year.The high facilities designed with capacity for 30th highest hourly traffic volume in the assumed year is found to be
satisfactory from both facility and economic considerations.There will be congestion only during 29 hours in the year.thus the thirtieth highest hourly volume is generally taken as the hourly volume for design.Thus the thirtieth highest houly volume is generally taken as the houly volume for design.The design hourly volume thus arrived at need not necessarily be the thirtieth highest hourly volume in all cases.
CASE STUDY OF TRAFFIC VOLUME SURVEY:
Traffic Volume study was carried out at kamrej Junction by Surat Urban Development Authority. The survey was carried out by Civil Engineering Department of SVNIT on August 20-21, 2010.
The following steps ware performed for traffic volume study: (1)Preparation of site layout
(2)Vehicle Count Survey
(3)Traffic Volume Survey Analysis
• Analysis of Traffic Volume Composition
• Hourly Variation of Traffic Volume in Vehicle/hr and PCU/hr(MODE WISE) • Hourly Variation of Traffic Volume in Vehicle/hr and PCU/hr(DIRECTION
WISE)
(2)Vehicle Count Survey: Volume Count data is as following:
Hourly Variation of Traffic Volume in Vehicle/hr (Mode wise) onDate:20/08/2010 at Kamrej Char Rasta Junction
Time Cycl e Cart Wheelere 2-s 3-Wheelere s Other s Wheelere 4-s LCV Bus Truc k Total Veh./h r 8:00 to 9:00 33 8 1018 327 28 503 183 77 103 2280 9:00 to 10:00 19 4 1436 459 16 857 192 67 121 3171 10:00 to 11:00 14 2 1439 524 140 832 202 56 120 3329 11:00 to 12:00 33 1 1850 576 4 1002 180 59 130 3835 12:00 to 13:00 26 3 1503 443 7 850 198 38 165 3233 13:00 to 14:00 26 0 194 302 28 803 208 66 139 2766 14:00 to 15:00 65 17 1134 297 14 806 224 88 134 2779 15:00 to 16:00 24 14 1205 318 8 810 202 152 145 2878 16:00 to 17:00 76 23 2320 657 259 1114 299 68 166 4982 17:00 to 18:00 119 13 3309 715 22 1135 201 82 124 5720 18:00 to 19:00 131 5 3284 623 19 1197 190 92 123 5664 19:00 to 20:00 121 13 2792 460 15 963 198 71 91 4724 20:00 to 21:00 69 8 2235 335 24 721 115 85 65 3657 21:00 to 22:00 27 7 1232 219 10 504 89 59 68 2215 22:00 to 23:00 6 1 644 119 8 300 64 91 44 1277 23:00 to 24:00 2 2 286 55 0 241 38 118 47 789 24:00 to 1:00 1 5 156 39 0 158 21 73 83 536
1:00 to 2:00 0 1 37 14 0 108 15 31 68 274 2:00 to 3:00 2:00 0 0 29 13 0 79 13 31 45 210 3:00 to 4:00 0 2 22 11 0 79 29 41 57 241 4:00 to 5:00 1 8 57 35 2 74 39 81 57 354 5:00 to 6:00 11 12 132 75 7 171 36 99 53 596 6:00 to 7:00 91 10 361 255 1 312 47 117 80 1274 7:00 to 8:00 42 39 642 293 17 347 49 101 55 1585 Total 937 198 28317 7164 629 13966 3032 1843 2283 58369 % 1.61 0.34 48.51 12.27 1.08 23.93 5.19 3.16 3.91 100
Hourly Variation of Traffic Volume in PCU/hr (Mode wise) onDate:20/08/2010 at Kamrej Char Rasta Junction
Time Cycl e Cart Wheelere 2-s 3-Wheelere s Other s Wheelere 4-s LCV Bus Truc k Total Veh./h r 8:00 to 9:00 16.5 16.0 763.5 654.0 56.0 503.0 256.2 169.4 226.6 26661.2 9:00 to 10:00 9.5 8.0 1077.0 918.0 32.0 857.0 268.8 147.4 266.2 3583.9 10:00 to 11:00 7.0 4.0 1079.3 1048.0 280.0 832.0 282.8 123.2 264.0 3920.3 11:00 to 12:00 16.5 2.0 1387.5 1152.0 8.0 1002.0 252.0 129.8 286.0 4235.8 12:00 to 13:00 13.0 6.0 1127.3 886.0 14.0 850.0 277.2 83.6 363.0 3620.1 13:00 to 14:00 13.0 0.0 895.5 604.0 56.0 803.0 291.2 145.2 305.8 3113.7 14:00 to 15:00 32.5 34.0 850.5 594.0 28.0 806.0 313.6 193.6 294.8 3147.0 15:00 to 16:00 12.0 28.0 903.8 636.0 16.0 810.0 282.6 334.4 319.0 3342.0 16:00 to 17:00 38.0 46.0 1740.0 1314.0 518.0 1114.0 418.6 149.6 365.2 5703.4
17:00 to 18:00 59.5 26.0 2481.8 1430.0 44.0 1135.0 281.4 180.4 272.8 5910.9 18:00 to 19:00 65.5 10.0 2463.0 1246.0 38.0 1197.0 266.0 202.4 270.6 5758.5 19:00 to 20:00 60.5 26.0 2094.0 920.0 30.0 963.0 277.2 156.2 200.2 4727.1 20:00 to 21:00 34.5 16.0 1676.3 670.0 48.0 721.0 161.0 187.0 143.0 3656.8 21:00 to 22:00 13.5 14.0 924.0 438.0 20.0 504.0 124.6 129.8 149.6 2317.5 22:00 to 23:00 3.0 2.0 483.0 238.0 16.0 300.0 89.6 200.2 96.8 1428.6 23:00 to 24:00 1.0 4.0 214.5 110.0 0.0 241.0 53.2 259.6 103.4 986.7 24:00 to 1:00 0.5 10.0 117.0 78.0 0.0 158.0 29.4 160.6 182.6 736.1 1:00 to 2:00 0.0 2.0 27.8 28.0 0.0 108.0 21.0 68.2 149.6 404.6 2:00 to 3:00 00.0 0.0 21.8 26.0 0.0 79.0 18.2 68.2 99.0 312.2 3:00 to 4:00 0.0 4.0 16.5 22.0 0.0 79.0 40.6 90.2 125.4 377.7 4:00 to 5:00 0.5 16.0 42.8 70.0 4.0 74.0 54.6 178.2 125.4 565.5 5:00 to 6:00 5.5 24.0 99.0 150.0 14.0 171.0 50.4 217.8 116.0 848.3 6:00 to 7:00 45.5 20.0 270.8 510.0 2.0 312.0 65.8 257.4 176.0 1659.5 7:00 to 8:00 21.0 78.0 481.5 586.0 34.0 347.0 68.6 222.2 121.0 1959.3 Total 468.5 396.0 21237.8 14328.0 1258.0 13966.0 4244.8 4054.6 5022.6 64976.3 % 0.72 0.61 32.69 22.05 1.94 21.49 6.53 6.24 7.73 100.0
Hourly Variation of Traffic Volume in Vehicle/hr (Mode wise) onDate:21/08/2010 at Kamrej Char Rasta Junction
Time Cycl e Cart Wheelere 2-s 3-Wheelere s Other s Wheelere 4-s LCV Bus Truc k Total Veh./h r
8:00 to 9:00 48 2 1117 436 40 706 162 69 149 2729 9:00 to 10:00 25 3 1357 413 14 948 190 63 113 3126 10:00 to 11:00 24 1 1866 647 11 1087 230 51 102 4019 11:00 to 12:00 32 1 1964 557 19 1189 246 68 138 4214 12:00 to 13:00 37 2 1793 393 13 852 182 51 117 3440 13:00 to 14:00 19 0 1498 405 12 915 229 72 140 3290 14:00 to 15:00 12 0 1515 422 20 833 196 67 151 3216 15:00 to 16:00 44 5 1405 431 23 865 157 84 132 3146 16:00 to 17:00 81 17 2447 622 15 1159 279 65 152 4837 17:00 to 18:00 97 14 3062 599 14 1315 194 93 101 5489 18:00 to 19:00 158 13 3485 650 27 1253 210 89 141 6026 19:00 to 20:00 93 9 3110 522 13 1191 162 96 106 5302 20:00 to 21:00 58 28 2381 411 0 830 112 105 70 3995 21:00 to 22:00 21 12 1178 276 3 625 104 150 67 2436 22:00 to 23:00 10 8 552 120 10 434 46 97 48 1325 23:00 to 24:00 4 0 303 59 2 310 30 111 48 867 24:00 to 1:00 0 0 86 26 0 181 22 90 79 484 1:00 to 2:00 0 0 64 25 0 138 18 39 61 345 2:00 to 3:00 2:00 0 0 36 14 0 87 16 39 50 242 3:00 to 4:00 0 0 46 30 0 102 41 3 65 337 4:00 to 5:00 4 0 69 42 1 95 18 87 48 364 5:00 to 3 2 102 77 0 138 25 106 59 512
6:00 6:00 to 7:00 35 5 332 120 13 331 42 109 70 1057 7:00 to 8:00 73 5 508 297 5 325 47 92 69 1421 Total 887 127 330276 7594 225 15909 2958 1946 2276 62219 % 1.41 0.20 48.66 12.21 0.41 25.57 4.75 3.13 3.66 100.0
Hourly Variation of Traffic Volume in PCU/hr (Mode wise) onDate:21/08/2010 at Kamrej Char Rasta Junction
Time Cycl e Cart Wheelere 2-s 3-Wheelere s Other s Wheeler 4-es LCV Bus Truc k Total Veh./h r 8:00 to 9:00 24.0 4.0 837.8 872.0 80.0 706.0 226.8 151.8 327.8 3230.2 9:00 to 10:00 12.5 6.0 1017.8 826.0 28.0 948.0 266.0 138.6 248.6 3491.5 10:00 to 11:00 12.0 2.0 1399.5 1294.0 22.0 1087.0 322.0 112.2 224.4 4475.1 11:00 to 12:00 16.0 2.0 1473.0 1114.0 38.0 1189.0 3444 149.6 303.6 4629.6 12:00 to 13:00 18.5 4.0 1344.8 786.0 26.0 852.0 254.8 112.2 257.4 3655.7 13:00 to 14:00 9.5 0.0 1123.5 810.0 24.0 915.0 320.6 158.4 308.0 3669.0 14:00 to 15:00 6.0 0.0 1136.6 844.0 40.0 833.0 274.4 147.4 332.2 3613.3 15:00 to 16:00 22.0 10.0 1053.8 862.0 46.0 865.0 219.8 184.8 290.4 3553.8 16:00 to 17:00 40.5 34.0 1835.3 1244.0 30.0 1159.0 390.6 143.0 334.4 5210.8 17:00 to 18:00 48.5 28.0 2296.5 1198.0 28.0 1315.0 271.6 204.6 222.2 5612.4 18:00 to 19:00 79.0 26.0 2613.8 1300.0 54.0 1253.0 294.0 195.8 310.2 6125.8 19:00 to 20:00 46.5 18.0 2332.5 1044.0 26.0 1191.0 226.8 211.2 233.2 5329.2 20:00 to 21:00 29.0 56.0 1785.8 822.0 0.0 830.0 156.8 231.0 154.0 4064.6
21:00 to 22:00 10.5 24.0 883.5 552.0 6.0 625.0 145.6 330.0 147.4 2724.0 22:00 to 23:00 5.0 16.0 414.0 240.0 20.0 434.0 64.4 213.4 105.6 1512.4 23:00 to 24:00 2.0 0.0 227.3 118.0 4.0 310.0 42.0 244.2 105.6 1053.1 24:00 to 1:00 0.0 0.0 64.5 52.0 0.0 181.0 30.8 198.0 173.8 700.1 1:00 to 2:00 0.0 0.0 48.0 50.0 0.0 138.0 25.5 85.8 134.2 481.2 2:00 to 3:00 0.0 0.0 27.0 28.0 0.0 87.0 22.4 85.8 110.0 360.2 3:00 to 4:00 0.0 0.0 34.5 60.0 0.0 1020 57.4 116.6 143.0 513.5 4:00 to 5:00 2.0 0.0 51.8 84.0 2.0 95.0 25.2 191.4 105.6 557.0 5:00 to 6:00 1.5 4.0 76.5 154.0 0.0 138.0 35.0 233.2 129.8 772.0 6:00 to 7:00 17.5 10.0 249.0 240.0 26.0 331.0 58.8 239.8 154.0 1326.1 7:00 to 8:00 36.5 10.0 381.0 594.0 10.0 325.0 65.8 202.4 151.8 1776.5 Total 439.0 254.00 22707.0 15188.0 510. 15909.0 4141.2 4281.2 5007.2 68436.6 % 0.64 0.37 33.18 22.19 0.75 23.25 6.05 6.26 7.32 100.0
(3)Traffic Volume Survey Analysis:
3.1 Analysis of Traffic Volume Composition:The summary of collected data is as
following. Sr.N
o. Type of Vehicle % of Total Vehicle % of Total Volume in PCU/day 20/08/20 10 21/08/2010 20/08/2010 21/08/2010 A Cycle 1.61 1.41 0.72 0.64 B Cart 0.34 0.2 0.61 0.37 C 2-Wheelers 48.51 48.66 32.69 33.18 D 3-Wheelers 12.27 12.21 22.05 22.19 E 4-Wheelers 1.08 0.41 1.94 0.75 F LCV 23.93 25.57 21.49 23.25 G Bus 5.19 4.75 6.53 6.05
H Truck 3.16 3.13 6.24 6.26
I Others 3.91 3.66 7.73 7.32
3.2 Hourly Variation of Traffic Volume in PCU/hr(DIRECTION WISE)
• FROM SURAT SIDE:
• FROM KIM SIDE:
• FROM KADODARA SIDE: