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High way and Transportation I(DIS) ECIV 4333. Instructor : Dr. Essam Almasri Assistants : Eng.Mustafa abou foul. VOLUME STUDIES. VOLUME STUDIES. Average Annual Daily Traffic (AADT) The average of 24-hour counts collected every day of the year. Average Daily Traffic (ADT)
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High way and Transportation I(DIS) ECIV 4333 • Instructor : Dr. Essam Almasri • Assistants : Eng.Mustafa abou foul
VOLUME STUDIES • Average Annual Daily Traffic (AADT) The average of 24-hour counts collected every day of the year. • Average Daily Traffic (ADT) The average of 24-hour counts collected over a number of days greater than one but less than a year.
VOLUME STUDIES • Peak Hour Volume (PHV) The maximum number of vehicles that pas a point on a highway during a period of 60 consecutive minutes. • Vehicle Classification (VC) With respect to the type of vehicles for cars, two-axle trucks, or three-axle trucks.
VOLUME STUDIES • Methods of Conducting Volume Counts • Manual Method • Automatic Method
VOLUME STUDIES • Hourly expansion factors (HEFs): • Daily expansion factors (DEFs):
VOLUME STUDIES • Monthly expansion factors (MEFs):
Definition • Peak hour factor (PHF): the ratio of total hourly volume to the maximum 15-minute rate of flow within the hour. • PHF (minimum) = 0.25 ( V = Vكل المركبات تمر في ربع ساعة 15) • PHF (maximum) = 1 ( V=4V15المركبات موزعة علي الأرباع بالتساوي ( Steady flow.
Example: • The following traffic counts were made during an hour-long study period: Answer: The hourly volume = 1000+1200+1100+1000 = 4300 veh The rates of low = [ No. of veh.] / [time(in hours)]
Example • In the volume study of Al-Moassasa Street in the old city of Gaza, the following data was collected. for 15 minute periods as shown in the table below. a)Complete the table of data collection. b)Find the peak hour. c)Determine the peak hour volume. d)Calculate the peak hour factor (PHF).
TRAVEL TIME AND DELAY STUDIES • Travel time: is the time taken by a vehicle to traverse a given section of a highway. • Running time: is the time a vehicle is actually in motion while traversing a given section of a highway.
Delay: is the time lost by a vehicle due to causes beyond the control of the driver. • Operational delay:delay caused by the impedance of other traffic. (for example, parking or un parking vehicles).
Fixed delay: is that part of the delay caused by control devices such as traffic signals. This delay occurs regardless of the traffic volume or the impedance that may exist. • Stopped-time delay: is that part of the delay during which the vehicle is at rest.
Methods for Conducting Travel Time 1- Those using a test vehicle • Floating-Car Technique. • Average-Speed Technique. • Moving- Vehicle Technique. 2- Those not requiring a test vehicle. • License-Plate Observations. • Interviews. • ITS Advanced Technologies.
Moving- Vehicle Technique • The observer starts collecting the relevant data at section X-X, drives the car eastward to section Y-Y, then turns the vehicle around and drives westward to section X-X again.
Moving- Vehicle Technique • The following data are collected as the test vehicle makes the round trip: • The time it takes to travel east from X-X to Y-Y (Te), in minutes. • The time it takes to travel west from Y-Y to X-X (Tw), in minutes. • The number of vehicles traveling west in the opposite lane while the test car is traveling east (Ne). • The number of vehicles that overtake the test car while it is t rave ling west from y-y to X-X, that is, traveling in the westbound direction (Ow). • The number of vehicles that the test car passes while it is traveling west from Y-Y to X-X, that is, traveling in the westbound direction (PW).