Transportation Engineering Project

Dr. Lina Shbeeb

Background:

On Sunday 23/5/2010, we worked as a group of six students on a small project for our course "Transportation Engineering" under the supervision of our lecturer Dr. Lina Shbeeb; we have selected a road segment of 200 m from Al-Ordon Street (Jordan Street) to study in general, the dimensions or the road's cross section elements, and some properties related to the traffic volume and capacity.

Our objectives were :1- Define the important elements of the road and state whether they are within the standards or not.

2- Study the facilities that the road has and state if there are any other needed facilities.

3- Comment on the existing road status and suggest important points to improve it.4- Calculate the Time Mean Speed (TMS) and Space Mean Speed (SMS).

5- Calculate the Traffic Flow and Density (concentration) in the given road segment.

Approach:

Time: Sunday 23/5/2010 between 11:00 AM and 1:00 PM

Location: Jordan Street Al-Istiklal Bridge, the first 200 m segment to the north towards The North Bus Station (Mojama'a Al-Shamal).

Flow Direction: South Bound.

To deal with this project, and to find the needed information, data about vehicles passing this road segment were collected using the appropriate methods (as we'll describe in the next section), data about vehicle types were taken, data about time needed for some vehicles to pass the segment were recorded for a sample of at least 100 vehicle of various types.Also, information about the road's elements and dimensions were taken to study the design and the current status of the road.

In addition, some photos were taken to the road and to some important facilities.

Methodology:

Data Collection:

As mentioned earlier, a sample of 100 vehicle were taken and the needed time for every vehicle to fully clear the section's length is recorded.

Equipments such as steel measurement tape were used to determine the required length for this study, and to obtain the dimensions of the roadway elements, also a stop watch and a cell-phone were used to record the time needed for every vehicle.

Data Collection Process:

Our 6-member group were divided into 3 groups, the first group which consists of 2 students collected data about the dimensions, the second and third groups collaborated for the vehicle data collection, the second group contained 3 students took the beginning of the road segment, one of them collected data about the number of vehicles that have passed the segment in a time period of 15 minutes, the other two were connected to the third group through a cell-phone all the time.

Now the process through which the last four students worked can be summarized as follows:

The first two students had to select a car and give it a name consisting from its make and the last 2 digits from its license plate (i.e Toyota 94, Mercedes 11,) and as the defined vehicle passes the start point of the segment, the stop watch is started, and then by the cell-phone, the vehicle's given name is defined to the third group which is taking the position of the finish point of the segment, and as the vehicle passes the finish point, the third group reports that back to the second group and the stop watch is then stopped, and so on for all vehicles.For example:

Second group: vehicle BMW with 90 as its license plate's last two digits has just passed the start point.

This event is recorded by one of the second group's student, while the other one has to start the stop watch.

The vehicle's defined name is then reported for the third group, and just as the vehicle passes the finish point, the third group reports this event, and then the stop watch student stops the watch, and the measured time is recorded for the corresponding vehicle.Data Collected:

The following represents the data taken from the sight of interest:First: Cross Section dimensions ..

Road width = 14.07 m

Number of lanes = 3

Lane width = 3.8 m

Inner shoulder = 0.37

Side walk = 1.3 m

Median = 2 m

Outer shoulder = 0.54 m

Notes taken from the field on the above dimensions:

1- the left and middle lanes have a width of 3.8 m, while the right lane has a greater width with no markings to separate it from the shoulder.

2- The road width is taken yellow marking line to yellow marking line (i.e. from the yellow marking on the left to the yellow marking of the right).

3- The median has at some segments steel barriers.

4- The side walk differs in width from point to another, but the average is taken and indicated above.

5- The street has no parking sides, and no emergency stopping areas, plus the shoulders are too small, and if a vehicle stops there, its interrupts the traffic closest to its (right lane).6- Though the area is somehow residential, no appropriate pedestrian facilities exist except a pedestrian bridge.

7- No green strip is used in the side walk, but trees are every where on the road sides.

8- The markings are not clear to be seen on the pavement.9- The pavement is not good, and it might causes accidents, and it needs rehabilitation.

10- The road sides should have more facilities for pedestrian since its a residential area and its a commonly used as a walking area.

11- There must be a wider emergency stopping area, in case a vehicle is forced to stop.

Note: more notes about the cross sections elements will be included in the following section which talks about comparisons between the ideal and the existing dimensions.

Second: vehicles Data:During a time period of 15 minutes, the following numbers of different vehicle types were recorded:

PCTruckTaxi

Numbers47050130

Note: for calculations, the truck factor is taken as 2.

Also, the following Data were recorded for a total vehicle number of 100, between 12:00 1:00 PM.

From the previous information and calculations we can conclude the following:

First: the flow for the studied roadway:

Second: by taking a section with length 200 m from the road and apply road tube study method we found the time mean speed:

Where (n): number of vehicles

Third: for the same section we used a stopwatch to determine the space mean speed (SMS):

Where (L): length of the section.

Fourth:

Density is the number of vehicle travelling over a unit length at a given instant.

Also, the density can be calculated using the following formula:

Remarks:1- our study is based on an arterial roadway.

2- Posted speed on roadway is 60 km/hr (speed limit).

3- The studied roadway has three lanes in one direction.

4-We can do small compare between the actual value and the standard value using the following table:

Inner shoulder (cm)Outer Shoulder (cm)Sidewalk (cm)Lane Width (m)

Actual Value37 541303.8-3.9

Standard Value60-36060-360120-1503.6

Discussion and Conclusion:By observing the recorded Data, its rightly said that the real life is not always like the theoretical one, and what we have studied through this course is not always applied to the existing facilities on the roadway networks._1336200468.unknown

_1336201722.unknown

_1336202196.unknown

_1336202472.unknown

_1336201579.unknown

_1336200227.unknown

_1336200328.unknown

_1336200119.unknown