Question

Q.7. Answer the following: (30 marks) 1- Define the urban and rural areas. 2- What are the advantages of shoulders in terms of stabilization and contrast? 3- How to control noise in highway geometric design? 4. You have been asked to design an overpass bridge in Baghdad City. What is the minimum distance required to construct this bridge? Please, support your answer with a suitable sketch and calculations. 5- Explain the importance of widening within the highway geometric design process. 2

Answer 1

Answer 1:

Rural areas are areas with a low population number and low population density. The primary occupation of people in rural areas is agriculture-based or animal rearing in some parts of the world.

Urban Areas are areas with a high population and more densely populated areas. The primary occupation of people there is non-agricultural. Urban area is also more technologically advanced, have well-developed infrastructure and transportation networks.

A clear distinguishment between the rural and urban areas is however not defined.

Answer 2

Advantages of Shoulder are as:

Provide Extra space to drivers for making maneuvers and sudden direction changes in case of an emergency.

Addition area to driver to regain control.

Provide an area/place for damaged/ broken vehicles.

Lateral clearance with roadside objects such as guardrails, poles, signs, etc.

Provide driving ease to drivers.

Provide enhanced space between vehicles and walking pedestrians, increasing their level of comfort

Space for Slow vehicles and cyclists to travel slowly and stop at their will.

Makes existing from the road to side lanes easier and safer.

Answer 3 :

Reducing highway noises through geometrics is a quite difficult task.

1. Planting trees in the median and on either side of the road helps to reduce noise as trees and plants absorb much of the noises.

2. Diverting major highways from outside the city significantly reduces noise for the local residents like planning of ring roads around the city perimeter.

3. Planning flyovers at an elevated profile, facilitate most of the vehicles to take the specified route, reducing congestion and segregating the traffic in a specified direction, eliminating the use of horns. Also, elevated roads cause less noise as compared to at-grade roads due to more easy dissipiation of sound in the air.