Basic Components of Road Work Structure
Hi Civil Engineers In this article we will study about the Components of Roads and the Structure of Roads & it’s composition after the reading this article u will understand a lot about the components of road structures. We will try to make it as simple it cann be.
There are few Components of the road structure which we are going to be discuss below which are as follows
RIGHT OF WAY
1. Carriage Way
Carriageway is the width of road on which traffic moves without any restriction. It generally consist of the traffic lines & the width of the carriageway depend on the lines of traffic. Traffic lines are those lines on which traffic can move freely without any restriction. Each country has its own rules for width of the carriageway for insistence how long should it be in some countries for single line road its 2.44m in some its more than that for 2 line its 3.75m in some more then that.
2. Formation Width
The formation width of the road is the sum of carriageway, shoulders and separators ( if there is any ).
Kerb is the boundary line formed from stone or concrete block which separate carriageway form the footpath. There are different types of kerb with different types of the height. There are 4 type of kerb which are low or mountable Krebs, semi-barrier kerb, barrier kerb, & submerged kerb. Iow kerbs are used for the traffic to remain in line & also separate the shoulder from the road so the driver can enter the shoulder area with little difficulty its height is 10cm (4-inch). A semi barrier kerb has height of 15-cm (6-inches). Barrier kerbs has a height of 20-cm (8-inch). They are provided where pedestrian traffic is in considerable amount. Submerged kerb are used in the rural roads the basically provide stability to the road pavement.
4. Road Margin
The part of the road except carriageway are usually called road margin, it includes different parts of road or elements of road which are given below
Sidewalks or footpaths
Shoulders is a part of the formation width except carriage way. Provided alongside the carriageway it’s basically a road for an emergency use for the ambiance in rush hour or to stop a vehicle for repairing propose, & it can be used for the extension of the road in future. The width of shoulders is kept in between 2.5-m to 4.6-m.
2. Bus Bays
Bus bays or bus stops are stationed on the side of the road where the bus can stop safely to pick up passengers or drop off without disturbing the traffic flow they are provided at least 75-m (250-ft) away from intersection of the road.
3. Parking Lines
In urban roads they usually provided parking on the road side & parallel parking is preferred Coz it does not disturb the traffic flow. Its width is 3-m(10-feet).
4. Sidewalks or Footpath
Sidewalks and footpath is a same word When there is the heavy amount of the traffic & pedestrian flow a special paved area is provided for the pedestrian to walk safely on it without any accident.
5. Service Road
Service roads are provided parallel to the main-road & also connect to main highway and expressway. They are separated from the main-road & are connected to highway at selected points. They are provided to not disturb the traffic flow.
6. Cycle Track
Cycle track are provided in those areas where the cycle traffic volume is the high than width of the cycle track is kept between two to three m or in other words (Six to ten ft).
7. Guard Rails
Guard rails are usually provided on shoulder of the road. If the fill is more than 3-m (10-ft) they are provided. Their main is purpose to restrict them from falling of the road & to prevent them from serious accident. Guard rails are made of the different types & in different shapes they are either made of the steel, concrete or stone. They are painted white or yellow for the better visibility.
Medians are provided to the isolate traffic. Their main area purpose is to restrict the collision of the traffic that are moving in the opposite direction of one another.
Camber or cross slope is provided in the middle of the road or carriageway for the drainage of rain water form the road surface. The main purpose of the camber is to prevent water from entering to the subgrade of the road, the road quickly dries which prevent the traffic from slipping off the road which decrease the accident rate. The height of the camber depends upon the material of road & the intensity of rain fall in the region. The value of camber varies from one to 25 or one to 50.
Right of Way
Right of way is the total land require for the construction of the road. Which include carriages way, foot path, & future extension. The right of way depends upon the importance of road for the future extension.
Drive way are join the highway with commercial organizations or buildings such as gas station, filling station, gasoline station, petrol station etc.
Frontage Roads is the constructed to give acquire properties along an essential highway. It may be run parallel to the highway and segregated by separators.
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