A single lane carriage way changing to a two-lane carriage way is affected through a widening process.



The widening process involves expanding the existing single lane carriage way to accommodate two lanes. This is done by adding extra width to the existing road pavement. The steps involved in the widening process are as follows:

1. Survey and Design:
A survey is conducted to determine the existing road conditions, including its alignment, gradient, and any physical constraints. Based on the survey data, a detailed design is prepared for widening the road.

2. Land Acquisition:
In some cases, additional land may be required to widen the road. This may involve acquiring land from adjacent properties or government-owned land. The necessary legal procedures are followed to acquire the land.

3. Clearing and Demolition:
Once the required land is acquired, the existing structures, utilities, and vegetation within the widening area are cleared and demolished to make way for the expanded road.

4. Earthwork:
Excavation and embankment works are carried out to prepare the subgrade for the widened road. Excavation may be required to remove any existing earth or rock materials, while embankment is done by placing suitable fill materials to raise the road level.

5. Pavement Construction:
The widened road pavement is constructed using suitable materials such as granular sub-base, base course, and asphalt or concrete surfacing. The pavement layers are compacted and finished to provide a smooth and durable road surface.

6. Drainage and Utilities:
Proper drainage systems are installed to ensure surface water is effectively drained from the road. Additionally, utility services like water supply lines, sewer lines, and electrical cables may need to be relocated or extended to accommodate the widened road.

7. Road Marking and Signage:
Once the pavement construction is complete, road markings such as lane lines, center lines, and edge lines are painted. Signage boards indicating speed limits, lane directions, and other important information are also installed.

8. Landscaping and Beautification:
Finally, landscaping and beautification works are carried out to enhance the aesthetics of the widened road. This may include planting trees, installing streetlights, and constructing sidewalks or cycle tracks.

Overall, the process of changing a single lane carriage way to a two-lane carriage way involves careful planning, design, and construction activities to ensure a safe and efficient road infrastructure.

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