The order in which a road is built isa)sub-soil, base, sub-grade, sub-baseb)base, sub-soil, sub-grade, sub-basec)sub-base, base, sub-grade, sub-soild)sub-soil, sub-grade, sub-base, baseCorrect answer is option 'D'. Can you explain this answer?

Question

Answer

The lowest layer of road is soil which is naturally compacted called sub soil after that the second layer which is also soil but properly compacted by machine or else which is called sub grade and third layer which is layer of small size gravel called sub base and the last one is base coarse which have size greater than sub base.
So we can say option (d) is correct sequence for road construction.

Answer

Answer

B

Answer

The correct order in which a road is built is:
d) sub-soil, sub-grade, sub-base, base

Explanation:
1. Sub-soil:
The first step in building a road is preparing the sub-soil. Sub-soil refers to the natural ground on which the road is constructed. It is important to ensure that the sub-soil is stable and able to support the road structure. This may involve removing any weak or unsuitable soil and replacing it with more suitable material.

2. Sub-grade:
Once the sub-soil is prepared, the next step is to construct the sub-grade. The sub-grade is the layer of soil or material that is placed on top of the sub-soil. It serves as a foundation for the road and helps to distribute the load evenly. The sub-grade is typically compacted to ensure stability and to minimize settlement.

3. Sub-base:
After the sub-grade is constructed, the sub-base is built on top. The sub-base layer is made up of a coarser material such as crushed stone or gravel. It provides additional support to the road structure and helps to prevent the intrusion of water from the sub-soil. The sub-base is also compacted to ensure stability and to create a solid base for the road.

4. Base:
Finally, the base layer is constructed on top of the sub-base. The base layer is typically made up of a mixture of aggregates, such as crushed stone or asphalt, that provide strength and stability to the road. It acts as a load-bearing layer and helps to distribute the traffic loads evenly. The base layer is also compacted to ensure a smooth and durable road surface.

Summary:
In summary, the correct order in which a road is built is sub-soil, sub-grade, sub-base, and base. This sequence ensures that the road is built on a stable foundation and that each layer provides the necessary support and functionality for the road structure. The proper construction of these layers is essential for the long-term durability and performance of the road.

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