What are the four layers of road construction?

Release time：2025-09-28    Click：36

　　The four layers of road construction are:

　　Subgrade: The subgrade is the natural soil or rock layer on which the road is built. It provides the foundation for the road and should be able to support the weight of the road, the traffic, and any other structures on or near the road.

　　Subbase: The subbase is a layer of material placed on top of the subgrade. It provides additional strength and support to the road and helps to distribute the load of traffic more evenly.

　　Base: The base is a layer of material placed on top of the subbase. It provides a stable and durable surface for the road and helps to resist deformation and cracking.

　　Surface: The surface is the top layer of the road and is the part that comes into direct contact with vehicle tires. It should be smooth, durable, and skid-resistant to provide good traction for vehicles.

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