Roadbed (noun)

The foundation or base layer of a road, consisting of compacted material such as gravel or crushed stone, on which the pavement is laid.

Origin:

Late 19th century: from road + bed, in the sense "a foundation or base".

Examples:

1. The roadbed was being prepared for the laying of the asphalt pavement.
2. The roadbed was made of crushed stone to ensure stability.
3. The roadbed was raised in certain areas to improve drainage.
4. The heavy trucks caused damage to the roadbed, requiring repairs.
5. The engineers carefully tested the roadbed to make sure it could withstand the weight of the traffic.