subgrade

listen to the pronunciation of subgrade
İngilizce - İngilizce
The layer of native soil on which the foundation of a road is laid
Road surface shaped and graded before application of rock
The soil prepared to support a pavement structure or a pavement system It is the foundation of the pavement structure
The portion of a roadbed surface that has been prepared as specified, upon which a subbase, base, base course, or pavement is to be constructed
subgrade