Assertion: revetment | /r/HasProperty | tetrahedron blocks
Facets:
value: upon the base
type: LOCATION
Source sentences:
text: 1 is a sectional view partly in elevation illustrating a revetment composed of a gravel base, tetrahedron blocks upon the base, and a filler material between the blocks;
text: 3 is a sectional view partly in elevation of a revetment composed of tetrahedron blocks and a filler material, the gravel bed being omitted; Fig.