Subgrade for pavement, as hereinafter specified,
shall be truly formed to the grade and contour of the finished pavement
surface and, after final shaping and compaction, shall be uniformly
lower than the finished pavement surface by the combined depth of
the pavement base and wearing surface.
[Amended 3-26-1957]
Subgrade shall be formed by such repeated rolling,
shaping, removal of unsuitable material and replacement with suitable
material, rerolling and reshaping as may be necessary to obtain a
uniform, hard, stable surface which does not push or crawl when rolled
with at least a ten-ton three-wheeled roller, which roller or one
giving equivalent compaction shall be used for a final compaction.
Subsurface drainage and/or the addition of gravel or stone shall be
employed where necessary to produce the finished result specified.
