The subbase shall consist of gravel, crusher-run
stone or a combination thereof placed on the subgrade to the depth
shown in the typical sections and constructed in accordance with these
specifications.
All materials for this work shall conform to
the requirements of State Form 810, Article M.02.02.
A.
The prepared foundation for the subbase shall be shaped
carefully to the required cross section and compacted thoroughly.
Where underdrains and outlets are specified on the plans or ordered
by the Town Engineer, they shall be in place and functioning before
any subbase material is placed.
B.
When crusher-run stone or gravel is used, it shall
be spread uniformly upon the prepared grade in layers of not over
six inches in depth after final compaction. An exception herefrom
shall be made when subbase eight inches in depth is specified; it
shall than be laid in one course.
C.
After each layer has been placed as specified above,
it shall be rolled with a ten-ton roller or with an equivalent vibratory
roller or compactor or by a combination of hauling and spreading equipment
and the use of the compacting equipment until thoroughly compacted.
The filler, if required, shall then be applied by spreading in thin
layers lengthwise of the road and the compacting continued, with the
addition of filler as required, until the filler has been thoroughly
forced into the voids and until the entire mass is compacted thoroughly
and satisfactorily.
D.
Should the foundation material beneath the subbase
become churned up and mixed with the subbase material at any time,
the contractor shall remove the mixture and replace it with new subbase
material to the required depth of subbase, as shown on the plans or
as previously required by the Engineer; such replaced subbase material
shall be thoroughly compacted.
