Intersections: Approved by American Association of State Highway
Officials or other recognized authorities.
2. The present subgrade is
generally well compacted, and the section in being improved in the
course of current maintenance work. Where necessary, the subgrade and
base will be brought to a uniform section by application of select
borrow material. levelled, compacted with water, and rolled. Alsop
where necessary,, a final levelling course of crushed material, 3/4
inch (1.9 centimeters) maximum size, of approximately 1 1/2 inch (3.8
centimeters) thickness will be laid, compacted with water, and
rolled.
3. A conventional
bituminous surface treatment of approximately 1 1/2 inch (3.8
centimeters) will then be applied. as follows.
The surface will be prized with liquid asphalt for
a penetration of approximately 3/4 inch (1.9 centimeters). An armor
coat will be applied using a out-back asphalt and cover stone ,of 5/8
inch (1.6 centimeters) maximum size aggregate. This material will be
rolled with pneumatic and steel wheel rollers. A second armor coat
will be applied, when necessary, after approximately two years from
the date of the first armor coat.
4. Width of the asphalt
surface will be 24 feet (7.3 meters). After application of the second
armor *oat# a center line stripe and shoulder stripes will be applied.
Shoulders will be about 4 feet (1.2 meters) wide. Side slopes will be
3 1/2 to 1 or flatter where feasible and not steeper than I* to I
where fill* exceed 3 feet (0.9 moters) in height or in rook area.
5. Drainage will be
improved where necessary by blading deeper drainage ditches on both
sides of road. Culvert installations will be kept to
|