MD Notes: Items highlighted in yellow are additions to the existing spec.
SECTION 230
RESHAPING ROADWAY AND SUBGRADE PREPARATION
230.01 GENERAL.
This work consists of scarifying, shaping, compacting, and maintaining the subgrade, or
reshaping an existing roadway before constructing a base, or surface course.
230.02 EQUIPMENT.
Equipment
Roadbed Planer
Section
155.02
230.03 MATERIALS.
Material
Water
Aggregate
Section
216
816.03
230.04 CONSTRUCTION REQUIREMENTS.
A.
Reshaping Roadway, Shoulders, and Inslopes.
1.
Reshaping Roadway.
Remove and dispose of following as specified in Section 203.04 D:
 All soft and spongy material
 Rocks larger than 4 inches
 Roots
 Deleterious material
Fill and compact holes and depressions with approved material. Ensure
the subgrade is smooth and compacted.
2.
Shoulder Preparation.
Remove all weeds, grass, dirt, and deleterious material from the
shoulders. Dispose of debris larger than 36 square inches on any surface
as specified in Section 107.10.
Do not commence the overlay of the asphalt shoulder until it is evident
that the vegetation on the shoulder is dead and removed.
3.
Reshaping Inslopes.
Reshape existing inslopes to ensure a smooth transition between the
finished shoulder and the existing inslope.
Provide additional aggregate base material to complete the transitions.
Use the aggregate base material that is specified on the project, or if no
aggregate base material is specified obtain material approval from the
Engineer.
4.
B.
Include all costs for the work described above, including aggregate base
for slough transitions, in the price bid for the item “Shoulder Preparation.”
Topsoil.
Remove, stockpile, and replace topsoil as specified in Section 203.04 B.
Subgrade Preparation.
1.
Subgrade Preparation-Type A.
Scarify, shape, and compact the subgrade to the specified depth.
Scarify the subgrade with a plow and disk.
Dispose of the following as specified in Section 203.04 A:
 Rocks that interfere with trimming the subgrade
 Subgrade material
 Roots
 Deleterious material
Suspend subgrade work in areas where the specified density cannot be
obtained because of excessive moisture.
Compact the subgrade in lifts not to exceed 6 inches of loose material.
Ensure the subgrade is graded to drain at the end of each day.
The Department will set appropriate stakes for use in shaping the
subgrade to the required section and the established grade. Preserve the
line and grade stakes as long as they are needed.
Shape and compact private drives, minor road approaches, and areas of
irregular dimension or restricted access with no specified density.
Ensure the final subgrade elevation is within 0.08 feet of the proposed
subgrade elevation. Do not place base or surface material until the
Engineer approves the subgrade.
a. Shoulder Preparation-Type A.
Scarify, reshape, and compact the top two inches of existing material
to the typical section shown, prior to placing the aggregate base
course material.
b. Reshaping Inslopes-Shoulder Preparation-Type A.
Mow and remove all weeds and grass on the shoulder and upper
inslope area. Reshape the shoulders and inslopes by removing and
redistributing the top 1 inch of material now in place. Dispose of
excavated materials by thin distribution on the inslopes, backslopes,
or open area between the right of way and the backslope as directed
by the Engineer. Remove all material chunks to a site approved by the
Engineer. Include all costs for this work in the item “Subgrade
Preparation, Type A.”
2.
Subgrade Preparation-Type B.
Construct as specified in Section 230.04 B.1 and the trim the subgrade
with a roadbed planer.
The Engineer may permit a base or surface course to be used as a grade
reference for trimming the shoulders.
3.
Subgrade Preparation-Type C.
Construct as specified in Section 230.04 B.1. Trim the subgrade with
equipment using automatic grade control of the cutting edge.
4.
Subgrade Preparation-Type A (Shoulders).
Construct as specified in Section 230.04 B.1.
5.
Aggregate for Subgrade Repair.
Use aggregate to repair subgrade.
230.05 METHOD OF MEASUREMENT.
The Engineer will measure as specified in Section 109.01 and as follows:
A.
Shoulder Preparation.
The Engineer will measure each shoulder separately.
B.
Reshaping Inslopes.
The Engineer will measure each inslope on each side of the roadway separately.
C.
Subgrade Preparation.
The Engineer will not measure areas outside the roadbed, such as private drives,
road approaches, road tapers, and ramps.
D.
Subgrade Preparation-Type A (Shoulders).
The Engineer will measure each shoulder separately.
E.
Topsoil.
The Engineer will not measure topsoil.
230.06 BASIS OF PAYMENT.
Pay Item
Reshaping Roadway
Reshaping Inslope
Shoulder Preparation
Subgrade Preparation-Type__
Subgrade Preparation-Type A Shoulders
Water
Pay Unit
Station, Mile
Station, Mile
Station, Mile
Station, Mile
Station, Mile
M. Gallon
Include the cost of removing, stockpiling, and replacing topsoil along the reshaped inslopes in
the price bid for the reshaping or subgrade preparation items.
Such payment is full compensation for furnishing all materials, equipment, labor, and incidentals
to complete the work as specified.