Exercise 28 Pavement Base and Setting Bed Preparation 115
115
Pavement Base and Setting
Bed Preparation
OBJECTIVE
The objective of this exercise is to properly prepare a
TEXTBOOK REFERENCE
Information related to this activity can be found in the
INTRODUCTION
The success of a paving project begins with the installa-
tion of a sound base upon which to build. Regardless of
the type of paving to be placed, the lack of solid support
base will eventually lead to maintenance and durability
When installing unit pavers or dry-laid stone, a setting bed
of concrete sand will need to be placed over the granular
• Stake the site to be paved. The area that needs
to be prepared for the base will typically extend
12 inches outside the dimensions of the proposed
and cross-slope of the subgrade often by running
a string between the grade stakes and measuring
down with a tape measure (Figure 28–2).
• Examine subgrade for potential soil and water
problems. Remaining topsoil, soils that are soft,
or soils that contain vegetative matter should be
removed to a depth of 12 inches and replaced
Exercise 28
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116 Exercise 28 Pavement Base and Setting Bed Preparation
• Run a vibratory plate compactor over the surface
after each lift. Work from the outside edges into
the center, and then repeat at a 90° angle to the
direction of the first pass.
• Select clean, coarse, damp, concrete sand for
the setting bed. Dry sand will need to be sprayed
lightly with water before screeding.
Project edge
Verify depth by adding
thickness of paver, setting
bed, base, and slope;
typ. 8″
Stringline for
checking depth
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Exercise 28 Pavement Base and Setting Bed Preparation 117
• Screed only the area of setting bed that will be
immediately paved. Small sections may need to be
screeded to match existing grades.
• When screeding is complete, lift out any
temporary screed rails. Fill the voids left by the
rails with additional sand. Smooth the fills to
match the surrounding level with a steel trowel.
Construction Staking, and Exercise 9, Grade Staking,
before beginning this exercise.
MATERIALS REQUIRED
• Proper clothing and safety gear
• Wheelbarrows
Placing
base material Compacting
base material
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118 Exercise 28 Pavement Base and Setting Bed Preparation
CAUTION
• Sod cutter (prepared for operation)
• Vibratory plate compactor (prepared for
operation)
• Two 25 foot tape measures
• Surveyor’s flags
• Marking spray paint
• Class 2 aggregate base material
• Clean, coarse concrete sand
high side to the low side. When the base is complete,
install a 1 inch deep sand setting bed over the entire
paved area.
Operate power equipment under supervision.
Serious injury or death could result
from improper use of equipment. Follow
manufacturer’s instructions.
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