2010 Construction and Material Specifications - Ohio Department of ...

204.06
is part of the pavement design, reduce the above 2-foot (0.6 m) undercut by the
thickness of the aggregate base or bases. Maintain a total undercut depth of 2 feet
(0.6 m) below the bottom of the asphalt or concrete pavement.
Excavate for a width of 1 foot (0.3 m) beyond the shoulders. Replace with
suitable material according to 204.07.
204.06 Proof Rolling. Perform the testing of the stability and uniformity of
the subgrade compaction in locations shown on the plans by proof rolling.
Use a proof roller conforming to the following:
A. Four heavy pneumatic tire wheels mounted on a rigid steel frame.
B. Wheels evenly spaced in one line across the width of the roller.
C. Wheels arranged so that all wheels carry approximately equal loads when
operated over an uneven surface.
D. A maximum center-to-center spacing between adjacent wheels not exceeding
32 inches (0.8 m).
E. A body for ballast loading capable of varying the gross load from 25 to 50
tons (23 to 45 metric tons).
F. Tires capable of operating at inflation pressures ranging from 90 to 150
pounds per square inch (620 to 1040 kPa). Provide a tire pressure gage for
measurement before use.
G. Tires filled with liquid from 90 to 95 percent by volume.
Provide ballast that consist of ingots of known weight, sand bags with a weight
of 100 pounds (45 kg), bags of other material of known weight, or other suitable
material such that the total ballast weight is readily determinable at all times.
Provide sufficient ballast to load equipment to a maximum gross weight of 50 tons
(45 metric tons).
Furnish the Engineer information verifying that the weights and tire pressures
can be met.
After compacting the subgrade according to 204.03 and before placing
overlying course, proof roll designated subgrade areas. If proof rolling is
performed after the underdrains are installed, do not use the proof roller within 1
1/2 feet (450 mm) of the underdrains.
Ensure that the subgrade moisture content at the time of proof rolling is within 2
percent of the moisture used for acceptance in 204.03.
Adjust the load and tire inflation pressure according to the following:
A. For soils classified as A-3, A-4, A-6, or A-7-6, use a 35-ton (32 metric tons)
roller with a tire pressure of 120 pounds per square inch (820 kPa).
B. For granular soils, and soil, rock, and granular mixtures, use a 50-ton (46
metric tons) roller with a tire pressure of 150 pounds per square inch (1030 kPa).
C. Measure the tire pressure in the presence of the Engineer.
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