City of Frisco Engineering Standards

SECTION 321314
ROLLING
PART 1 - GENERAL
1.01 DESCRIPTION
A. All material, labor, equipment, tools and superintendence necessary for Rolling in accordance
with Public Works Construction Standards, NCTCOG, 4 th Edition, Item 301.1.2.
1.02 REFERENCES
A. Public Works Construction Standards, NCTCOG, 4 th Edition, Item 301.1.2
PART 2 - PRODUCTS
2.01 MATERIALS
A. TAMPING ROLLER
1. Tamping rollers shall consist of two (2) metal rollers, drums or shells of not less than
forty inches (40") in diameter, each not less than forty-two inches (42") in length and unit
mounted in a rigid frame in such a manner that each roller may oscillate independently of
another. Each roller, drum or shell shall be surmounted by metal studs with tamping feet
projecting not less than seven inches (7") from the surface and spaced not less than six
inches (6") nor more than 10 inches (10") measured diagonally center to center; and the
cross-sectional area of each tamping foot measured perpendicular to the axis of the stud,
shall be not less than five square inches (5") nor more than eight square inches (8"). The
roller shall be of the type that by ballast loading, the load on each tamping foot may be
varied uniformly from 125 p.s.i. of cross-sectional area. The load per tamping foot will
be determined by dividing the total weight of the roller by the number of tamping feet in
one row parallel to or approximately parallel to the axis of the roller.
2. The tamping roller shall be drawn by approved equipment of adequate tractive effort.
Power equipment used in embankment construction shall be the crawler type tractor.
Two (2) tamping rollers conforming to the above requirements, drawn by approved
equipment, shall be considered a roller unit.
B. TIRE ROLLER
1. Tire rollers shall consist of not less than nine (9) pneumatic-tired wheels, running on
axles in such a manner that the rear group of tires will not follow in the tracks of the
forward group of wheels, and mounted in a rigid frame, and shall be of a type suitable for
ballast loading. The distance between the front and rear axles shall be not less than five
feet (5') no more than 10 feet (10').
2. The front axle shall be attached to the frame in such a manner that the roller may be
turned in a minimum circle. The pneumatic tire roller shall have an effective rolling
width of approximately sixty inches (60"), and shall be ballast loaded so that the load
may be varied uniformly from not less than 100 p.s.i. of width of tire tread to 325 pounds
per inch of tire tread. The roller, under working conditions, shall provide a uniform
compression under all wheels. The total combined width of effective tire tread shall be
not less than eighty-five percent (85%) of the effective rolling width. The pneumatic tire
City of Frisco May 2012
Standard Technical Specification Rolling 321314-1