Editor's Note: This article was adopted 9-4-1984 by Ord. No.
1050 and amended 7-6-1987 by Ord. No. 1134; 11-6-1991 by Ord. No.
1267; and 4-3-2006 by Ord. No. 1523.
Grading. The subgrade shall be brought to a firm unyielding surface
by rolling the entire area with a power roller weighing not less than
10 tons. Rolling shall be done from the sides to the center for the
full distance of that portion to be paved and shall be continued until
the subgrade is thoroughly compacted. Solid rock, boulders, soft clay,
loose, flaky or spongy material which will not consolidate under the
roller shall be removed from the subgrade. The space shall be filled
with clean, dry dirt, or other suitable material, and the subgrade
rerolled until it presents a smooth, even surface of proper shape
and cross section.
General. After the subgrade has been properly prepared and compacted,
there shall be constructed a two-course crushed stone base course
having a total depth of eight inches after compaction. No subbase
is required if a crushed stone base course is used.
The course material shall be Type A or better, stone or slag, meeting
the requirements for No. 1 aggregate and shall be uniform in quality,
graded and of such size as to conform with Table C, Size and Grading
Requirements for Course Aggregate, Section 703.2 of Form 408, or the
equivalent section in any revision of Form 408.
The fine material shall be Type A or better, stone or slag, meeting
the requirements for No. 10 aggregate and shall be uniform in quality,
graded and of such size as to conform with Table C, Size and Grading
Requirements for Course Aggregate, Section 703.2 of Form 408, or the
equivalent section in any revision of Form 408.
The crushed stone base course shall be constructed of two layers
with the bottom layer having a compacted depth of five inches. The
course material shall be spread uniformly by approved mechanical stone
spreaders to the full width of the road.
Spreaders shall be adjusted to spread the loose material to obtain
a layer of the required depth after compaction. The course material
shall not be spread for a distance of more than an average day's work
ahead of choking and compacting. The course material shall be rolled
and thoroughly compacted with an approved three-wheel roller. The
rolling shall begin at the sides and progress to the center uniformly
lapping each preceding track and continuing until the material does
not creep or wave ahead of the roller wheels.
After the course material has been satisfactorily rolled and compacted,
fine material shall be uniformly spread over the surface with approved
mechanical equipment. The fine material shall be broomed and rolled
until the voids in the course material are completely filled and the
base course is thoroughly compacted and firmly set.
General. After the subbase has been properly prepared and compacted
to a depth of three inches, there shall be constructed a two-course
Superpave 25.0 mm base course having a total depth of 5 1/2 inches
after compaction.
The fine aggregate for bituminous mixtures shall be reasonably uniform
in its physical properties and shall meet the grading and quality
requirements specified in the current Pennsylvania Department of Transportation,
Form 408. The material shall be natural sand and/or stone sand, composed
of hard, tough, durable, uncoated particles, free from clay, silt,
vegetation or other substances determined to be deleterious.
The course aggregate shall be Type A stone, gravel or slag reasonably
uniform in its physical properties and shall meet the requirements
for No. 1B and No. 2B material specified in the current Pennsylvania
Department of Transportation Form 408. The material shall be composed
of hard, tough, durable, uncoated particles, free from harmful amounts
of clay, silt, vegetation or other substances determined to be deleterious.
Composition. The aggregate and bitumen meeting the requirements herein
specified shall be combined in such proportions that the total aggregate
and the bitumen in the base course will conform to the compositions
by weight percentages as specified by the Engineer.
Superpave 25.0 mm base course shall not be placed on wet surfaces
nor when the air temperature is 35° or lower, nor when the temperature
of the subbase is 35° or lower. The base course material shall
be hauled to the site in tight vehicles with approved covers of sufficient
size and quality to protect the entire load and to ensure that the
mixture is delivered at the correct laying temperature, free from
lumps of chilled material.
The base course shall be constructed of two layers with the bottom
layer having a compacted depth of three inches. The mixture shall
be spread or struck off by mechanical spreading and finishing equipment
for the entire width or for such partial-width lanes as may be practical.
The screed assembly shall be adjustable to give the cross section
required and shall be designed and operated to provide the required
depth.
Immediately after the bituminous mixture has been spread, struck
off and surface irregularities adjusted, it shall be thoroughly and
uniformly compacted by rolling. The rollers shall be normally operated
so that the breakdown rolling is performed with a three-wheel or tandem
roller. The rolling shall start longitudinally at the sides and gradually
progress toward the center of the road, overlapping on successive
trips by at least 1/2 the width of the roller. Rolling shall be continued
until the rolling does not cause undue displacement, cracking or shoving.
The wheels of steel-wheel rollers shall be kept moist and clean to
prevent adhesion of the fresh material, but an excess of water will
not be permitted.
Any mixture that becomes loose and broken, mixed with dirt, or is
in any way defective, shall be removed and replaced with fresh hot
mixture, which shall be compacted to conform with the surrounding
area.
General. After the subgrade has been properly prepared and compacted
there shall be constructed a two-course crushed stone base course
having a total depth of eight inches after compaction. No subbase
is required if a crushed stone base course is used.
The course material shall be Type A or better, stone or slag, meeting
the requirements for No. 1 aggregate and shall be uniform in quality,
graded and of such size as to conform with Table C, Size and Grading
Requirements for Course Aggregate, Section 703.2 of Form 408, or the
equivalent section in any revision of Form 408.
The fine material shall be Type A or better, stone or slag, meeting
the requirements for No. 10 aggregate and shall be uniform in quality,
graded and of such size as to conform with Table C, Size and Grading
Requirements for Course Aggregate, Section 703.2 of Form 408, or the
equivalent section in any revision of Form 408.
The crushed stone base course shall be constructed of two layers
with the bottom layer having a compacted depth of five inches. The
course material shall be spread uniformly by approved mechanical stone
spreaders to the full width of the road.
Spreaders shall be adjusted to spread the loose material to obtain
a layer of the required depth after compaction. The course material
shall not be spread for a distance of more than an average day's work
ahead of choking and compacting. The course material shall be rolled
and thoroughly compacted with an approved three-wheel roller. The rolling shall begin at the sides and
progress to the center uniformly lapping each preceding track and
continuing until the material does not creep or wave ahead of the
roller wheels.
After the course material has been satisfactorily rolled and compacted,
fine material shall be uniformly spread over the surface with approved
mechanical equipment. The fine material shall be broomed and rolled
until the voids in the course material are completely filled and the
base course is thoroughly compacted and firmly set.