[Amended 12-12-1978]
A.
In the interest of keeping these specifications brief, where reference
is made herein to "state specifications," it shall mean the State
of New York, Department of Public Works, Division of Construction,
Public Works Specifications of July 2, 1973, including all addenda
and latest revisions thereto, but excluding the method of measurement
and payment therein. Wherever in the state specifications the words
"engineer," "deputy chief engineer," "inspector" or like terms are
used, they shall be construed to mean the Town Board or its duly authorized
representative. Wherever the initials "AASHTO" are used, reference
is made to the current specifications and tests of the American Association
of State Highway and Transportation Officials.
B.
All materials and/or methods of construction not described in these
construction standards and specifications shall meet the requirements
of the current state specifications.
A.
Clearing and grubbing.
(1)
All trees and brush within the limits of the area to be graded must
be cleared. On curves, an additional amount shall be cleared wherever
necessary to maintain visibility along the inside pavement edge of
at least 150 feet.
(2)
All dead trees or those in a hazardous condition within the right-of-way
or adjacent to it and in danger of falling into the right-of-way shall
be removed. Under certain conditions this may include a strip above
the upper limits of cut slopes.
[Amended 12-12-1978]
(3)
The Planning Board may waive the clearing of certain trees upon request,
or upon its own initiative may request that certain trees within the
right-of-way be preserved.
(4)
All roots and stumps within the limits of areas to be graded shall
be grubbed and excavated to a depth of two feet below the final finished
grade except in fills greater than two feet where they shall be cut
flush with the ground surface. Otherwise, where trees are cleared
and grubbing is not required, the trunks shall be cut off not more
than six inches above the original ground surface.
(5)
Walls, footings, etc., shall be removed to a depth of at least two
feet below the proposed finished grades. Such areas shall be backfilled
and graded over.
B.
Stripping. The developer shall strip all topsoil from the bed of
the proposed roadway and from all surfaces to be disturbed by cut
or fill. Topsoil shall be kept separate from all other classes of
excavated materials and shall be stockpiled on the site for finished
grading. It shall not be removed from the property except in compliance
with the Town ordinances.
C.
Unsuitable material. All unstable material such as muck, humus, spongy
material, soft clay, bogs and any other objectionable materials below
the proposed subgrade shall be removed and the area filled with acceptable
materials and well compacted.
D.
Preparation of subgrade.
(1)
The subgrade shall be brought to the required grade by excavation
or filling. All suitable and acceptable material from excavation shall
be used for making embankments and backfilling as required. Tree trunks,
limbs and other perishable materials shall not be incorporated in
the fill, but shall be removed.
[Amended 12-12-1978]
(2)
All grading shall be done to conform to the approved construction
plan and profiles and to provide a completed cross section as shown
on the construction standards.
(3)
Side slopes shall have a graded slope of not more than one foot vertical
for each two feet horizontal in cut or fill in earth, and not more
than six feet vertical for one foot horizontal in rock.
(4)
Backfill for all drainage structures and culverts shall be as specified in § 195-31B.
[Amended 12-12-1978]
(5)
The subgrade shall be formed by repeated rolling, shaping, removal
of unsuitable material and replacement with suitable materials, rerolling
and reshaping until a uniform hard, stable surface properly crowned
to shed water laterally is provided.
(6)
Embankments shall be formed of suitable and acceptable excavated
materials. The fill shall be spread in layers not to exceed 12 inches
in depth extending across the entire fill area. It shall be bladed
or spread to an even surface, free from all clods and thoroughly compacted
by rolling with approved rollers. Successive layers shall not be placed
until the layer under construction is thoroughly compacted. Sections
not accessible to the roller may be backfilled in eight inch layers
and compacted with approved mechanical hand tampers.
(7)
Fill within 12 inches of finished grade shall be free of stone larger
than six inches in greatest dimension.
(8)
All hollows and depressions which develop during the process of rolling
and compacting shall be filled with acceptable materials, and the
subgrade shall again be compacted.
(9)
Filling and compacting operations shall continue alternately until
no depressions result and the subgrade conforms to the lines, grades
and typical cross sections shown on the approved road plans.
(10)
If there is not sufficient excavated material of a suitable
quality within the limits of work to complete embankments, grading
and the backfilling to required lines and grades, the material may
be brought in from outside sources subject to the quality being approved
by the Town.
(11)
Any surplus suitable material shall be used for extending the
shoulders to a greater uniform width or for flattening the embankment
slopes or shall be deposited in spoil areas.
(12)
Excavations for head walls shall be made large enough to provide
adequate clearance and depths for construction and accurate lines
and grades.
(13)
Trenches for pipes shall be excavated to the required line and
grade, shall have a firm finished bottom to grade and shall be of
sufficient width to lay pipes, enable caulking and jointing to be
done advantageously and to permit thorough tamping of backfill.
(14)
Selected materials only shall be used for backfill, free from
large lumps, clods, stone or rock, and placed in layers not exceeding
six inches in depth, each layer being thoroughly compacted.
(15)
Ledge rock in trenches shall be removed below grade and replaced
with a compacted earth cushion of suitable materials at least eight
inches in depth below the pipe.
E.
Blasting. Explosives shall be stored and used in conformity with
state laws and Town ordinances. Both state and Town permits must be
obtained.
F.
Slope grading. Prior to installation of bank gravel foundation, course
slopes shall be laid back to proper grade, scarified, topsoiled and
seeded. This shall be done in conjunction with the erosion control
standards. No more than 500 feet of road shall be brought to subgrade
without bank stabilization.
[Added 12-12-1978]
A.
General. All road pavements shall be composed of five inches of asphalt
consisting of 3 1/2 inches of binder and 1 1/2 inches of
top course. Thicknesses stated are after compaction.
[Amended 12-12-1978]
B.
Conditions for laying of pavement. The laying of asphalt concrete
and penetrated macadam pavement will be permitted between April 15
and November 15, when the air temperature is 50° F. and rising
or warmer and the temperature of the surface on which the paving is
to be laid is 45° F. or higher. Such paving at other times
or conditions will require the written permission of the Town's Engineer.
C.
Bank gravel foundation course. Foundation course for all roads shall
be of crushed run-of-bank gravel placed on a properly prepared subgrade
to the compacted thickness shown on the construction standards.
(1)
Acceptable material. Material acceptable for foundation courses shall
consist of sound, hard, durable gravel, well-graded from coarse to
fine. Particles shall have a maximum diameter equal to 2/3 of the
thickness of the compacted layer of the foundation course under construction,
but shall not exceed such size as will pass through a two-inch-square
screen. Thirty percent to 65% by weight shall pass a one-fourth-inch-square
mesh sieve, and not more than 10% by weight shall pass a No. 200 mesh
sieve. The material passing a No. 40 mesh sieve shall have a maximum
Plasticity Index of 5, when tested according to ASTM D424. When the
material is subjected to four cycles of magnesium sulphate soundness
test (ASTM C88), the weighted loss shall not exceed 20%. All material
acceptable for this course shall contain suitable proportions of coarse
and fine particles so that by the addition of proper amounts of water,
a thoroughly stable, well-bound course will be produced whose surface
will not weave or be displaced after compaction.
(2)
Spreading and compaction.
(a)
After the subgrade has been properly prepared, the gravel shall
be spread evenly so that it will have, after rolling, the proper thickness.
No segregation of large or fine particles will be allowed, but the
gravel as spread shall be well graded, with no pockets of fine material.
(b)
The finished thickness of the foundation course shall consist
of one four-inch layer of crushed gravel spread, rolled and filled,
plus an additional four-inch layer of crushed gravel spread, rolled
and filled.
(c)
After the gravel has been spread, it shall be thoroughly rolled
with an approved roller weighing not less than 10 tons. All holes
or depressions found in rolling shall be filled with gravel and the
surface rerolled until it conforms to the lines and grades as shown
on the construction standards and the approved construction plans
for the particular subdivision. In all cases, the foundation course
shall be true to grade and section, and so thoroughly compacted that
it will not weave under a roller.
D.
Asphalt concrete.
(1)
General requirements. Asphalt concrete pavement shall be constructed
as shown on the construction standards. Asphalt concrete up to two
inches in thickness shall consist of one top course meeting all requirements
of Item 51, Asphalt Concrete, Type 1A, top course only, of the state
specifications. Asphalt concrete over two inches in thickness shall
consist of two equal thicknesses of binder and top courses meeting
all requirements of Item 51, Asphalt Concrete, Type 1A, of the state
specifications.
(2)
Priming or penetration of previous course.
(a)
Where asphalt concrete pavement is to be placed on a crushed
bank-run gravel foundation, the foundation course shall be primed
with a medium curing liquid asphalt, Grade MC-1, as per ASTM D598,
heated to a temperature between 80° F. and 150° F.
It shall be applied uniformly over the surface by means of pressure
distributors at a rate of 0.2 gallon to 0.6 gallon per square yard,
dependent on the gradation of the surface, to ensure a minimum penetration
of one inch.
(b)
Where asphalt concrete pavement is to be placed on a penetrated
macadam base, the macadam base shall be constructed as specified by
the Town Engineer.
(3)
Composition of binder course. Composition of the bituminous plant
mixture for the binder course shall conform to the following:
Screen Size
(inches)
|
General Limits
Percent Passing
|
Job Mix Percent Tolerance
| |
---|---|---|---|
1 1/2
|
100%
|
0
| |
1
|
90% to 100%
|
+/-5
| |
1/2
|
35% to 65%
|
+/-6
| |
1/4
|
10% to 35%
|
+/-4
| |
1/8
|
5% to 20%
|
+/-3*
|
Type of Mix
|
Percent of Mix
|
Job Mix Percent Tolerance
| |
---|---|---|---|
Hydrated lime
|
0.5 to 1.0
|
+/-0.2
| |
Liquifier
|
0.4 to 1.0
|
+/-0.2
| |
Asphalt cement**
|
4.0 to 5.5
|
+/-0.4
|
NOTES:
| ||
---|---|---|
*
|
The No. 20 mesh screen and subsequent screens do not apply to
the aggregates of the binder courses passing the one-eighth-inch screen.
| |
**
|
Asphalt cement shall be as specified in Subsection D(5), Composition of asphalt cement.
|
(4)
Composition of top course. Composition of the bituminous plant mixtures
for the top course shall conform to the following:
Screen Size
|
Type 1A, Hot Process General Limits Percent Passing
|
Job Mix Percent Tolerance
| |
---|---|---|---|
1 inch
|
100%
|
0
| |
1/2 inch
|
95% to 100%
|
+/-5
| |
1/4 inch
|
65% to 85%
|
+/-5
| |
1/8 inch
|
32% to 65%
|
+/-6
| |
No. 20 mesh screen
|
15% to 39%
|
+/-7
| |
No. 40 mesh screen
|
7% to 25%
|
+/-6
| |
No. 80 mesh screen
|
3% to 12%
|
+/-3
| |
No. 200 mesh screen
|
2% to 6%
|
+/-2
|
Type of Mix
|
Percent of Mix
|
Temperature
|
Job Mix Percent Tolerance
| |
---|---|---|---|---|
Asphalt cement
|
5.8 to 7.0
|
—
|
+/-0.4
| |
Penetration of asphalt cement
|
—
|
85° F. to 100° F.
|
—
| |
Placing temperature
|
—
|
225° F. to 300° F.
|
—
|
(5)
Composition of asphalt cement. The asphalt cement used in the binder
and top courses shall be a paving grade asphalt meeting the requirements
hereafter specified, and shall be introduced into the pugmill at a
temperature compatible with the aggregates between the limits of 225° F.
and 350° F. Asphalt cement shall conform to the following:
Type
|
Specification
| |
---|---|---|
Grade
|
85 to 100
| |
Water
|
0.0
| |
Homogeneous
|
Yes
| |
Pen. @ 77° F. 100 g. 5 sec.
|
85 to 100
| |
Pen. Ratio (39.2° F./77° F. x 100)
|
30.0+
| |
% Loss @ 325° max.
|
See Note A below
| |
% Pen. of Res. min.
|
60.0
| |
% Sol. in CCI4 min.
|
See Note B below
| |
Flash Point, °F. min.
|
347
| |
Duct. @ 77° F. min.
|
60
|
Note A: 1.0% limit for Pet. Asphalts; 3.0% for Fluxed Nat. Asphalt.
| |
Note B: 99.5+ Pet. Asphalts; 95.0+ Bermudez; 81.0+ Cuban; 66.0+
Trinidad.
| |
Method of tests: AASHTO
|
(6)
Approval of job mix formulas. The subdivider shall submit to the Town's engineer for approval the actual job mix formulas. Once approved, the composition of the mix shall lie within the job mix tolerance set forth in Subsection D(3), Composition of binder course, or Subsection D(4), Composition of top course, of these specifications. The aggregate tolerances shall be based on the total weight of the aggregate, and the asphalt cement tolerances shall be based on the total weight of the mix. In no case shall the job mix tolerances fall outside the general limits for a particular mix. Before approving the paving, the Planning Board shall require the subdivider to submit a certificate from a responsible representative of the plant supplying the paving mixture, stating the compositions, daily quantities and delivery dates of the mix furnished to the subdivider.
(7)
Asphalt concrete; method for rolling.
(a)
After placing, and while still hot and workable, the course
shall be rolled with a ten- to twelve-ton, three-wheel, power-driven
roller, an eight- to ten-ton tandem roller or a roller producing a
compression with the rear wheels of not less than 250 pounds per inch
of tread. Rollers shall have steel wheels and shall travel parallel
to the center line of the pavement, beginning at each edge and working
toward the center, overlapping on successive trips by 1/2 the rear
wheel of the roller. All rollers shall be of a type acceptable to
the Town's engineer. Rollers shall be operated at a speed satisfactory
to the Town's engineer, but not to exceed three miles per hour. Rolling
shall proceed continuously. Wheels of the roller and of the paver
shall be kept clean at all times. They may be kept moist with water
or a mixture of water with not more than 10% lubricating oil, as directed.
Dirty water, petroleum solvents or grease shall not be allowed to
drop from the roller or paver onto the pavement.
(b)
If depressions remain after rolling, additional pavement mixture
shall be added at such points and firmly rolled into place. After
rolling has been completed, the surface of the course shall have the
required crown, density and thickness and shall be of the grade established
for the surface of the finished pavement. Any unsatisfactory areas
shall be removed and replaced with suitable material.
A.
Gutters.
[Amended 12-12-1978]
(1)
In general, gutters shall not exceed 300 feet in length to a point
of discharge.
(2)
Where required, paved gutters shall be constructed on grades of 5%
or more with asphaltic concrete or Portland cement concrete, laid
on a six-inch compacted bank gravel base. The Portland cement concrete
shall have a minimum thickness of three inches and the asphaltic concrete
shall be a minimum of three inches thick after compaction.
(3)
Gutters shall be paved integral with road binder and top course.
(4)
All runoffs shall be paved with asphaltic concrete, a minimum thickness
of three inches after compaction, and shall extend the full length
of the slope.
B.
Culverts and storm drains.
(1)
Pipes of sufficient size and capacity shall be located where necessary
to provide adequate drainage without ponding.
(2)
Pipes.
[Amended 12-12-1978]
(a)
Pipes for all culverts shall be fully asphalt-coated helically
corrugated steel pipe. Corrugated steel pipe shall conform to the
requirements of AASHTO designation M-36. Pipe shall be helically corrugated
with all pipe seams continuously welded. On each pipe end there shall
be two rolled annular corrugations to facilitate band connection.
Pipe and connecting bands shall be plain galvanized in accordance
with AASHTO designation M-36. Connecting bands shall be 0.064 inch
thick minimum, and shall be the hugger band type or the annular corrugated
band type. Connecting bands must engage each pipe end with at least
one matching annular corrugation. Dimple bands, flat bands, helical
bands, etc., are not acceptable. Pipe shall be of the following minimum
gauges:
Pipe Diameter
(inches)
|
Gauge
| |
---|---|---|
15 to 24
|
16
| |
30
|
14
| |
36 to 48
|
12
| |
Over 48
|
10
|
(b)
Minimum pipe diameter shall be 15 inches. All culverts shall
have a minimum cover of 18 inches. Culvert pipes shall extend to the
toe of the embankment. All culverts shall be laid on a firm earth
foundation which shall have been carefully shaped to line and grade.
(3)
Materials used in bedding and backfill shall be select materials
from the on-site excavation. Backfill material shall be placed on
both sides of the culvert or structure at the same time in equal approximately
horizontal layers not exceeding eight inches in thickness before compaction
and thoroughly compacted with an approved mechanical tamper of the
whacker type to a subgrade level and shaped to receive other materials
specified. The equipment used for compaction must be in good working
order and subject to the approval of the Engineer. For compaction
equipment in good working order, the Engineer may consider the manufacturer's
recommendations or the results of actual field tests and allow an
increase in thickness of uncompacted backfill, not exceeding 12 inches,
based on the nature and moisture of the material to be compacted and
the number of passes to be made with the compactor. A minimum dry
density of 95% of the maximum density, which is the maximum dry weight
in pounds per cubic foot as determined by the AASHTO Designation T-99,
Method C, will be required. The contractor shall exercise special
care in placing and compacting material immediately adjacent to pipe
to avoid damage to a culvert or structure, or its alignment, regardless
of cause, shall be replaced. Any material backfilled and/or compacted
which does not comply with these specifications shall be removed and
replaced.
[Amended 12-12-1978]
(4)
All excess mortar and debris shall be removed from the inside of
the pipe, and the pipe shall be left in a clean, satisfactory working
condition.
(5)
Storm drains discharging into streams or ponds shall maintain the
invert at least one foot above normal high water mark. Velocity dissipation
structures shall be provided at all culvert discharges.
[Amended 12-12-1978]
C.
Headwalls.
(1)
At the inlet and discharge ends of culverts in embankments and the
terminus of stormwater drains, a headwall shall be constructed to
protect against erosion, unless catch basins or other drainage structures
are required according to the design.
(2)
Headwalls shall be built of rubble stone masonry or first class concrete,
with a top width of 18 inches and the rear face battered 1:4 as shown
on the construction standards. The minimum length shall be six feet.
The top elevation shall equal the ground surface and the bottom elevation
shall be a minimum of 30 inches below the pipe invert.
(3)
Concrete headwalls shall be constructed of one-to-two-to-four concrete
as shown on the construction standards.
(4)
Rubble stone masonry headwalls shall be built of clean stone, free
from structural defects, laid in full cement mortar beds of one part
Portland cement and three parts mortar sand. Vertical joints shall
be flushed with mortar. Selected stone, roughly squared and pitched
to line, shall be used for the copings and ends of walls.
(5)
The stone shall be laid on its natural bed to form substantial masonry,
presenting a neat and finished appearance. Spalls and pinners shall
not be allowed to show on the face of the wall and shall be used only
where necessary. All stones shall be laid to break joints six inches
or more and to thoroughly bond the work.
D.
Catch basins.
(1)
At the inlet end of pipe drains or culverts in cut sections, a catch
basin shall be constructed having minimum interior dimensions of two
feet wide by three feet long. They shall be constructed on a base
eight inches in thickness of one-to-two-to-four concrete at such an
elevation that the floor of the basin is 18 inches below the elevation
of the lowest outlet pipe.
(2)
Side walls shall have a minimum thickness of eight inches and shall
be built of one-to-two-to-four concrete as specified for base, brick
in mortar or concrete block in mortar.
(3)
Brick or concrete block shall be laid in mortar consisting of one
part Portland cement and two parts mortar sand by a competent mason
in a workmanlike manner, and both interior and exterior walls shall
be plastered with the same mortar at least 1/4 inch thick.
(4)
All connecting pipes shall be built through the walls in a workmanlike
manner. A cast-iron grate shall be placed on top of the basin as shown
on the construction standards. Gutter inlets shall pass under the
cast-iron grate with a clearance of at least eight inches.
E.
Dry hydrants. Where dry hydrants are required, they shall be installed
in the manner prescribed by the Town Engineer.
F.
Guide posts. Guide posts shall be installed in all fill sections
where the difference in elevation between the point of shoulder and
the original ground surface exceeds four feet, at all culverts and
headwalls, as shown on the construction plans approved by the Planning
Board, and elsewhere where directed by the Superintendent of Highways.
They shall be of round, seasoned red cedar, cypress or black locust,
free from bark, at least six inches in diameter at the smaller end
and a minimum of six feet, four inches in length, placed at eight
feet on center, three feet clear of the pavement edge, set vertically
and beveled on top. Posts shall extend two feet, 10 inches above the
finished ground surface and given three coats of outside white paint
after installation.
G.
Street signs. At each intersection, street name signs shall be erected,
conforming in all respects with the style and design required by the
Superintendent of Highways. On all streets ending in culs-de-sac,
dead-end signs shall be erected conforming in all respects with style
and design as required by the Superintendent of Highways.
H.
Other structures. Retaining walls, box culverts, water mains, manholes,
bridges or other structures not mentioned in these specifications
shall be designed in accordance with the appropriate current issue
of the specifications of the American Association of State Highway
and Transportation Officials, subject to the approval of the Planning
Board.
[Amended 12-12-1978]
A.
All slopes, except rock cuts, and any disturbed areas related in
any way to roads being constructed shall be covered with at least
four inches of topsoil and seeded to provide a hardy grass, producing
a turf which will stabilize the slope and prevent erosion.
B.
If there is insufficient topsoil available from the road area, good-quality
topsoil shall be imported subject to Town regulations and ordinances
relating thereto.
All work shall be neatly cleaned up on completion and left in
an orderly condition.
All operations under these regulations shall be conducted between
the hours of 7:00 a.m. and 6:00 p.m., and there shall be no operations
on Sundays or holidays except in an emergency and then only on authority
given by the Town Engineer of the Town of Lewisboro. All operations
shall be conducted in such manner as not to be objectionable or deleterious
to the health or welfare of the community or surrounding property
owners.
[Added 12-12-1978]
A separate map showing the as-built location of road, culverts
and catch basins and all utilities shall be submitted to the Planning
Board. The road, drainage systems and sewer lines shall also be shown
in vertical as well as horizontal position.