Unless otherwise specified by the Borough, all work shall be
performed in accordance with New Jersey State Highway Department Standard
Specifications for Road and Bridge Construction — 1961,
as revised. These specifications shall govern the installation and
construction of improvements in all sections of a subdivision whose
final plats have not received formal Borough approval prior to the
effective date of this chapter and shall apply to all construction
work hereafter performed on previously approved final plats where
adherence to the new specifications will not impose unnecessary hardship
by reason of prior commencement of such construction, prior commitments
of contracts or prior delivery of materials.
A.
After the roadway site has been cleared, the Borough Engineer (hereinafter
referred to as the "Inspector"), together with the engineering representative
of the owner, shall make an analysis of the natural subsoil material
and subsoil drainage conditions by borings and soil analysis.
B.
On the basis of the analysis and determination of his professional judgment as to the minimum standards for fully satisfactory results, the Borough Engineer shall specify the requirements for subbase, subdrainage, roadway base and pavement among the alternatives below. Such requirements shall then be incorporated by the owner in the final cross sections, profiles and utility plans submitted by him to the Joint Land Use Board in accordance with §§ 190-27 and 190-28 of this chapter. The Borough Engineer shall also submit a written report as to the conformance of the final plans to the requirements he has specified.
(1)
If the natural subsoil contains 15% or less of material passing a
No. 200 sieve and has adequate subsurface drainage, the owner shall
be permitted to construct directly upon the graded natural subsoil
pavement of a kind hereinafter specified.
(2)
If the natural subsoil contains more than 15% of material passing
a No. 200 sieve and has adequate subsurface drainage, a subbase of
a thickness determined by the Engineer, but in no case less than six
inches thick, shall be constructed. The subbase shall be of road gravel
or similar material containing not more than 12% of material passing
a No. 200 sieve and shall be constructed in accordance with Division
2, Section 9, of the state specifications.
(3)
If the natural subbase contains more than 15% of material passing
a No. 200 sieve and does not have adequate subsurface drainage, underdrains
of such size, location and number, together with access facilities
as determined by the Engineer, shall be constructed in addition to
the required subbase. Such underdrains may be constructed longitudinally
on the side of the street and transverse to the street. Where constructed
in the center of the street, underdrains shall be located with a minimum
of 18 inches clearance from the sanitary sewer. The trench in which
underdrains specified for roadway subsurface drainage purposes are
laid shall be filled with crushed stone or washed pebbles from 3/8
inch to 3/4 inch in size for a minimum of six inches below, on both
sides of and above the pipe, and the balance of the trench from the
top of the stone or washed pebbles to the subbase shall be filled
with approved porous material for a width at least equal to the bottom
of the trench, with a two-inch layer of salt hay or untreated paper
being placed upon the top of the stone or washed pebbles. Underdrains
shall be Type F, constructed in accordance with Division 5, Section
1, of the state specifications.
A.
Materials.
(1)
Bituminous stabilized base course. Materials shall conform to the
requirements specified therefor in Section 2A of the Standard Specifications
of the New Jersey State Highway Department for Bituminous Stabilized
Base Course, stone mix, mix No. 1, except that the minimum bitumin
content shall be 5%.
(2)
Surface course. The paving material shall be FABC mix No. 5 as specified
in the New Jersey State Highway Department Standard Specifications,
except the minimum percentage of bitumen shall be 6%.
B.
Methods of construction.
(1)
Subgrade. Before construction of the pavement, the subgrade shall
be in a properly finished condition conforming to the proper line
and grade and free of any soft spots or other deficiencies. Not more
than 24 hours prior to commencing of operations on any subgrade, the
subgrade shall be tested by running a roller of a weight at least
equal to that to be used in the paving operation over the entire subgrade
area. When permitted by the Engineer, testing may be performed by
other equipment, such as loaded trucks. When in the opinion of the
Engineer or his representative the deformation of the subgrade under
such tests is excessive, the subdivider will be required to stabilize
the subgrade in a manner satisfactory to the Engineer. The subgrade
shall not be prepared during freezing weather or when frozen or when
it is unstable.
(2)
Bituminous stabilized base course. The method of construction indicated
for materials above shall be used. The base course shall be laid on
a properly prepared subgrade and shall consist of two equal courses
unless otherwise approved by the Borough Engineer. Upon completion
of base course construction, the contractor shall cut samples from
the pavement with a jackhammer, coring machine or other means suitable
to the Engineer. The sample shall be intact for the full thickness
of the base course and shall be of a size suitable to the Engineer.
At least one sample shall be cut for every 1,000 square yards of base
course. Where deficiencies in the required minimum thickness are noted,
at least two additional cores will be required to determine the extent
of such deficiency. The average thickness of the base course as determined
by any five or more samples representing continuous areas of pavement
shall be not less than five inches or six inches, and the minimum
thickness permitted at any location will be 4 1/2 inches or 5 1/2
inches. The deficiency shall be made up by increasing the thickness
of the surface course.
(3)
Surface course. Prior to placing of the surface course, the contractor
shall repair any defects in the base course. Where cracking or any
other type of failure has occurred in the base course, the contractor
shall completely remove the base course, stabilize the subgrade if
necessary and construct new base course. Where the deficiency involves
depressions or raveling in the surface of the base course, the repair
may be made by skin patching with a suitable bituminous material.
C.
For checking of gutter drainage, the subdivider shall supply sufficient
water at the high points of the streets and shall run said water into
the gutters in order to determine whether or not gutter grades are
satisfactory. Wherever puddles occur, he shall skin patch the base
course to achieve proper grades in the gutters. After repair of the
base course, a tack coat shall be applied as specified in Section
3.10 of the New Jersey State Highway Department Standard Specifications.
D.
In the event of any deficiency in the surface course, such as raveling,
depressions, cracking, etc., such deficiencies shall be repaired by
removing the surface course and replacing with new material.
E.
All equipment and methods of construction shall conform to the New
Jersey State Highway Department Standard Specifications of 1961, except
that only one roller may be used where the area to be paved is sufficiently
small, in the opinion of the Engineer, to make the second roller unnecessary.
A.
Materials. Curbs, sidewalks and aprons shall be constructed of portland
cement concrete prepared in accordance with Division 3, Section 12,
of the state specifications, except as modified by the following mixture
and construction specifications:
(1)
Mixture.
|
Mix No. 1
Curbs, Gutters and Streets
|
Mix No. 2
Sidewalks
| ||
|---|---|---|---|
|
Water-cement ratios (maximum gallons/bag)
|
5.5
|
6
| |
|
Cement content (minimum bags)
|
6.6
|
6
| |
|
Air content
|
6% ± 1%
|
6% ± 1%
| |
|
Aggregate size (inches)
|
3/4 -1
|
3/4 -1
| |
|
Slump (inches)
|
3 ± 1
|
3 ± 1
| |
|
Fine aggregate (maximum)
|
40%
|
40%
| |
|
Strength (pounds per square inch)
|
4,200
|
3,750
|
(2)
Joint filler shall be cellular compression material conforming to
the requirements therefor of the Standard Specifications of the New
Jersey State Highway Department, as amended and revised to date.
B.
Methods of construction.
(1)
The contractor shall make all necessary excavations or embankments
for the construction and dispose of surplus materials. No filling
shall be done below the proposed curb or gutter except when absolutely
necessary, in which case such fill shall be made with clean sand or
approved gravel and thoroughly tamped before concrete is laid thereon.
All soft spots shall be thoroughly tamped or, if necessary, soft or
spongy material shall be removed and clean sand or approved gravel
refilled in its place.[1]
(2)
Backfill for curb. Within 72 hours after curbing is completed and
forms removed, the contractor shall backfill to the top of the curb
in back and to the established gutter grade in front. Backfill shall
be made with the materials excavated, except that any large or frozen
lumps, wood, boulders or other foreign matter shall be removed before
placing. Backfill shall be thoroughly compacted.
(3)
Forms. Forms for concrete may be of lumber or steel. They shall be
straight and of sufficient strength to prevent warping or bulging
and to retain the concrete accurately in position. All mortar and
dirt shall be removed from forms which have been previously used.
Forms shall be well staked to the proposed lines and grades, and their
upper edges shall conform to the finished surface of the curb. All
forms shall be thoroughly wetted immediately before concrete is deposited
against them.
(4)
Concrete. Concrete construction, including curing, shall conform
to the applicable requirements of the section on concrete structures
contained elsewhere herein.[2] The concrete shall be tamped and spaded or vibrated so
that the forms are completely filled, the concrete is thoroughly compacted
and mortar is flush with the face and top.
(5)
Joints.
(a)
Concrete curbs and gutters. Expansion joints shall be provided
at intervals of 20 feet or when new construction abuts existing construction.
The expansion joints shall be filled with 1/2 inch of thick cellular
compression material to within 1/2 inch of the top and face of the
curb and to within 1/4 inch of the top of the gutter. Dummy joints
shall be provided at alternate twenty-foot intervals.
(b)
Concrete sidewalks and aprons. Expansion joints 1/2 inch wide
shall be provided at intervals of 20 feet where the new paving abuts
curb or old work. The expansion joints shall be filled with 1/2 inch
of thick cellular compression material to within 1/4 inch of the top
of the paving. For sidewalks, surface grooves shall be cut with an
approved tool at least 1/4 inch thick at right angles to the line
of the sidewalk and at intervals equal to the width of the sidewalk.
Where new work abuts existing sidewalk, the surface grooves shall
be spaced to conform to the lines of the abutting walk. All surface
edges shall be rounded to a radius of 1/2 inch.
(6)
Curb finish. Before initial set, the top of the curb and the gutter
shall be finished with a wood float to an even, smooth, dense surface.
As soon as the forms can be removed, the face of the curb shall be
given the same finish. Exposed edges shall be neatly rounded to a
radius of 1/2 inch. The finished curb shall be true to the required
grades, lines, dimensions and curvatures. Completed work shall be
protected from traffic and the elements and shall be thoroughly wetted
and kept moist for at least one day. Damaged, broken or cracked work
shall be renewed by the contractor at his own sole cost and expense.
(7)
Concrete sidewalk and apron finish. The finish shall be with a wood
float, followed by brooming to a neat and workmanlike surface. Exposed
edges shall be neatly rounded to a radius of 1/2 inch. The concrete
shall be cured as provided elsewhere herein. The sidewalk and grass
shall slope at a rate of 1/4 inch per foot toward top of curbline
except as otherwise amended by the Borough Engineer.
(8)
Concrete work in cold weather. No concrete shall be poured between
December 1 and March 1 of each year without the prior expressed written
permission of the Engineer. Where such written permission is obtained,
the Engineer shall specify the appropriate procedures to be followed
from the state specifications, whose requirements shall also apply
from March to November in cold weather conditions.
(9)
Concrete curbs. Concrete curbs shall be constructed in accordance
with Division 5, Section 5, of the state specifications, except that
the mixture shall be as designated in these specifications. True joints
shall be placed on curb at twenty-foot intervals. Backfilling for
curbs shall be made within 72 hours after construction. Curb dimensions
shall be six inches wide at the top, nine inches wide at the bottom
and 18 inches deep. Unless otherwise required by the Engineer, the
reveal shall be six inches except at driveways, where a two-inch reveal
shall be used. Where the curb is to be constructed along lines having
a radius of 250 feet or less, securely anchored curved forms shall
be used. Multiple ten-foot-long tangent straight forms will be permitted
for curved curbs where the radius exceeds 250 feet, provided that
the ends of the tangents are finished to prevent the appearance of
sharp angles. At street intersections, the curb corners shall have
a minimum radius of 25 feet unless conditions are such that minimum
radius of 25 feet is not practicable. Where such conditions may occur,
the owners shall obtain written permission from the Engineer to decrease
the radius.
A.
Materials.
(1)
Cement used shall conform to the following requirements of ASTM as
amended to date:
(2)
Aggregate, both fine and coarse, shall conform to the requirements
therefor of the New Jersey State Highway Department Standard Specifications,
as amended and revised to date.
(3)
Water shall be clean, fresh and free of oils, acids, salts, organic
matter or other injurious substances. Unless otherwise provided, all
concrete shall be air-entrained, having 4% to 7% of entrained air,
and shall be produced by using standard portland cement with or without
additional additive as may be required.
(4)
Reinforcing steel shall be intermediate grade deformed bars conforming
to ASTM Designation A-15 and ASTM Designation A-432, as amended and
revised to date.
B.
Methods of construction.
(1)
The Engineer will determine the slump ranges within which the contractor
must work. Ready-mix or transit-mix concrete may be used if obtained
from sources approved by the Engineer. Equipment used to proportion
and mix concrete on the job is subject to the approval of the Engineer.
(2)
Forms shall conform to the shape, lines, dimensions and grades shown
on the plans. They shall be firmly braced, tight and substantial so
as to prevent movement, bulging and mortar leakage. Wherever concrete
will be exposed to view, forms shall be smooth and clean.
(3)
Forms for footings may be omitted wherever soil and workmanship permit
accurate excavation to the size required. All forms shall be completely
removed.
(4)
Reinforcements shall be accurately cut, bent and placed in accordance
with the plans. They shall be free of excessive scale or any foreign
material that would tend to reduce bond. They shall be securely supported,
tied and fastened to prevent movement while concrete is being placed.
(5)
Subgrades, excavations and soil bases for foundations and slabs shall
be properly finished to the prescribed lines, grades and dimensions
and shall be approved by the Engineer before concrete is placed. All
areas to receive concrete shall be free of frost, foreign matter and
excessive water; provided, however, that forms and soil surfaces shall
be uniformly damp when the concrete is placed.
(6)
Concrete shall be handled and placed so as to avoid any segregation.
Concrete which has begun to set or which has been contaminated with
foreign materials or to which too much water has been added shall
not be used. Pouring of concrete shall generally be a continuous operation
until the placing of an individual section has been completed. Concrete
shall be thoroughly compacted with vibrators or by other suitable
means.
(7)
All concrete shall be finished by screeding and floating to the required
lines and grades. Unless otherwise specified, all work shall have
a wood float finish; provided, however, that the contractor shall
provide other finishes when so required by the plans or specifications
or so directed by the Engineer.
(8)
After the concrete has been poured, it shall be kept continuously
set for a period of one day or longer as directed by the Engineer.
Curing compound may be substituted for water, but in all cases curing
shall be done in a manner approved by the Engineer.
(9)
Expansion joints, dummy joints, construction joints and other appurtenances
shall be provided as shown on the plans. Expansion joints shall have
joint filler of the thickness indicated, which shall extend the full
depth of the concrete.
(10)
After removal of forms, all permanently exposed surfaces shall
be cleaned of stains and dirt, and all surface defects which do not
impair structural strength shall be repaired by cutting and patching
in a manner satisfactory to the Engineer.
(11)
Concrete shall not be poured when the atmospheric temperature
is below 40° F. or when there is any precipitation, unless precautions
satisfactory to the Engineer have been taken to prevent any damage
to the work. Precautions necessary to avoid freezing of the concrete
shall be in accordance with the current recommendations of the American
Concrete Institute.
Fire hydrants shall be as manufactured by the Kennedy or Mueller
Valve Company or other type approved by the Fire Marshal. Operating
and cap nuts shall be one-and-one-half-inch pentagon. They shall be
equipped with two hose nozzles and one steamer nozzle, size and threads
to be in accordance with local fire company requirements. They shall
have a provision for six-inch connection to the main. Minimum valve
opening for the hydrant shall be 4 1/4 inches.
A.
Materials.
(1)
Cast-iron pipe and fittings. Cast-iron pipe shall be centrifugally
cast cement lined and shall conform to the requirements of the American
Standards Association specifications therefor, as amended and revised
to date. In general, cast-iron pipe shall be thickness Class 22 for
nominal pipe diameters of 12 inches and less and Class B for sizes
14 inches and greater. Cast-iron saddles shall be subject to the approval
of the Borough Engineer.
(2)
Asbestos-cement pipe and fittings. Asbestos-cement pipe and fittings
shall conform to the requirements of the American Society for Testing
and Materials specifications therefor, as amended and revised to date.
Except where required for special conditions such as excessive depth,
asbestos-cement pipe and fittings shall be nonpressure and in no case
less than Class 2400. All asbestos-cement pipe and fittings shall
be furnished complete with sleeve and gasket-type couplings designed
for use with the size and class of pipe specified.
(3)
Vitrified clay pipe and fittings. Vitrified clay pipe and fittings
shall conform to the requirements of the American Society for Testing
and Materials specifications therefor, as amended and revised to date.
Except where required for special conditions such as excessive depth,
vitrified clay pipe and fittings shall be extra-strength or Vitra-Chem.
All vitrified clay pipe and fittings shall have factory-fabricated
gasket-type couplings with O-ring joints which conform to the American
Society for Testing and Materials specifications therefor, as amended
and revised to date.
(4)
Concrete. Any concrete required for cradles, pads, drop connections
at manholes and any other miscellaneous items shall be 4,000 pounds
per square inch conforming to the requirements set forth elsewhere
herein.
B.
Methods of construction.
(1)
Excavation and backfill shall conform to the requirements set forth
for subsurface structure excavation. The contractor shall provide
adequate equipment and so operate it as to maintain an essentially
dry excavation, stable trench bottoms, suitable working conditions
and protection from water damage throughout and until the completion
of the work.
(2)
Pipe shall be laid in straight lines between manholes except when
otherwise specifically provided or directed by the Engineer. When
deviation from a straight line is permitted, the deflection of each
joint shall not exceed the manufacturer's recommended maximum
for the type of joint and size of pipe being installed. All pipe shall
be laid to uniform grades between manholes.
(3)
Before making each joint, the ends of the pipes and all joint members
shall be thoroughly cleaned. All jointing shall be done in strict
accordance with the manufacturer's recommendations and directions
of the Engineer.
(4)
No defective or leaking pipe, fittings, joints, connection, manholes
or other parts of the work will be acceptable. All visible leakage
of any description, no matter where located, shall be corrected by
the contractor in a manner satisfactory to the Engineer, whether or
not the total leakage into the sewer is within the allowable maximum
as determined by infiltration tests. Internal inspection by the Borough
Television Inspection Unit shall be made after heavy construction
traffic has ceased and before top course of FABC is installed.
(5)
Infiltration tests shall be made when and as directed by the Engineer,
and no connections to flowing lines shall be made until the testing
is complete and satisfactory results have been obtained. The contractor
shall furnish all labor, material and equipment necessary for the
infiltration tests.
(6)
No section of sanitary sewer between adjacent manholes will be considered
satisfactory or acceptable when the rate of infiltration thereinto
exceeds 100 gallons per inch of internal diameter per mile of sewer
per day, and no section of sanitary sewer one mile or more in length
will be considered satisfactory or acceptable when the rate of infiltration
thereinto exceeds 1/2 of the above specified rate. Leakage in excess
of the above shall be located and corrected by the contractor. Where
deemed necessary by the Borough Engineer, exfiltration tests by use
of air or water may be required in lieu of infiltration tests.
(7)
Y-branches and service laterals which are not to be immediately connected
to flowing lines shall be securely plugged with an approved type of
plug which will provide a permanently watertight seal.
(8)
The contractor shall accurately record the station of each Y-branch
placed and the direction of the Y. He shall also show the location
of each Y-branch on his copy of the plans and permanently mark each
location with a crosscut on the curb or a hub stake driven at the
curbline.
(9)
Drop connections at manholes and concrete pads at service risers
shall be constructed as shown on the detail sheet of the plans and
at the locations shown on the plans or as directed by the Engineer.
All concrete work shall conform to the requirements as set forth elsewhere
herein.
(10)
When so required by the Engineer, the contractor shall flush
such newly completed sewers as may be designated by the Engineer in
order to remove any foreign matter which may have accumulated therein
during construction. The contractor shall furnish all labor, material,
equipment and water necessary for flushing and shall provide for the
disposal of water used for flushing.
A.
Materials.
(1)
Reinforced concrete pipe. Reinforced concrete pipe shall conform
to the requirements of the American Society for Testing and Materials
specifications therefor, as amended and revised to date. Unless otherwise
specified herein, reinforced concrete pipe shall be Class III, Wall
B.
(2)
Corrugated metal pipe.
(a)
Corrugated metal pipe and pipe arch shall conform to the requirements
of the American Association of State Highway Officials specifications
therefor, as amended and revised to date, and conform to the following
gauge requirements:
|
Diameter
(inches)
|
Gauge
(aluminum)
|
Gauge
(corrugated)
| |
|---|---|---|---|
|
15
|
14
|
16
| |
|
18
|
12
|
16
| |
|
21
|
12
|
16
| |
|
24
|
12
|
14
| |
|
30
|
12
|
14
| |
|
36
|
10
|
12
| |
|
42
|
10
|
12
| |
|
48
|
10
|
10
| |
|
54
|
8
|
10
| |
|
60
|
8
|
8
|
(b)
For pipe diameters in excess of 60 inches, the specific design
shall be approved by the Engineer.
(c)
Corrugated metal pipe and pipe arch shall be fully bituminous-coated
inside and outside in accordance with current American Railway Engineering
Association specifications and shall have bituminous paved inverts.
The invert paving shall fill the valleys of the corrugations a minimum
of 1/8 inch. For round pipe the invert shall cover not less than 25%
of the inside perimeter of the pipe, and for pipe arch the invert
paving shall cover not less than 40% of the inside perimeter of the
pipe. Corrugated metal pipe shall be permitted only by specified written
approval of the Borough Engineer.
(3)
Concrete. Concrete of a strength of 4,000 pounds per square inch
conforming to the requirements set forth elsewhere herein shall be
used for the construction of concrete cradles and in making connections
to existing drainage structures.
B.
Methods of construction.
(1)
Excavation and backfill shall conform to the requirements for subsurface
structure excavation. The contractor shall provide adequate equipment
and so operate it as to maintain an essentially dry excavation, stable
trench bottoms, suitable working conditions and protection from water
damage throughout and until the completion of the work.
(2)
Pipe shall be laid in straight lines between drainage structures
except when otherwise specifically provided. When deviation from a
straight line is permitted, the deflection of each joint shall not
exceed the manufacturer's recommended maximum for the type of
joint and size of pipe being installed. All pipe shall be laid to
uniform grades.
(3)
Each section of pipe shall be solidly bedded in the trench bottom
and shall be supported for its full length except where excess excavation
has been made for joints. Before making each joint, the ends of the
pipes and all joint members shall be thoroughly cleaned. All jointing
shall be done in strict accordance with the manufacturer's recommendations.
(4)
No defective or leaking pipe, joints, connections, manholes, inlets
or other parts of the work will be acceptable. All visible leakage
of any description, no matter where located, shall be corrected by
the contractor in a manner satisfactory to the Engineer.
(5)
Except when necessary to maintain a flow, storm drains shall not
be placed in embankment until the embankment has been constructed
and consolidated to proposed finished grade or subgrade or to an elevation
not less than three feet above the proposed top of pipe, whichever
is lower. After an embankment has been so constructed, trenches for
storm drainage shall be excavated as hereinabove specified.
(6)
When so required by the Engineer, the contractor shall flush such
newly completed drains as may be designated by the Engineer in order
to remove any foreign matter which may have accumulated therein during
construction.
(7)
The contractor shall furnish all labor, material, equipment and water
necessary for flushing and shall provide for the disposal of water
used for flushing.
(8)
The locations of existing pipes and structures shown on the plans
are approximate, and before construction the contractor shall determine
the exact locations of all existing pipes and structures in the vicinity
of the proposed work. Connections to existing pipes and structures
shall be made in a manner satisfactory to the Engineer.
A.
Materials.
(1)
Concrete. Concrete shall conform to the requirements specified elsewhere
herein.
(2)
Concrete block. Concrete block for the construction of manholes,
inlets and catch basins shall conform to the requirements of the American
Society for Testing and Materials specifications therefor, as amended
and revised to date. Concrete blocks for manholes shall have the required
radius and batter.
(3)
Brick. Brick shall be Grade MA, conforming to the American Society
for Testing and Materials specifications therefor, as amended and
revised to date.
(4)
Mortar. Mortar shall be one-to-two cement and mortar.
(5)
Iron castings. Iron castings shall conform to the requirements of
the American Society for Testing and Materials specifications for
gray iron casting, as amended and revised to date, supplemented as
follows: castings shall have to be boldly filleted and risers shall
be sharp and perfect. The castings shall be true to pattern in form
and dimension, free of pouring faults, sponginess, cracks, blowholes
and other defects which affect their strength and value for the service
intended. The bearing surfaces of frames, covers and grates shall
be fitted together so as to prevent rocking and the pieces matchmarked.
(6)
Ladder rungs. Ladder rungs shall be fabricated of rolled wrought
iron or aluminum conforming to the current American Society for Testing
and Materials specifications therefor and shall be subject to the
approval of the Engineer.
B.
Methods of construction.
(1)
Excavation and backfill shall conform to the requirements of subsurface
structure excavation. Manholes, inlets and catch basins shall be constructed
in accordance with the standard details shown on the plans. Unless
otherwise specified or directed, manholes, inlets and catch basins
may be constructed of either brick, concrete block or concrete of
a strength of 3,000 pounds per square inch.
(2)
Concrete construction shall conform to applicable requirements elsewhere
herein.
(3)
Concrete blocks and bricks shall be laid with vertical joints staggered.
Joints shall be not more than 1/2 inch thick and shall be completely
filled with mortar. The masonry shall be carried to such a height
that a mortar joint not more than 1/2 inch thick will be required
for setting the head casting without using split blocks or bricks.
Outside walls shall be plastered with a five-eighths-inch-thick coat
of mortar, troweled to a smooth finish. Inside walls shall have wiped
joints.
(4)
Outside walls of sanitary sewer manholes shall receive two coats
of an approved coal-tar pitch.
A.
Materials.
(1)
Material for backfill, if acceptable to the Engineer or his representative,
shall be the material excavated, except that any large and frozen
lumps, wood, boulders or other foreign matter shall be removed before
placing.
(2)
If the excavated material is not acceptable as backfill material,
all excavations shall be backfilled with run-of-bank sand or gravel.
All excess excavated material will be disposed of by the contractor
in a manner acceptable to the Engineer.
B.
Methods of construction.
(1)
The contractor shall do all excavation of whatever substances encountered
to the depth shown on the plans.
(2)
Excavation shall not be carried below the required level except where
unstable soil is encountered. The Engineer shall determine the depth
of removal of unstable soil, and the contractor shall, at the Engineer's
direction, remove and replace the same with gravel, crushed stone
or crushed slag thoroughly tamped. Whenever excavation has been made
below the required level, it shall be replaced with gravel, crushed
stone or crushed slag, which shall be thoroughly tamped.
(3)
Ground adjacent to the excavations shall be graded to prevent water
from running in. The contractor shall remove any water accumulating
in excavations by pumping or other suitable means.
(4)
The contractor shall do all bracing, shoring and sheeting necessary
to prevent failure of the banks of the excavation and to protect the
work, workmen, public, underground and aboveground utilities and structures,
pavements and public and private property. No bracing, shoring or
sheeting shall be placed below the bottom of the pipe or structure
unless approved by the Engineer.
(5)
The contractor shall provide, install and operate an adequate well-point
system of dewatering when necessary to stabilize trench bottoms and
banks or other excavations or when necessary to protect the work,
workmen, public, underground and aboveground utilities and structures,
pavements and public and private property. The well-point system or
portions thereof shall be removed by the contractor upon completion
of backfill, and the holes remaining from the points shall be backfilled
and thoroughly tamped.
(6)
Excavations for manholes and other structures shall have a twelve-inch
minimum clearance and twenty-four-inch maximum clearance on all sides.
The width of trenches for pipes shall not be less than 16 inches and
not more than 22 inches in excess of the outside diameter of the pipe.
Rocks and boulders present in excavations shall be removed within
six inches of the pipe. Banks of excavation, unless otherwise indicated
or allowed, shall be vertical.
(7)
Preliminary excavation shall be made only to a depth of three inches
above the final depth of any trench or other excavation. The remaining
depth shall be carefully excavated, shaped and formed with hand tools
immediately preceding laying of pipe or placing concrete. Trench bottoms
shall be accurately formed to receive and support the bottom of the
barrel of the pipe. Additional excavation shall be made in pipe trenches
at the pipe joints and to prevent any possibility of a pipe resting
on the bell rather than the barrel.
(8)
After the structure has been completed, inspected and approved or,
in the case of pipe, after each joint has been made, inspected and
approved, backfilling shall proceed immediately. Where pipe has been
laid, this shall be done in four-inch layers of suitable fine material,
each layer thoroughly tamped, to a height of 12 inches above the top
of the pipe. The remainder of the trench and the entire excavation
for all structures other than pipe shall be backfilled in nine-inch
layers, loose measure, each layer thoroughly tamped. Dampening of
the material to be tamped may be required by the Engineer.
(9)
Puddling or flushing in lieu of tamping may be used if approved by
the Engineer or may be required by the Engineer. Shoring, sheeting
and bracing of any kind shall be withdrawn as the backfilling proceeds,
except that the Engineer may require such bracing to be left in place
if it has been placed below the bottom of any structure or pipe or
if he deems it necessary in order to protect adjacent structures,
utilities or property.
