SECTION 17
CURB AND GUTTER
17.1
GENERAL: Unless otherwise shown on the plans or approved by
the City Engineer, all curb and gutter shall be Type ‘B’ Curb and
Gutter per Logan City Standard Drawing VI-17-1.
17.2
EXCAVATION FOR CURB AND GUTTER:
All excavation and
preparation of sub-grade required for construction of concrete curb
and gutter and reinforced concrete drain gutter shall be done as
provided in all applicable provisions of Section 10.3 of these
specifications, as determined by the Engineer. Embankment required
under the concrete shall be with approved material compacted to 95%
of maximum density.
17.3
CONSTRUCTION:
Concrete curb and gutter and reinforced
concrete drain gutter shall be constructed in conformity with the
lines, grades, slopes, form and dimensions shown on the plans or as
designated by the Engineer. In the construction of combined curb
and gutter, the entire structure shall be built simultaneously and
no joint or line of cleavage shall be made between the curb and the
gutter.
The type of curb and gutter will be Type B unless
otherwise shown on plans or as designed by the City Engineer. See
Standard Drawing VI-17-7.
17.4 CLASS OF CONCRETE: The concrete used for the construction of
reinforced concrete drain gutter and concrete curb and gutter shall
be "Class B," air entrained using type II cement as per
Section 12.3.
17.5 JOINTS: At intervals of ten feet, joints shall be made by
inserting iron plates one-eighth inch in thickness and shaped to
the exact form and dimensions of the curb gutter. Plates must be
smooth and clean. They shall be oiled with mineral oil immediately
before using. Any plate that has become warped or damaged shall
not be used. They shall be carefully removed after the concrete
has set, and any concrete broken out shall be repaired to the
satisfaction of the Engineer.
A.
At the contractors option, plates a minimum of 2" deep
may substituted for the full depth plates at contraction
joints only.
A full plate must be used at expansion
joints and ends of the constructed section, such as at
driveways, curved sections and or where determined by the
Engineer.
B.
After division plates have been removed and joints have
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been properly set, then the concrete shall be sealed in a
manner and with material approved by the Engineer.
17.6 MODIFY CURB AND GUTTER IN DRIVEWAYS: At driveways other than
single family residential driveways, or Accessory Dwelling Unit
driveways such as duplex and larger dwelling units, service
stations and all driveways used for commercial and industrial
traffic, the thickness of the gutter through the entire driveway
shall be as shown on the drawing, or as determined by the Engineer,
but in no case shall the thickness of the concrete gutter be less
than eight inches.
The transition areas for curb & gutter at driveway openings and
radius corners shall conform to Uniform Federal Accessibility
Standards Section 4.7. In addition, if the sidewalk is adjacent to
the curb and gutter, the length of the transition shall be a
minimum of 5 feet. If the sidewalk is not adjacent to the curb and
gutter, the length of the transition shall be a minimum of 4 feet.
Driveways shall be flared type driveways with curb cuts instead of
radius unless otherwise approved by the City Engineer. The minimum
width of a driveway shall be 12 feet, exclusive of the curb
transitions at either side. See City of Logan Land Development
Code, Section 17.37 for other requirements for driveways.
Flared type driveways may be created in existing curb and gutter by
(1) removing and replacing the existing curb and gutter, or (2) by
saw cutting the back of the curb. If saw cutting is used, IT SHALL
BE CUT FROM THE BACK OF THE CURB TO THE FLOWLINE, NOT FROM THE
FRONT.
17.7 PLACING, COMPACTION, AND CURING:
The method of mixing,
placing, compacting, finishing and curing, etc., of the concrete
shall conform to all applicable requirements of Section 12 of these
specifications, and as determined by the Engineer.
A.
Curb and gutter may be placed by an approved slip form
method. The slip form machine equipment shall spread,
consolidate, screed and float finish the freshly placed
concrete in such a manner that a minimum of hand float
finishing will be required to provide a dense and
homogeneous concrete section.
The concrete shall be distributed uniformly into final
position by the machine without delay and competently
placed true to line and grade.
The contraction joints every ten feet will be provided by
cutting into the fresh concrete to a minimum depth of 1
1/2 inches to create a weakened vertical plane.
The
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edges of such joints shall be tooled with an edger so as
to provide a neat workmanlike appearance.
Expansion
joints will not be required except at adjacent pavement,
walk or structure.
This option shall be so noted in the bid schedule, by the
contractor when this alternate is used in bidding this
item.
B.
Straight sections of curb and gutter may be placed in
metal forms. After concrete has been placed in the curb
and gutter forms, it shall be paddled and spaded so as to
insure a thorough mixture, eliminate air pockets, and
create uniform and smooth sides. Before the concrete has
thoroughly set, and while the concrete is still green,
the forms shall be removed and the front and top sides
shall be finished with a flat or magnesium float
trowel to make a uniform finished surface.
Wherever
corners are to be rounded, special steel trowels may be
used while the concrete is workable and the corners
constructed to the dimensions specified.
The top and face of the curb and also the top of the
apron on combined curb and gutter must be finished true
to line and grade and without any irregularities of
surface noticeable to the eye. The gutter shall not pond
water to a depth of more than one fourth of an inch, nor
shall any portion of the surface or face of the curb and
gutter depart more than one fourth of an inch from a
straight edge ten feet in length, placed on the curb
parallel to the center line of the street nor shall any
part of the exposed surface present a wavy appearance.
17.8 UTILITY LINE AND PROPERTY LINE MARKER:
In new curb and
gutter, or in existing curb and gutter when new water or sewer
service lines or laterals are installed, an approved curb marker
shall be installed in the top of the curb over the service line or
lateral and shall be marked “water” or “sewer”.
17.9 REINFORCED CONCRETE DRAIN GUTTER: The reinforced concrete
drain gutter shall be constructed with the adjoining gutters and
shall consist of concrete minimum eight inches in thickness, unless
otherwise shown, and reinforced longitudinally, and shall be built
to conform to dimensions, form and to elevations as shown on the
plans or as directed by the Engineer.
The concrete used shall be "Class B," the same as provided in
Section 12.3 of these Standards and Specifications.
The methods of placing, compacting, finishing and curing, as
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provided in Section 12 of these Specifications shall apply to the
construction of the drain gutter.
Where necessary, in the opinion of the Engineer, gravel shall be
placed and thoroughly compacted to form a base for the drain
gutter, as directed by the Engineer.
17.10
PROTECTION:
The Contractor shall protect all curb and
gutter and drain gutter from damage from traffic and all other
causes until accepted by the City. Should the curb and gutter or
drain gutter become damaged by weather, traffic, or during work in
the street, or from any other cause, it shall be repaired by
reconstructing an entire section, by and at the expense of the
Contractor, and to the satisfaction of the Engineer.
17.11 CONCRETING IN COLD WEATHER: See section 12.9.
17.12 CURB RETURNS TO MEET A.D.A REQUIREMENTS: The transition
areas for sidewalks and for curbs at driveway openings and radius
corners shall conform to the latest standards for ADA Access Ramps
as described in this manual or as required in Special Provisions
for the project.
This shall include the construction and/or
installation of Truncated Domes at each ramp. Installation and
application shall be approved by the City Engineer before the
construction or installation or application takes place. See also
Standard Drawing VI-16-01 for curb returns.
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