PART 1 GENERAL
1.01 DESCRIPTION:
A. Provide
concrete curbs, walks, and paving as shown and specified. The work includes:
Subgrade preparation and paving
base.
1. Curbing and walks.
B. RELATED
WORK:
Section 02000: Site Work.
2. Section 02100: Site Preparation.
3. Section 02200: Earthwork.
4. Section 02400: Site Drainage.
5. Section 03200: Concrete Reinforcement.
6. Section 03300: Cast-in-Place Concrete.
1.02 QUALITY
ASSURANCE:
A. Comply with Section 02000
requirements.
B. Testing and inspection: Performed
by a qualified independent testing laboratory.
C. Provide and pay for testing and
inspection during concrete operations. Laboratory shall be acceptable to the
Landscape Architect.
D. Materials and methods of
construction shall comply with the following standards:
American Society for Testing and
Materials, (ASTM).
American Concrete Institute,
(ACI).
Maintain field
records of time, date of placing, curing, and removal of forms of concrete in
each portion of work.
A. Do not change source or brands of
cement and aggregate materials during the course of the work.
Construct street and
access driveway curb cuts, entrance apron paving, curbs, and sidewalks in
accordance with City of Fargo standards.
1.03 SUBMITTALS:
A. Submit concrete mix designs. Obtain
approval before placing concrete.
B. Product data:
Submit complete materials list
of items proposed for the work. Identify materials source.
1. Submit admixture, curing compound, retarder, and
accessory item product data.
2. Submit material certificates for aggregates,
reinforcing, and joint fillers.
C. Mix by class or sack content with
maximum size aggregate.
D. Submit
list of any admixtures.
E. Submit
information on air content if used.
F. Slump
2" to 4".
G. Submit time of loading slips if
weather condition over 90 degrees F.
H. Submit
concrete test reports.
1.04 DELIVERY,
STORAGE, AND HANDLING:
Deliver curing materials, admixtures, and
retarders in manufacturer's standard unopened containers with labels legible
and intact. Store and protect from freezing and damage.
1.05 PROJECT
CONDITIONS:
A. Work notification: Notify Landscape
Architect at least 24 hours prior to installation of concrete.
B. Establish and maintain required
lines and grade elevations.
C. Do not install concrete work over
wet, saturated, muddy, or frozen subgrade.
D. Do not install concrete when air
temperature is below 32 degrees F. Use of calcium chloride, salt, or any other
admixture to prevent concrete from freezing is prohibited.
E. Protect adjacent work.
F. Provide temporary barricades and
warning lights as required for protection of project work and public safety.
PART 2 PRODUCT
2.01 MATERIALS:
A. Portland Cement: ASTM C150, Type 1,
natural color. Provide white Portland cement for integrally colored concrete.
B. Aggregate: Provide AASHTO M43
Grading #57 clean, uncoated crushed stone or gravel coarse aggregate free of
materials which cause staining or rust spots; fine aggregate shall be clean
natural sand.
C. Water: Clean, fresh, and potable.
D. Air-entraining admixture: ASTM
C260.
E. Water-reducing admixture: ASTM
C494.
2.02 MIXES:
A. Provide ASTM C94 ready-mixed
concrete. Batch mixing at site not acceptable.
B. Strength: 3,000 psi minimum at 28
days for curbs and 4,000 psi minimum for sidewalks.
C. Slump range: 2" to 4"
maximum.
D. Provide an approved water-reducing
admixture in all concrete.
E. Provide an air-entraining admixture
in all concrete. Air content 5% to 7%.
F. Indicate water added to mix at job site
on each delivery ticket. Show quantity of water added. Site water tempered
mixes exceeding specified slump range will be rejected as not complying with
specification requirements.
2.03 ACCESSORIES:
A. Granular base: AASHTO M43, #6
(3/8" to 3/4") uniformly graded, clean crushed stone or gravel.
Granular base: 4 to 6 inches for
sidewalk shown on drawings.
3. Granular base: 4 inches for curbs as shown on drawings.
B. Forms: Wood or metal of sufficient
strength to resist concrete placement pressure and to maintain horizontal and
vertical alignment during concrete placement. Provide forms straight, free of
defects and distortion, and height equal to full depth of concrete work.
Provide 2" nominal thickness, surfaced plank wood forms for straight sections.
Use flexible metal, 1" lumber or plywood forms to form radius bends.
C. Joint filler: ASTM D1752, premolded
resilient non-extruding non-staining closed cell foam polyethylene, PVC foam or
sponge rubber, 25% wider than joint width, thickness indicated.
D. Curing Compound: ASTM C309,
non-yellowing, non-staining liquid membrane forming type containing a fugitive
dye. Chlorinated rubber compounds not acceptable for exterior use.
E. Joint sealant: Two-component
polysulfide or polyurethane elastomeric type complying with FS TT-S-00227,
self-leveling, designed for foot traffic.
F. Reinforcing steel: ASTM A615, A616,
or A617, Grade 40, new domestic deformed steel bars.
G. Form release agent: Non-staining
chemical form release agent free of oils, waxes, and other materials harmful to
concrete.
PART 3 EXECUTION
3.01 INSPECTION:
Examine subgrades and installation conditions.
Do not start concrete work until unsatisfactory conditions are corrected.
3.02 PREPARATION:
A. Proof roll the subgrade and do all
necessary rolling and compacting to obtain firm, even subgrade surface. Fill
and consolidate depressed areas. Remove uncompactable materials, replace with
clean fill and compact to 100% of the maximum dry density in accordance with
ASTM D698 Standard Proctor Method.
B. Provide minimum 0'-6" depth of
compacted granular base material at walks and minimum 0'-4" depth at
curbing. Compact granular base to 95% of the maximum dry density in accordance
with ASTM D698 Standard Proctor Method.
Perform compacted granular base
as shown and specified.
C. Remove loose material and debris
from base surface before placing concrete.
D. Install, align, and level forms.
Stake and brace forms in place. Maintain following grade and alignment
tolerances:
Top of form: Maximum 1/8"
in 10'-0".
4. Vertical face: Maximum 1/4" in 10'-0".
E. Coat form surfaces in contact with
concrete with form release agent. Clean forms after each use and coat with form
release agent as necessary to assure separation from concrete without damage.
F. Locate, place, and support
reinforcement as indicated:
1. Provide a single layer of reinforcing bars at 24 inches
on center - both ways or as shown and specified in all concrete slabs-on-grade.
G. Provide reinforcing bars at curbs, and
other locations indicated, adequately supported and secured to prevent
displacement.
H. Install, set, and build-in work
furnished under other specification sections. Provide adequate notification for
installation of necessary items.
3.03 INSTALLATION:
A. Concrete
Placement:
Comply with ACI 304
"Recommended Practice for Measuring, Mixing, Transporting, and Placing
Concrete", and as specified.
Protect concrete from physical
damage or reduced strength due to weather extremes during mixing, placing, and
curing. In cold weather comply with ACI 306, "Recommended Practice for
Cold Weather Concreting". In hot weather comply with ACI 305,
"Recommended Practice for Hot Weather Concreting".
Moisten base to provide a
uniform dampened condition at the time concrete is placed. Verify manholes or
other structures are at required finish elevation and alignment before placing
concrete.
Place and spread concrete to the
full depth of the forms. Use only square-end shovels or concrete rakes for
hand-spreading and consolidating concrete. Exercise care during spreading and
consolidating operations to prevent segregation of aggregate and dislocation of
reinforcement.
Place concrete in a continuous
operation between expansion joints. Provide construction joints when sections
cannot be placed continuously.
Place concrete in one course,
monolithic construction, for the full width and depth of concrete work. Provide
minimum 5-inch thick paving, except as otherwise indicated or specified.
Provide 1-1/2" to 2" of coverage of all reinforcing bars (rebars).
5. Strike-off and bull-float concrete after consolidating.
Level ridges and fill voids. Check surface with a 10'-0" straightedge.
Fill depressions and refloat repaired areas. Darby the concrete surface to
provide a smooth level surface ready for finishing.
B. Provide curb profiles indicated.
C. Provide concrete base for patching
and repairing existing street paving which is damaged or removed to accommodate
new curbs, walks, and entrance apron paving.
D. Joints:
Construct control, expansion,
and construction joints properly aligned with face perpendicular to concrete
surface.
Provide tooled control joints,
sectioning concrete into areas indicated on drawings. Tool joints to depth
equal to not less than 3/4-inch. Hand tool control joints in pattern and at
spacing indicated. When not indicated, provide spacing equal to slab width and
not greater than 10'-0" on center.
Provide sawed control joints,
sectioning concrete into areas indicated. Saw joints to a depth equal to not
less than 3/4-inch and of maximum 1/4" width. Saw cut joints as soon as
surface is firm enough not to be torn or damaged by the cutting blade. Cut
joints in pattern and at spacing indicated. When not indicated, provide spacing
equal to slab width and not greater than 10'-0" on center.
Provide standard keyed-section
construction joints where new construction meets old concrete slabs, unless
otherwise indicated. These areas may also use a #5 rebar pinned connection at a
maximum of 1'-4" O.C.
Provide expansion joints using
premolded joint filler at concrete work abutting curbs, walls, structures,
walks, and other fixed objects.
Locate expansion joints as
indicated. When not indicated, provide joints
at maximum
30'-0" on center for curbs and walks. Align expansion joints
in abutting
curbs and walks.
Install joint fillers full-width
and depth of joint. Recess top edge below
finished where
joint sealant are indicated.
Provide joint fillers in single
lengths for the full slab width, whenever
possible. Fasten
joint filler sections together when multiple lengths are
required.
Protect the top edge of the
joint filler during concrete placement. Plastic
caps may be used
if removed promptly after concrete placement.
E. Concrete
Finishing:
Perform concrete finishing using
mechanical or hand methods as required.
Upon completion
of floating, and after bleed water has disappeared and
concrete can
sustain foot pressure with nominal indentation, cut concrete
away from forms.
Work edges with an edging tool. Round edges to 1/2"
radius. See
drawings for further instructions on concrete finish and patterns.
Install control joints at
indicated locations during edging operations.
6. Complete surface finish as follows:
Provide sidewalk
and pavement surfaces with a coarse broomed textured finish as per drawings.
Edge outside edges and all joints with a radius edging tool.
Ramps: Lightly
broadcast non-slip aggregate to provide a non-slip textured broomed finish.
a) Curbs: Provide a smooth float
finish.
F. Curing:
Cure concrete with a
non-staining liquid membrane-forming compound.
Spray apply in
accordance with manufacturer's recommended coverage
rate. Apply
curing compound immediately after completing surface
finish.
Wet cure concrete by application
of absorptive mats or fabric kept
continuously wet
or by application of waterproof sheet materials.
G. Joint
sealant:
Install joint sealant at all
expansion joints and construction joints in
accordance with
manufacturer's installation instructions. Clean and prime
joints. Remove
dirt and loose coatings.
Apply sealant in continuous
beads, without open joints, voids, or air
pockets. Hand
tool and finish all joints.
Confine materials to joint areas
with masking tape or other precautions.
Remove excess compound promptly
as work progresses and clean adjoining
surfaces.
1. In rough surfaces or joints of uneven widths, install
joint sealant well
back into
joints.
3.04 FIELD QUALITY CONTROL: The Contractor
shall
A. Provide field quality control
testing and inspection during concrete
operations.
B. Provide adequate notice, cooperate
with, provide access to
the work, obtain samples, and
assist test agency and their representatives in
execution of their function.
C. Testing:
Provide slump test on first load
of concrete delivered each day and
whenever
requested due to changes in consistency or appearance of
concrete.
Provide air indicator tests and
air meter tests for all air-entrained
concrete.
Perform air indicator test with
a "Chase" AE 35 or equal air indicator, and
air meter test
in accordance with ASTM C231 or C173. Test first load of
concrete
delivered each day.
Furnish copies of field records
and tests reports as listed for strength
tests. Strength
testing:
D. Provide 1 set of 3 test specimens
for each 30 cu. yd. placed in any one day Secure samples in accordance with
ASTM C172 and mold specimens in
accordance with ASTM C31.
E. Test 1 specimen at 7 days and 2
specimens at 28 days in accordance with
ASTM C39.
F. The Contractor shall furnish copies
of field records and test reports as follows:
1 copy to Landscape Architect
2. 1 copy to Owner's representative
3. 1 copy to Contractor
4. 1 copy to Ready Mix Supplier
G. The Contractor shall record the
exact location of the concrete in the work represented by each set of cylinders
and show on test reports.
H. The Contractor shall provide an
insulated moist box for protection of the test cylinders until
shipped to the laboratory.
3.05 PROTECTION:
The Contractor shall protect concrete work
from damage due to construction and vehicular traffic until final acceptance.
Exclude construction and vehicular traffic from concrete pavements for at least
14 days.
3.06 CLEANING:
A. The Contractor shall remove from
site all excess materials, debris, and equipment. Repair damage resulting from
concrete operations.
B. The Contractor shall sweep concrete
sidewalks and pavement, wash free of stains, discoloration, dirt, and other
foreign material immediately prior to final acceptance.
END OF
SECTION