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SECTION 033000 - CAST-IN-PLACE CONCRETE FOR EXTERIOR WALKWAYS & CURBING


PART 1 - GENERAL

1.1 SUMMARY

A. Section includes cast-in-place concrete, including formwork, reinforcement, concrete materials,
mixture design, placement procedures, and finishes.

1.2 ACTION SUBMITTALS
A. Product Data: For each type of product indicated.
B. LEED Submittals (if applicable to project):

1. Product Data for Credit MR 4: For products having recycled content, documentation
indicating percentages by weight of postconsumer and preconsumer recycled content.
Include statement indicating cost for each product having recycled content.

2. Product Data for Credit IEQ 4.3: For curing and sealing compounds, documentation
including printed statement of VOC content.

3. Design Mixtures for Credit ID 1.1: For each concrete mixture containing fly ash as a
replacement for portland cement or other portland cement replacements, and for
equivalent concrete mixtures that do not contain portland cement replacements.

C. Design Mixtures: For each concrete mixture.

D. Steel Reinforcement Shop Drawings: Placing drawings that detail fabrication, bending, and placement.

1.3 INFORMATIONAL SUBMITTALS
A. Welding certificates.
B. Material certificates.
C. Material test reports.

1.4 QUALITY ASSURANCE
A. Manufacturer Qualifications: A firm experienced in manufacturing ready-mixed concrete
products and that complies with ASTM C 94/C 94M requirements for production facilities and
equipment.
1. Manufacturer certified according to NRMCA's "Certification of Ready Mixed Concrete
Production Facilities."

B. Installer Qualifications: An experienced installer who has completed concrete work similar in
material, design, and extent to that indicated for this project and whose work has resulted in
construction with a record of successful in-service performance.

C. Welding Qualifications: Qualify procedures and personnel according to AWS D1.4/D 1.4M,
"Structural Welding Code - Reinforcing Steel."

D. ACI Publications: Comply with the following unless modified by requirements in the Contract
Documents:
1. ACI 301, "Specifications for Structural Concrete," Sections 1 through 5.
2. ACI 117, "Specifications for Tolerances for Concrete Construction and Materials."

E. Preinstallation Conference: Conduct conference at Project site.

PART 2 - PRODUCTS
2.1 GENERAL

A. ACI Publications: Comply with the following unless modified by requirements in the contract
documents:
1. ACI 301
2. ACI 303.1

2.2 STEEL REINFORCEMENT

A. Recycled Content of Steel Products: Postconsumer recycled content plus one-half of
preconsumer recycled content not less than 25 percent.

B. Reinforcing Bars: ASTM A 615, Grade 60 (Grade 420), deformed.
1. Epoxy-Coated Reinforcing Bars: ASTM A 775, epoxy coated, with less than 2 percent
damaged coating in each 12-inch (300-mm) bar length.

C. Plain-Steel Welded Wire Reinforcement: ASTM A 185, plain, fabricated from as-drawn steel
wire into flat sheets.

D. Deformed-Steel Welded Wire Reinforcement: ASTM A 497, flat sheet.

E. Bar Supports: Bolsters, chairs, spacers, and other devices for spacing, supporting, and fastening
reinforcing bars and welded wire reinforcement in place. Manufacture bar supports from steel
wire, plastic, or precast concrete according to CRSI's "Manual of Standard Practice.

2.3 CONCRETE MATERIALS
A. Cementitious Material: Use the following cementitious materials, of the same type, brand, and
source, throughout Project:

1. Portland Cement: ASTM C 150, Type I/II. Supplement with the following:
a. Fly Ash: ASTM C 618, Class F or C.
b. Ground Granulated Blast-Furnace Slag: ASTM C 989, Grade 100 or 120.
B. Normal-Weight Aggregates: ASTM C 33, graded.
1. Maximum Coarse-Aggregate Size: per ACI 318.
2. Fine Aggregate: Free of materials with deleterious reactivity to alkali in cement.
C. Water: ASTM C 94 and potable.
2.4 ADMIXTURES

A. Air-Entraining Admixture: ASTM C 260.

B. Chemical Admixtures: Provide admixtures certified by manufacturer to be compatible with
other admixtures and that will not contribute water-soluble chloride ions exceeding those
permitted in hardened concrete. Do not use calcium chloride or admixtures containing calcium
chloride.
1. Water-Reducing Admixture: ASTM C 494, Type A.
2. Retarding Admixture: ASTM C 494, Type B.
3. Water-Reducing and Retarding Admixture: ASTM C 494, Type D.
4. High-Range, Water-Reducing Admixture: ASTM C 494, Type F.
5. High-Range, Water-Reducing and Retarding Admixture: ASTM C 494, Type G.
6. Plasticizing and Retarding Admixture: ASTM C 1017, Type II.

2.5 FIBER REINFORCEMENT
A. Synthetic Micro-Fiber: Monofilament or fibrillated polypropylene micro-fibers engineered and
designed for use in concrete, complying with ASTM C 1116, Type III, 1/2 to 1-1/2 inches (13 to
38 mm) long.

2.6 CURING MATERIALS
A. Clear, Solvent-Borne, Membrane-Forming Curing and Sealing Compound: ASTM C 1315,
Type 1, Class A.
1. VOC Content: Curing and sealing compounds shall have a VOC content of 200 g/L or
less when calculated according to 40 CFR 59, Subpart D (EPA Method 24).
B. Clear, Waterborne, Membrane-Forming Curing and Sealing Compound: ASTM C 1315,
Type 1, Class A.
1. VOC Content: Curing and sealing compounds shall have a VOC content of 200 g/L or
less when calculated according to 40 CFR 59, Subpart D (EPA Method 24).

2.7 RELATED MATERIALS
A. Expansion- and Isolation-Joint-Filler Strips: ASTM D 1751, asphalt-saturated cellulosic fiber
or ASTM D 1752, cork or self-expanding cork.
B. Bonding Agent: ASTM C 1059, Type II, non-redispersible, acrylic emulsion or styrene
butadiene.
C. Epoxy-Bonding Adhesive: ASTM C 881, two-component epoxy resin, of type, class, and grade
to suit requirements.
D. Evaporation Retarder: Waterborne, monomolecular film forming, manufactured for application
to fresh concrete.


2.8 CONCRETE MIXTURES
A. Prepare design mixtures for each type and strength of concrete, proportioned on the basis of
laboratory trial mixture or field test data, or both, according to ACI 301.
B. Cementitious Materials: Use fly ash, pozzolan, ground granulated blast-furnace slag, and/or
silica fume as needed to reduce the total amount of portland cement, which would otherwise be
used, by not less than 25 percent nor more than 50 percent.
C. Admixtures: Use admixtures according to manufacturer's written instructions.
1. Use water-reducing, high-range water-reducing or plasticizing admixture in concrete, as
required, for placement and workability.
2. Use water-reducing and retarding admixture when required by high temperatures, low
humidity, or other adverse placement conditions.
D. Proportion normal-weight concrete mixture as follows:


EXTERIOR CONCRETE WALKWAYS & CURBING

1. Minimum Compressive Strength: 4000 psi at 28 days.
2. Maximum Water-Cementitious Materials Ratio: 0.50.
3. Slump Limit: 8 inches for concrete with a verified slump of less than 5 inches before
adding water-reducing or plasticizing admixtures.
4. Air Content: 6 percent, plus or minus 1.5 percent at point of delivery for 1-inch nominal
maximum aggregate size.
5. Synthetic Micro-Fiber: Uniformly disperse in concrete mixture at manufacturer's
recommended rate, but not less than 1.5 lb/cu. yd.


2.9 FABRICATING REINFORCEMENT
A. Fabricate steel reinforcement according to CRSI's "Manual of Standard Practice."


2.10 CONCRETE MIXING

A. Ready-Mixed Concrete: Measure, batch, mix, and deliver concrete according to
ASTM C 94 and ASTM C 1116, and furnish batch ticket information.
1. When air temperature is between 85 and 90 deg F (30 and 32 deg C), reduce mixing and
delivery time from 1-1/2 hours to 75 minutes; when air temperature is above 90 deg F (32
deg C), reduce mixing and delivery time to 60 minutes.
B. Project-Site Mixed Concrete: Measure, batch, and mix concrete materials and concrete
according to ASTM C 94. Mix concrete materials in appropriate drum-type machine mixer.

PART 3 - EXECUTION

3.1 FORMWORK
A. Design, erect, shore, brace, and maintain formwork, according to ACI 301, to support vertical,
lateral, static, and dynamic loads, and construction loads that might be applied, until structure
can support such loads.
B. Construct formwork so concrete members and structures are of size, shape, alignment,
elevation, and position indicated, within tolerance limits of ACI 117.

3.2 EMBEDDED ITEMS
A. Place and secure anchorage devices and other embedded items required for adjoining work that
is attached to or supported by cast-in-place concrete. Use setting drawings, templates,
diagrams, instructions, and directions furnished with items to be embedded.

3.3 STEEL REINFORCEMENT

A. General: Comply with CRSI's "Manual of Standard Practice" for placing reinforcement.

3.4 JOINTS
A. General: Construct joints true to line with faces perpendicular to surface plane of concrete.
B. Construction Joints: Install so strength and appearance of concrete are not impaired, at
locations indicated or as approved by Owner. Install slip dowels to prevent differential vertical
displacement, yet allow for horizontal movement of the joint.
C. Contraction Joints in Slabs-on-Grade: Form weakened-plane contraction joints, sectioning
concrete into areas as indicated. Construct contraction joints for a depth equal to at least onefourth
of concrete thickness as follows:

1. Grooved Joints: Form contraction joints by grooving and finishing each edge of joint to a
radius of 1/4 inch (3.2 mm). Repeat grooving of contraction joints after applying surface
finishes. Eliminate groover tool marks on concrete surfaces.
D. Isolation Joints in Slabs-on-Grade: After removing formwork, install joint-filler strips at slab
junctions with vertical surfaces, such as column pedestals, foundation walls, grade beams, and
other locations, as indicated.


3.5 CONCRETE PLACEMENT
A. Before placing concrete, verify that installation of formwork, reinforcement, and embedded
items is complete and that required inspections have been performed.
B. Deposit concrete continuously in one layer or in horizontal layers of such thickness that no new
concrete will be placed on concrete that has hardened enough to cause seams or planes of
weakness. If a section cannot be placed continuously, provide construction joints as indicated.
Deposit concrete to avoid segregation.
1. Consolidate placed concrete with mechanical vibrating equipment according to ACI 301.
2. Screed and initial-float concrete floors and slabs using bull floats or darbies to form a
uniform and open-textured surface plane, free of humps or hollows, before excess
moisture or bleedwater appears on the surface. Do not further disturb slab surfaces
before starting finishing operations.
C. Cold-Weather Placement: Comply with ACI 306R.
D. Hot-Weather Placement: Comply with ACI 305R.

3.6 FINISHING
A. General: Comply with ACI 302.1R recommendations for screeding, restraightening, and
finishing operations for concrete surfaces. Do not wet concrete surfaces.
B. Broom Finish: Apply a broom finish to concrete by brooming with fiber-bristle broom
perpendicular to main traffic route, to platforms, steps, ramps, walkways and elsewhere as
indicated.

3.7 CONCRETE PROTECTING AND CURING
A. General: Protect freshly placed concrete from premature drying and excessive cold or hot
temperatures. Comply with ACI 306.1 for cold-weather protection and ACI 301 for hotweather
protection during curing.
B. Evaporation Retarder: Apply evaporation retarder to unformed concrete surfaces if hot, dry, or
windy conditions cause moisture loss approaching 0.2 lb/sq. ft. x h (1 kg/sq. m x h) before and
during finishing operations. Apply according to manufacturer's written instructions after
placing, screeding, and bull floating or darbying concrete, but before float finishing.
C. Begin curing after finishing concrete but not before bleed water has disappeared from concrete
surface. Cure concrete according to ACI 308.1 by the following method:
1. Curing and Sealing Compound: Apply uniformly to floors and slabs indicated in a
continuous operation by power spray or roller according to manufacturer's written
instructions while concrete surface is still moist. Recoat areas subjected to heavy rainfall
within three hours after initial application. Repeat process and apply a second coat at a
right angle to the first coat. Maintain continuity of coating and repair damage during
curing period.

3.8 CONCRETE SURFACE REPAIRS
A. Defective Concrete: Repair and patch defective areas when approved by Owner. Remove and
replace concrete that cannot be repaired and patched to Owner's approval.

3.9 FIELD QUALITY CONTROL
A. Testing and Inspecting: Owner will engage a qualified testing and inspecting agency to sample
materials, perform tests, and submit test reports during concrete placement. Tests shall be
performed according to ACI 301.

3.10 CONCRETE CURB
A. The following specifications and standards of the issues listed are to be utilized:
1. Commonwealth of Pennsylvania Department of Transportation Specifications,
Publication 408 and Supplements, latest edition, hereinafter referred to as Pub. 408.
2. American Society of Testing Materials (ASTM).
B. All concrete curb work shall be constructed in conformance with the latest edition Pub. 408,
Section 630, as noted and amended herein:
1. Concrete mix design as per Section 2.8(D) of this specification.
2. Curb shall be a monolithic pour with form or saw contraction joints 3/16-inch wide and 2
inches deep.
3. Contraction joints shall be spaced at 4’ minimum and 20’ maximum.
4. Concrete curb may be placed with an acceptable, self-propelled machine as approved by
the University and in accordance with Pub. 408, Section 630.3(d). Comply with all curb
profiles and dimensions.
5. Use acceptable metal forms as per Section 501.3(d). Wood forms may be used on sharp
curves as detailed in Section 501.3(d).
6. Match curb profiles where new work is an extension or revision of existing.
7. Construct curb to details shown on plans.

3.11 EXTERIOR CONCRETE WALKWAYS:
A. The following specifications and standards of the issues listed are to be utilized:
1. Commonwealth of Pennsylvania Department of Transportation Specifications,
Publication 408 and Supplements, latest edition, hereinafter referred to as Pub. 408.
2. American Society for Testing Materials (ASTM).
3. American Concrete Institute (ACI).
4. American Association of State Highway and Transportation Officials (AASHTO).
B. Before placing aggregate bed for concrete walkway, check the subgrade and do all necessary
grading, rolling, and compacting required to attain a true, even, firm surface. Fill and
consolidate any traces of dented or depressed areas. Remove all spongy material, replace with
suitable earthfill, and compact solidly with roller or mechanical compactors; moisten if
required.
C. Provide a 2A crushed aggregate subbase course fully choked and rolled to the compacted
thickness indicated on the drawings. Aggregate for subbase course shall be Type C, or better,
as specified in Pub. 408, Section 703.2.
D. Joints:
1. Use ¼” thick premolded expansion joint material the specified depth of the concrete slabs
along all foundations and walls where slabs abut other fixed structures; longitudinally
where sidewalk slab is to be constructed in contact with curb, and adjacent to existing
structures as directed.
2. Construction joints shall be located at the discretion of the Contractor accommodating the
joint pattern on the drawings. See typical details.
3. Where existing and/or new light standards, poles, fire hydrants, access frames and covers
to underground utilities, manhole frames and covers, and similar structures are within the
limits of the sidewalk areas, the concrete around such structure shall be scored, by edging
and/or grooving, in a block 8” wider than the maximum dimensions of the structure at the
sidewalk elevation. Prior to placing the concrete around such structures, premolded
expansion joint material shall be placed around the structure to the full depth of the slab.
4. Unless otherwise directed by the University, a metal edger having a ¼” radius shall be
used for edging all joints. Transverse and longitudinal scoring shall be done in
accordance with the drawings and/or directed. Scoring and control joints shall extend to
a depth of at least ¼ of the thickness of the slab.
E. Forms:
1. Forms may be metal or wood, securely staked and braced, and constructed to true lines
and shapes indicated and extending the full depth of the concrete.
2. Forms shall be oiled if metal or wetted or oiled if wood. Form oil shall be an approved
form coating. Care shall be taken to prevent reinforcement from becoming coated with
form oil.
3. Forms once used shall be thoroughly cleaned before being reused.
4. Side forms shall not be removed within 12 hours after the concrete has been placed.
After the removal of forms, minor honeycomb at formed areas shall be filled with mortar
composed of 1 part cement and 2 parts fine aggregate. Major honeycomb areas will be
considered as defective work, and shall be removed and replaced at no additional cost to
the University.
F. Placing Concrete Walkways:
1. All concrete work shall conform to referenced and applicable standards and the latest
American Concrete Institute Manual of Concrete Practice.
2. Sidewalk slabs shall be one-course construction of thickness indicated on drawings but in
no case less than a full five (5) inches, unless otherwise specified on the drawings.
3. Do not increase the quantity of water in the concrete beyond the recommended design
limit.
G. Weather Requirements:
1. Placement of concrete under extreme weather conditions shall take place only after
approval from the University.
H. Protection and Cleaning:
1. All finished concrete work shall be protected from damage due to subsequent
construction operations. All concrete work from which traffic cannot be restricted shall
be protected by use of approved covering, temporary ramps or walkways.
2. New construction adjacent to concrete work areas shall be protected from splashing and
damage, by protective coverings of waterproof paper, plastic, and\or wood members as
required.
I. Finishing of Concrete Walkways:
1. All exterior concrete walkways shall be given a coarse stiff bristle broom finish
perpendicular to the line of traffic to produce a non-slip surface. See plan for other
finishes.
2. The edges and perimeter, and control joint scoring of all slabs, shall be edged, with a
metal edger having a ¼-inch radius, to produce a dense compact border outlining each
slab.
END OF SECTION 033000

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