36C25622R0094 033000 Cast in Place Concrete.docx

REPLACE AHU #104 AND DUCTWORK BLDG. 7

DEPARTMENT OF VETERANS AFFAIRS HEALTH CARE SYSTEM-ALEXANDRIA, LA

PROJECT NO.: 502-19-107

SECTION 03 30 53

CASTINPLACE CONCRETE

GENERAL

SUMMARY

Section Includes:

Castinplace structural concrete.

Preparation of existing surfaces to receive concrete.

Preparation of existing surface to received concrete topping.

RELATED REQUIREMENTS

Materials Testing and Inspection During Construction: Section 01 45 29, TESTING LABORATORY SERVICES.

APPLICABLE PUBLICATIONS

Comply with references to extent specified in this Section.

American Concrete Institute (ACI):

11715 - Tolerances for Concrete Construction, Materials and Commentary.

301/310M10 - Structural Concrete.

305.114 - Hot Weather Concreting.

306.190(R2002) - Cold Weather Concreting.

318/318M14 - Building Code Requirements for Structural Concrete and SP6604ACI Detailing Manual.

34704 - Guide to Formwork for Concrete.

ASTM International (ASTM):

A615/A615M15ae1 - Deformed and Plain CarbonSteel Bars for Concrete Reinforcement.

A1064/A1064M15 - CarbonSteel Wire and Welded Wire Reinforcement, Plain and Deformed, for Concrete.

C33/C33M13 - Concrete Aggregates.

C39/C39M15a - Compressive Strength of Cylindrical Concrete Specimens.

C94/C94M15a - ReadyMixed Concrete.

C143/C143M15 - Slump of Hydraulic Cement Concrete.

C150/C150M15 - Portland Cement.

C192/C192M15 - Making and Curing Concrete Test Specimens in the Laboratory.

C21914a - Terminology Relating to Hydraulic Cement.

C260/C260M10a - AirEntraining Admixtures for Concrete.

C494/C494M15 - Chemical Admixtures for Concrete.

C61815 - Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete.

C881/C881M14 - EpoxyResinBase Bonding Systems for Concrete.

C989/C989M14 - Slag Cement for Use in Concrete and Mortars.

E115514 - Determining FF Floor Flatness and FL Floor Levelness Numbers.

International Concrete Repair Institute:

310.2R2013 - Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, Polymer Overlays, and Concrete Repair.

SUBMITTALS

Submittal Procedures: Section 01 33 23, SHOP DRAWINGS, PRODUCT DATA, AND SAMPLES.

Steel Reinforcing Shop Drawings:

Placing drawings that detail fabrication, bending, and placement. Include bar sizes, lengths, material, grade, bar schedules, stirrup spacing, bent bar diagrams, bar arrangement, splices and laps, mechanical connections, tie spacing, hoop spacing, and supports for concrete reinforcement.

Formwork Shop Drawings:

Prepared by or under the supervision of a qualified professional engineer detailing fabrication, assembly, and support of formwork.

Manufacturer's Literature and Data:

Concrete Mix Design.

Chemical admixtures and curing compounds.

Indicate manufacturer's recommendation for each application.

Material Test Reports: For the following, from a qualified testing agency, indicating compliance with requirements:

Aggregates.

Sustainable Construction Submittals:

Recycled Content: Identify postconsumer and preconsumer recycled content percentage by weight.

Certificates: Certify products comply with specifications.

Each ready-mix concrete batch delivered to site.

DELIVERY

Deliver each readymixed concrete batch with mix certification in duplicate according to ASTM C94/C94M.

QUALITY ASSURANCE

Installer Qualifications: A qualified installer who employs on Project personnel qualified as ACI-certified Flatwork Technician and Finisher and a supervisor who is an ACI-certified Concrete Flatwork Technician.

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.

Manufacturer certified according to NRMCA's "Certification of Ready Mixed Concrete Production Facilities."

Testing Agency Qualifications: An independent agency, acceptable to authorities having jurisdiction, qualified according to ASTM C 1077 and ASTM E 329 for testing indicated, as documented according to ASTM E 548.

Personnel conducting field tests shall be qualified as ACI Concrete Field-Testing Technician, Grade 1, according to ACI CP-01 or an equivalent certification program.

Personnel performing laboratory tests shall be ACI-certified Concrete Strength Testing Technician and Concrete Laboratory Testing Technician - Grade I. Testing Agency laboratory supervisor shall be an ACI-certified Concrete Laboratory Testing Technician - Grade II.

Source Limitations: Obtain each type or class of cementitious material of the same brand from the same manufacturer's plant, obtain aggregate from one source, and obtain admixtures through one source from a single manufacturer.

ACI Publications: Comply with the following unless modified by requirements in the Contract Documents:

ACI 301, "Specification for Structural Concrete," ACI 117, "Specifications for Tolerances for Concrete Construction and Materials."

Concrete Testing Service: Engage a qualified independent testing agency to perform material evaluation tests and to design concrete mixtures.

Preinstallation Conference: Conduct conference at Project Before submitting design mixtures, review concrete design mixture and examine procedures for ensuring quality of concrete materials. Require representatives of each entity directly concerned with cast-in-place concrete to attend, including the following:

Contractor's superintendent.

Independent testing agency responsible for concrete design mixtures.

Ready-mix concrete manufacturer.

Concrete subcontractor.

Review special inspection and testing and inspecting agency procedures for field quality control, concrete finishes and finishing, cold- and hot-weather concreting procedures, curing procedures, construction contraction and isolation joints, and joint-filler strips, forms and form removal limitations, shoring and reshoring procedures, vapor-retarder installation, anchor rod and anchorage device installation tolerances, steel reinforcement installation, floor and slab flatness and levelness measurement, concrete repair procedures, and concrete protection.

Construction Warranty: FAR clause 52.24621, "Warranty of Construction."

PRODUCTS

MATERIALS

Portland Cement: ASTM C150/C150M, Type I or II.

Pozzolans:

Fly Ash: ASTM C618, Class C or F including supplementary optional physical requirements.

Coarse Aggregate: ASTM C33/C33M.

Size 67 for other applications.

Fine Aggregate: ASTM C33/C33M.

Mixing Water: Fresh, clean, and potable.

Chemical Admixtures: ASTM C494/C494M.

Reinforcing Steel: ASTM A615/A615M or ASTM A996/A996M, deformed. See Structural Drawings for grade.

Forms: Wood, plywood, metal, or other materials, approved by Contracting Officer, of grade or type suitable to obtain type of finish specified.

Plywood: Exterior grade, free of defects and patches on contact surface.

Lumber: Sound, grademarked, S4S stress graded softwood.

Form coating: As recommended by Contractor.

Welded Wire Fabric: ASTM A1064/A1064M, plain; deformed; Grade 56; sized as indicated.

Expansion Joint Filler: ASTM D1751.

Sheet Materials for Curing Concrete: ASTM C171 or Liquid Membrane Forming Curing Compound: ASTM C 309, Type 1, Class A Grout, NonShrinking: Premixed ferrous or nonferrous. Grout to show no settlement or vertical drying shrinkage at 3 days. Compressive strength for grout, at least 2500 psi at 3 days and 5000 psi at 28 days.

ACCESSORIES

Bonding Agent: ASTM C 1059/C 1059M, Type II.

CONCRETE MIXES

Design concrete mixes according to ASTM C94/C94M, Option C.

Compressive strength at 28 days: minimum 4,000 psi.

Submit mix design and results of compression tests to the Contracting Officer for his evaluation. Identify all materials, including admixtures, makingup the concrete.

Maximum Slump for Vibrated Concrete: 100 mm (6 inches) tested according to ASTM C143.

Cement and Water Factor (See Table I):

TABLE I - CEMENT AND WATER FACTORS FOR CONCRETE

Min. 28 Day Comp. Str.

MPa (psi) Min. Cement kg/cu. m (lbs./cu. yd.)

Max. Water Cement Ratio

BATCHING AND MIXING

Store, batch, and mix materials according to ASTM C94/C94M.

JobMixed: Batch mix concrete in stationary mixers as specified in ASTM C94/C94M.

ReadyMixed Concrete: Comply with ASTM C94/C94M, except use of nonagitating equipment for transporting concrete to Site is not acceptable.

When aggregate producer's instructions deviate from specifications, submit proposed resolution for Contracting Officer's Representative consideration.

EXECUTION

FORMWORK

Installation: Conform to ACI 347. Construct forms to obtain concrete of the shapes, dimensions and profiles indicated, with tight joints.

Design and construct forms to prevent bowingout of forms between supports and to be removable without prying against or otherwise damaging fresh concrete.

When patching formed concrete, seal form edges against existing surface to prevent leakage; set forms so that patch is flush with adjacent surfaces.

Treating and Wetting: Treat or wet concrete contact surfaces:

Coat plywood and lumber forms with nonstaining form sealer.

Wet wood forms thoroughly when they are not treated with form release agent.

Prevent water from accumulating and remaining within forms.

Clean and coat removable metal forms with light form oil before reinforcement is placed.

In hot weather, cool metal forms by thoroughly wetting with water just before placing concrete.

Prevent water from accumulating and remaining within forms.

Inserts, Sleeves, and Similar Items: Install flashing reglets, masonry ties, anchors, inserts, wires, hangers, sleeves, boxes for floor hinges, and other castin items specified in other Sections. Place where indicated, square, flush and secured to formwork.

Construction Tolerances - General: Install and maintain concrete formwork to assure completion of work within specified tolerances.

Adjust or replace completed work exceeding specified tolerances before placing concrete.

REINFORCEMENT

Install concrete reinforcement according to ACI 318 and ACI SP66.

Support and securely tie reinforcing steel to prevent displacement during placing of concrete.

Drilling for Dowels in Existing Concrete: Use sharp bits, drill hole slightly oversize, fill with epoxy grout, inset the dowel, and remove excess epoxy.

PLACING CONCRETE

Remove water from excavations before concrete is placed. Remove hardened concrete, debris, and other foreign materials from interior of forms, and from inside of mixing and conveying equipment. Obtain approval from Contracting Officer's Representative before placing concrete.

Install screeds at required elevations for concrete slabs.

Roughen and clean free from laitance, foreign matter, and loose particles before placing new concrete on existing concrete.

Blowout areas with compressed air and immediately coat contact areas with adhesive in compliance with manufacturer's instructions.

Place structural concrete according to ACI 301 and ACI 318.

Convey concrete from mixer to final place of deposit by method that will prevent segregation or loss of ingredients. Do not deposit, in Work, concrete that has attained its initial set or has contained its water or cement more than 1 1/2 hours. Do not allow concrete to drop freely more than 1500 mm (5 feet) in unexposed work nor more than 900 mm (3 feet) in exposed work.

Place and consolidate concrete in horizontal layers not exceeding 12 inches in thickness. Consolidate concrete by spading, rodding, and mechanical vibrator. Do not secure vibrator to forms or reinforcement. Continuously vibrate during placement of concrete.

Hot Weather Concrete Placement: As recommended by ACI 305.1 to prevent adversely affecting properties and serviceability of hardened concrete.

Cold Weather Concrete Placement: As recommended by ACI 306.1, to prevent freezing of thin sections less than 300 mm (12 inches) and to permit concrete to gain strength properly.

Do not use calcium chloride without written approval from Contracting Officer's Representative.

PROTECTION AND CURING

Protect exposed surfaces of concrete from premature drying, wash by rain or running water, wind, mechanical damage, and excessive hot or cold temperatures.

Curing Methods: Cure concrete with curing compound using wet method with sheets.

Formed Concrete Curing: Wet the tops and exposed portions of formed concrete and keep moist until forms are removed.

If forms are removed before 14 days after concrete is cast, install sheet curing materials as specified above.

Concrete Flatwork Curing:

Install sheet materials according to the manufacturer's instructions.

When manufacturer's instructions deviate from specifications, submit proposed resolution for Contracting Officer's Representative consideration.

FORM REMOVAL

Maintain forms in place until concrete is selfsupporting, with construction operation loads.

Remove fins, laitance, and loose material from concrete surfaces when forms are removed. Repair honeycombs, rock pockets, sand runs, spalls, or otherwise damaged surfaces by patching with the same mix as concrete minus the coarse aggregates.

Finish to match adjacent surfaces.

FINISHES

Vertical and Overhead Surface Finishes:

Surfaces Concealed in Completed Construction: Ascast; no additional finishing required.

Surfaces Exposed to View in Finished Areas: Grout finish, unless otherwise shown, for uniform color and smooth finish treated.

Remove laitance, fins, and burrs.

Scrub concrete with wire brushes. Clean stained concrete surfaces with hone or stone.

Apply grout composed of 1 part Portland cement and 1-part clean, fine sand (smaller than 600 microm (No. 30) sieve). Work grout into surface of concrete with cork floats or fiber brushes until pits and honeycomb are filled.

After grout has hardened, but is still plastic, remove surplus grout with sponge rubber float and by rubbing with clean burlap.

In hot, dry weather fog spray surfaces with water to keep grout wet during setting period. Complete finished areas in same day. Confine limits of finished areas to natural breaks in wall surface. Do not leave grout on concrete surface overnight.

Slab Finishes:

Allow bleed water to evaporate before surface is finished. Do not sprinkle dry cement on surface to absorb water.

Broom Finish: Finish exterior slabs, ramps, and stair treads with bristle brush moistened with clear water after surfaces have been floated.

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