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SECTION 03300 - CAST-IN-PLACE CONCRETE

PART 1 - GENERAL

1.1 APPLICABLE STANDARDS: Conform to the latest following Standards, unless noted otherwise:

ASTM C31: Making and Curing Concrete Test Specimens in the Field. ASTM C33: Concrete Aggregates. ASTM C39: Compressive Strength of Cylindrical Concrete Specimens. ASTM C42: Obtaining and Testing Drilled Cores and Sawed Beams of Concrete. ASTM C94: Ready-Mixed Concrete. ASTM C138: Unit Weight, Yield, and Air Content (Gravimetric) of Concrete. ASTM C143: Slump of Portland Cement Concrete. ASTM C150: Portland Cement. ASTM C172: Sampling Fresh Concrete. ASTM C173: Air Content of Freshly Mixed Concrete by the Volumetric Method. ASTM C183: Sampling Hydraulic Cement. ASTM C192: Making and Curing Concrete Test Specimens in the Laboratory. ASTM C231: Air Content of Freshly Mixed Concrete by the Pressure Method. ASTM C260: Air-Entraining Admixtures for Concrete. ASTM C494: Chemical Admixtures for Concrete. ASTM C595: Blended Hydraulic Cements ASTM C618: Fly Ash and Raw or Calcined Natural Pozzolan for use as a Mineral Admixture in Portland Cement Concrete. ASTM C1116: Standard Specification for Fiber-Reinforced Concrete ASTM D75: Sampling Aggregates.

ACI 211.1: Recommended Practice for Selecting Proportions for Normal and Heavyweight Concrete. ACI 214: Recommended Practice for Evaluation of Compression Test Results of Field Concrete. ACI 301: Specifications for Structural Concrete For Buildings. ACI 304: High Density Concrete: Measuring, Mixing, Transporting, and Placing.

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Contract No. 1604-0795

Rev 0 (11-APR-2016) 03300-1 Paving Projects.18-GA-10201293/10203940 4/18/18


ACI 305: Hot Weather Concreting.

ACI 306: Recommended Practice for Cold Weather Concreting. ACI 308: Recommended Practice for Curing Concrete. ACI 318-99: Building Code Requirements for Reinforced Concrete. ACI 347: Recommended Practice for Concrete Formwork. Ga. DOT: State of Georgia, Department of Transportation

IBC 2006: International Building Code

1.2 SUMMARY

A. Section Includes: Formwork, reinforcing, inserts, sleeves, accessories, and miscellaneous

embedded items, and cast-in-place concrete.

B. Mandatory Provisions: In publications referred to herein, advisory provisions are considered to

be mandatory: for example, substitute the word "shall" for "should" whenever it appears

1.3 SUBMITTALS

A. Concrete Supplier(s) and Certifications: Name and address of each proposed concrete supplier

and certifications by National Concrete Ready-Mix Concrete Association and State Department

of Transportation. Submit 28 days minimum prior to use.

B. Concrete Mix Design: Submit concrete mix design for each type of concrete specified 21 days

minimum prior to use of each mix. Include following for each mix:

1. Separate sieve analyses of percentages passing and retained for fine and coarse aggregates,

including fineness modulus. Include following sieve sizes: 2 inch, 1-1/2 inch, 1 inch, 3/4

inch, 1/2 inch, 3/8 inch, No. 4, No. 8, No. 16, No. 30, No. 50, No. 100, and No. 200. For

slabs, pavements, watertight concrete, and other concrete noted on Drawing also provide

sieve analysis of percentage retained for combined coarse and fine aggregates.

2. Type of fine aggregate, whether natural or manufactured.

3. Ensure aggregate supplier reports if aggregate is possibly reactive, based on tests or past

service.

4. Ensure aggregate supplier reports if aggregate can possibly cause pop-outs, "D" cracking,

or other disruptions due to moisture gain or other mechanisms, based on tests or past service.

C. Curing:

1. Proposed methods and materials for curing.

2. Submit 14 days minimum prior to use.

D. Reinforcing Bar Shop Drawings:

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1. Complete information for installing reinforcing, including placement plans, bar bending

diagrams, splice lengths and locations, bar spacing, concrete cover, support devices, and

accessories.

2. Conform to ACI 315 and ACI SP-66, except conform to ACI 318 when utilizing ACI SP-66

for splices and other data.

E. Product Data: Brand name, chemical composition, installation directions, and certificate of compliance with required standards for the following products 14 days minimum prior to use:

1. Air-entraining admixture.

2. Low-range water-reducing admixture. 3. Mid-range water-reducing admixture.

4. High-range water-reducing admixture.

5. Retarding admixture.

6. Accelerating admixture.

7. Fly ash.

8. Forms and liners.

9. Form sealer.

10. Form release agent.

11. Gaskets, sealants, and other formwork accessories. 12. Waterstops.

13. Pre-molded joint filler. 14. Sheet materials for curing concrete.

15. Liquid membrane curing and sealing compound.

F. Delivery Tickets:

1. Copies of delivery tickets for each load of concrete delivered to site.

2. Indicate on each ticket information required by ASTM C 94.

3. For slabs and watertight concrete also indicate on each ticket additional information noted in ASTM C 94.

4. Mix identification number on ticket to match number on submitted and approved mix

design noted above.

5. Submit copies to Owner's Representative same day as concrete delivery, and submit copies

to Engineer within 3 days maximum after delivery.

G. Method of Adding High-range Water-reducing Admixture:

1. Proposed method and location of adding high-range water-reducing admixture to concrete

mix, if this admixture is proposed to be used.


H. Coarse Aggregate Base:

1. Sieve analysis of coarse aggregate base.


I. Joint Types and Locations:

1. Proposed joint types and locations for joints not shown on Drawings.

2. Submit 7 days minimum prior to placing concrete in area concerned.

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1.4 QUALITY CONTROL AND QUALITY ASSURANCE

A. Testing Requirements:

1. All testing Agency Selected and Paid by Contractor:

a. Proportion concrete materials on basis by laboratory trial batches in accordance with

ACI 318. b. Ready-mix concrete supplier can proportion materials by field experience, per ACI

318.

c. Proportioning by water-cement ratio, per ACI 318, is not acceptable. d. Submit to Engineer for review copies of data and test results to substantiate mix

designs. e. Test reinforcing steel, aggregate, and other products to substantiate specified

compliance. f. Test concrete materials for compressive strength, air content, temperature, and slump

in accordance with ASTM C 31 and C 39.

1) Perform 4 tests on each 50 cubic yards for each class concrete placed per day but

not less than once for each day of concrete placement.

2) When specified schedule of testing provides less than 5 tests for a given class of

concrete, test at least 5 randomly selected batches; if fewer than 5 batches are

used, test each batch.

3) Perform slump and temperature tests for first 3 truck loads of concrete and every

other truck thereafter.

4) Report to Engineer, Contractor, and concrete supplier a record of location of each

placement represented and test results.

g. Include test cylinders for each compressive strength test to be tested for not less than

as follows for design age strength:

1) 28 Day Strength: 1 at 5 days, 1 at 7 days, 2 at 28 days, 1 reserve.

h. When mid-range or high-range water-reducing admixture is added on-site to produce

slumps in excess of that for concrete without noted admixture, take additional slump

tests as follows:

1) Take 1 from first batch before admixture is added.

2) Take 1 from first batch after the admixture is added and mixer has revolved number of turns recommended by admixture manufacturer.

3) After first batch, take 1 from every other batch before admixture is added.

i. When pumping concrete, take samples for tests at point of delivery from pumping

line, except first slump test noted above for concrete with mid-range or high-range

water-reducer.

j. Make and test additional test cylinders for determining starting times for specified

work. Field-cure test cylinders in environment as close as possible to that of

structure(s) concerned. Make, cure, and test cylinders in accordance with ASTM C 31

and C 39. Ensure Contractor determines number of additional field-cured test

cylinders required and submits proposed number of cylinders to Engineer for their

concurrence. Costs of tests by Contractor.

1) Formwork removal.

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2) Reshores removal.

3) Putting structures into service.

k. Failure to detect defective material or Work will neither prevent rejection when

defects are discovered later, nor will it obligate Owner to make final acceptance.

B. Allowable Tolerances:

1. Formwork: Conform to most stringent requirements of ACI 117, ACI 301, and ACI 347R,

except as specified herein.

2. Items Other Than Formwork: Conform to ACI 117, except as specified. 3. Concrete on Grade Base Fine Grade: +0 inch, -3/4 inch, with transition no greater than 3/4

inch vertically to 8 inches horizontally.

4. Concrete on Grade Thickness: + as required to conform to finished surface flatness and

levelness tolerances specified, -1/4 inch.

5. Finished Surface Flatness and Levelness:

a. The surface will be tested by using a 10-foot straight edge. The variation of the surface from the testing edge of the straight edge between any two contacts with the

surface shall not be more then ¼-inch. Humps and depressions exceeding the

specified tolerance shall be corrected or the defective work shall be removed and

replaced with new material.

6. Runway Dowels:

a. 0.075 inch maximum in dowel straightness.

b. Plus or minus 1/8 inch in dowel alignment in vertical and horizontal planes.

C. Workmanship:

1. Remove and replace or repair concrete-related Work which does not conform to specified

requirements including strength, tolerances, and finishes as directed by Owner at

Contractor's expense without extension of Contract time.

2. Bear cost of corrections or delays to other Work affected by or resulting from corrections to concrete Work.

3. If results of compressive strength tests reveal deficiencies in concrete, meet requirements of ACI 318 and ACI 301.

D. Concrete Plant Certification: Certify primary and secondary plants proposed for furnishing

ready-mix concrete as being approved at highest level by NCRMA and by Department of

Transportation in state where project is located. Submit certification documentation.

E. Ready-Mix Concrete Trucks:

1. Ready-mix concrete trucks to conform to ASTM C 94 and NCRMA.

2. For slabs, pavements, and watertight concrete trucks to conform to NCRMA and

Department of Transportation standards in state where project is located.

3. Do not bring on site for those concreting operations any truck whose numbers are not

recorded as acceptable.

F. Notification for Engineer Observation of Installed Formwork and Reinforcement: Notify

Engineer 3 working days minimum prior to placing concrete to allow time for observation of

installed formwork and reinforcing.

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G. Payment:

1. All testing shall be paid by the Contractor.

H. Quality Assurance:

Contractor shall notify the Owner’s Representative a minimum of 48 hours prior to placing the concrete so that the Representative may inspect the rebar and base prior to placing final form.

Representative shall put in writing that the work has been inspected and whether it has been approved or not within 24 hours of the inspection. If not approved, Representative shall notify

the contractor in writing after the inspection so that deficiencies can be corrected. After

deficiencies are corrected, the Contractor shall notify the rep so that the Representative can re-inspect and approve the work. Representative shall also put in writing that the work has been

re-inspected and approved within 24 hours of the re-inspection.

1.5 PRODUCT DELIVERY, STORAGE, AND HANDLING

A. Deliver packaged items in manufacturer's container with seals intact.

B. Mark reinforcing, accessories, and embedded items for proper identification and placement

location.

C. Store materials, except aggregate, off ground and protect from moisture and contamination.

D. Stockpile aggregate in manner to prevent contamination with other materials or with other

sizes of aggregates. Conduct tests for determining conformance to requirements at point of

batching. Do not use bottom 6 inches of aggregate piles in contact with ground. Allow sand to

drain until it has reached a uniform moisture content before it is used.

E. Store admixtures in manner to prevent contamination. Protect admixtures from extreme

temperatures which would adversely affect their characteristics.

1.6 ENVIRONMENTAL CONDITIONS

A. Concreting in Hot, Dry and/or Windy Weather:

1. Conform to ACI 305R when any combination of high air or concrete temperature, low

relative humidity, and wind velocity tend to impair quality of concrete.

2. Employ special precautions when evaporation rate as obtained from ACI 305R is expected to reach 0.2 pound per square foot per hour or more.

3. For slabs, reject concrete if its temperature before placement is 85°F or above. For other

concrete, reject concrete if its temperature before placement is 90°F or above.

4. During hot weather mixing and delivery (discharge) time to be shorter than specified in

ASTM C 94 if retarding admixture is not permitted by Engineer.

5. When air temperature is between 85°F and 90°F, reduce allowable mixing and delivery

time from 90 minutes to 75 minutes.

6. When air temperature is over 90°F, reduce allowable mixing and delivery time to 60

minutes.

7. Do not place concrete when forms, subgrade, base, or reinforcing bars are more than 120°F

or more than 10°F hotter than ambient air temperature.

8. Cool with water or water-soaked burlap as necessary, but allow no standing water on surface on which concrete is placed.

B. Concreting in Cold Weather:

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1. Conform to ACI 306R and 306.1 when temperature and other environmental conditions are

as noted therein and following additional requirements:

a. Immediately before placing concrete, metal embedments and other metal items in

contact with concrete to be at temperature above 32°F if 1 or more of following conditions are met:

1) Metal item weighs more than 15 pounds per linear foot.

2) Metal item is compact and weighs more than 50 pounds total.

3) Items noted on Drawings.

b. Subgrade to be thawed to depth of 12 inches immediately before placing concrete.

c. Per ACI 306.1 measure concrete temperature during protection period in each

placement at regular time intervals, but not less than 3 times per 24-hour period.

d. Before removal of weight supporting forms or reshoring, concrete compressive

strength to be at least 80% of design compressive strength.

2. Do not place slabs on subgrade, base, or forms that are more than 20°F cooler than

concrete. Warm subgrade, base, or deck to decrease temperature differential to 20°F or

less.

C. Precipitation Protection: Protect surfaces of exposed concrete from precipitation until adequate

strength is gained to prevent damage.

PART 2 - PRODUCTS

2.1 MATERIALS

A. Cement:

1. ASTM C 150, Type II.

2. Use only 1 brand throughout project.

B. Aggregates:

1. ASTM C 33, with following requirements:

a. Consider concrete not covered by building materials or soil to be subject to abrasion

and in severe weathering region.

b. Allow no coal or lignite in concrete that will not be covered by building materials or

soil.

c. Fine aggregate shall not have more than 35 % passing any sieve and retained on

the next consecutive sieve as shown in 5.1 of ASTM C33

2. Do not use manufactured aggregates unless blended with natural sand.

3. Coarse Aggregate: Use 67 or 57 Stone. Minimum Specific Gravity 2.6.

C. Water: Potable.

D. Admixtures:

1. General:

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a. No admixture to contain more than 0.1% chloride ions. Submit certificate of

compliance to this requirement.

b. Submit information needed for manufacturer to determine if there is problem with

compatibility.

2. Types:

a. Air-entraining: ASTM C 260.

b. Water-reducing: ASTM C 494, Type A.

c. High-range Water-reducing: ASTM C 494, Type F or G.

1) Type F Acceptable Products and Manufacturers:

a) "Eucon 37" by Euclid Chemical Corp.

b) "Daracem 100" by W. R. Grace & Co.

c) "Rheobuild 1000" by Master Builders.

2) Type G Acceptable Products and Manufacturers:

a) "Eucon 537" by Euclid Chemical Corp.

b) "Daracem 100" by W. R. Grace & Co. c) "Rheobuild 716" by Master Builders.

d. Retarding: ASTM C 494, Type B or D.

e. Accelerating:

1) ASTM C 494, Type C or E. Non-chloride and non-thiocyanate type.

2) Acceptable Products and Manufacturers:

a) "Accelguard 80" by Euclid Chemical Corp.

b) "Darex Set Accelerator" by W.R. Grace & Co.

E. Fly Ash: ASTM C 618, class F, except loss on ignition not to exceed 3%.

F. Reinforcing Bars:

1. ASTM A 615, deformed, Grade 60

G. Reinforcing Support Devices:

1. CRSI's "Manual of Standard Practice".

2. When legs of support devices rest directly on formwork, zinc coat devices after fabrication

or provide stainless steel accessories or plastic button tips at wire ends to prevent staining

of concrete by rust.

3. Over fine or coarse aggregate base, waterproof membranes, and vapor barriers, use precast

concrete chairs with properly embedded tie wires or other type of supports acceptable to

Engineer to prevent penetration of substrate.

4. Do not use wood, brick, and other such devices that can expand due to moisture gain.

5. Precast concrete chairs to have minimum compressive strength of 4000

psi.Formwork:Plywood for Concrete Surfaces Not to be Exposed After Construction is

Complete:

a. APA B-B Plyform exterior grade or better, Class I, with straight, sealed edges and 5/8

inch minimum thickness.

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b. HDO Plyform is acceptable.

2. Plywood for Concrete Surfaces to be Exposed After Construction is Complete: APA HDO Plyform, exterior grade or better, Class I, with straight, sealed edges and 5/8 inch

minimum thickness. 3. Lumber: Dressed, tongue and grooved, free from loose knots.

4. Metal: Smooth, clean, corrosion-free, without dents or holes, with closely-matching edges. 5. Fiberglass: Smooth, clean, without dents or holes, with closely-matching edges.

6. Laminated Round Fiber Tubes: Spirally laminated paper fiber, wax impregnated on

exterior surfaces, interior ply allowing uniform moisture penetration.

I. Form Release Agents:

1. Type acceptable to cement manufacturer, will not cause surface imperfections, non-staining, and compatible with field applied paints, toppings, linings, curing compounds,

and other coatings. 2. Use same brand form release agent for all forms.

J. Form Accessories:

1. Form ties, anchors and hangers of sufficient strength to completely resist displacement of

forms due to construction loads and depositing of concrete.

2. Provide ties and spreader form ties designed so no metal will be within 1 inch of surface

when forms are removed.

3. Where concrete surfaces are exposed to view, use form ties that will leave a depression not

more than 1 inch in diameter when removed.Use water seal ties in concrete work

containing waterstops.

4. Provide form sealants and gaskets as necessary to provide tight forms.

K. Evaporation Retardant:

i. Water-based polymer, sprayable.

ii. Acceptable Products and Manufacturers:

1. "Finisher's Friend" by Century Floors.

2. "Euco-Bar" by Euclid.

3. "Confilm" by Master Builders.

L. Firm Preformed Joint Filler: ASTM D 1751, nonextruding, full depth of concrete. Sheet Materials

for Curing Concrete: ASTM C 171.

i. Synthetic Fiber/Plastic:

1. White synthetic fiber matting securely attached to white plastic sheet

backing. 2. Acceptable Product and Manufacturer: "Transguard 4000" by Fiber-Tec.

ii. Coated Burlap:

1. ASTM C 171, 10 ounce burlap with 4 mil minimum white opaque

polyethylene extruded onto burlap.

2. Acceptable Products and Manufacturers:

a. "Burlene" by Max Katz.

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b. "Cure Lap" by Midco.

N. Liquid Membrane Curing and Sealing Compound:

iii. Conform to ASTM C 1315, Type I.

iv. Styrene-acrylate or methyl-methacrylate type, 30% minimum solids content,

clear, non- yellowing, with no styrene-butadiene.

v. Acceptable Products and Manufacturers:

1. "Super Rez-Seal" by Euclid Chemical Corp.

2. "Masterkure" by Master Builders.

2.2 PROPORTIONS

A. General:

a. Use only materials and their proportions included on concrete supplier's standard

mix design forms for this Project that Engineer has given final review.

b. Measure and mix ingredients in accordance with most stringent requirements of ACI

211.1, ACI 301, and ASTM C 94.28 day minimum compressive strength as indicated

B. Workability: Must have proper consistency to be worked readily into forms and around

reinforcement without segregation, voids or, excessive bleeding.

C. Minimum Cementitious Materials Content:

i. 500 pounds per cubic yard.

D. Water/Cementitious Materials Ratio: 0.45 maximum

E. Slump:

i. Proportion concrete so slump without adding mid-range or high-range

water-reducing admixture or fibers, if used, would be as follows:

All Concrete 4 “(±1”)

ii. If high-range water-reducing admixture is used, maximum slump after

adding admixture to be 8 inches.

F. Admixtures:

i. Water-reducing admixture may be added to improve workability and reduce

water content.

ii. Mid-range or high-range water-reducing admixture may be added to

improve workability or pumpability, lower water/cement ratio, increase

ultimate strengths, and increase early strengths.

iii. Provide an air-entraining admixture where air-entrainment is specified

iv. Other admixtures may be used only with written approval of Engineer.

v. Do not use calcium chloride as an additive or in admixtures.

vi. Use admixtures in accordance with manufacturer's recommendations.

vii. Maintain air-entrainment at specified levels.

viii. In cold weather ensure that concrete strength gain is above specified

levels

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I. Fly Ash:

1. Fly ash may be used as partial replacement for Portland cement if

approved and other requirements of this Section are met.

2. If fly ash is used, ensure weight of fly ash divided by sum of cement and

fly ash weights is at least 15% and does not exceed following:

Class F Fly Ash: 20%.

2.3 MIXING

A. Ready Mix Concrete

a. Mix and transport in accordance with ASTM C 94, except as specified.

b. Reset drum revolution counter to zero on ready-mix concrete truck when water is added

to drum.

B. Site-Mixed Concrete:

1. Conform to ACI 301.

2. Use central-mix type batch plant.

2.4 FABRICATION

A. Reinforcing:

a. Fabricate reinforcing in accordance with ACI 315 and ACI SP-66, except ensure splice lengths are in accordance with ACI 318. Do not heat reinforcing bars for bending

purposes, unless otherwise allowed by Engineer.

b. Tie reinforcing bars in bundles and tag with non-rusting tags showing Shop Drawing

numbers.

PART 3 - EXECUTION

3.1 GENERAL

A. Design, construct, erect, support, and remove formwork and related items in accordance with most stringent requirements of ACI 117, 301, 318, and 347R.

B. Place reinforcing in accordance with most stringent requirements of ACI 117, 301 and 318 and

CRSI Manual of Standard Practice and Placing Reinforcing Bars.

C. Unless otherwise specified, place concrete in accordance with most stringent requirements of ACI 301 and 304R. If proportioning design mix on basis of laboratory trial batches, do not place

concrete until Engineer has reviewed results of design mix 7 day test breaks and permission is

given to proceed.

D. Ensure that all work is properly coordinated:

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1. Structural Drawings and Specifications with those of other disciplines.

2. Use final corrected Shop Drawings, placing Drawings and material/equipment Drawings.

E. Provide for concrete supplier to have quality control representative at site for concrete

placements for footings and slabs.

F. Conform to manufacturer's printed instructions for materials and equipment.

3.2 PREPARATORY WORK

A. Coarse Aggregate Base:

1. Install coarse aggregate base where shown on Drawings.

2. Compact to final thickness shown in layers not exceeding 6 inches, with minimum of 2 passes per layer with vibratory compactor.

3. Compact fill to 100% of aggregate's Standard Proctor as determined by Method D of ASTM D 698.

4. Provide dry, smooth, flat, dense surface.

B. Cleaning Equipment: Remove hardened concrete and foreign materials from mixing and

conveying equipment.

C. Formwork:

1. Unless otherwise noted on Drawings, form vertical surfaces of concrete work, except sides

of footings may be neat cut in soil if soil conditions permit.

2. Formwork for concrete surfaces to be painted or exposed to view after completion of

project to meet following requirements:

a. No dents, holes, or patches.

b. Individual formwork elements are as large as possible.

c. Position individual formwork elements in regular, uniform pattern with all joints

aligned.

d. Uniformly space and align form ties in horizontal and vertical rows.

e. Construct forms for removal without hammering or prying against concrete.

f. Temporary formwork openings (for cleaning, inspecting, etc.) are on unexposed side or constructed so that concrete surface there will match adjacent concrete in

appearance.

3. Clean all formwork.

4. Remove rust from steel formwork. 5. Solidly butt joints and provide backup at joints as required to prevent leakage of cement

paste. 6. Do not tape formwork joints unless permitted by Engineer.

7. If necessary to grease tie threads, do not allow grease to contact remainder of tie when wall

will be exposed to hydrostatic pressure.

8. Before placing reinforcing steel, thoroughly coat contact surfaces of forms with an

approved form release agent, if it is to be used.

9. Apply form release agent evenly without excess drip.

10. Do not allow form release agent to come into contact with concrete surfaces against which

fresh concrete will be placed, unless noted otherwise.

11. Moisten wood forms immediately before placing concrete where form release agents are not used.

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12. Just before placing concrete, clean forms and adjacent surfaces again as necessary. Remove

wood, sawdust, chips, dirt and other debris.

13. Provide slab side forms such that by placing a 10-foot straightedge anywhere on side of

form hitting 2 points, gap at any point between straightedge and form does not exceed 1/8

inch.

D. Reinforcing Bars:

1. Accurately place and secure reinforcement against displacement by firmly wiring at

intersections and splices with not less than No. 18 U.S. Standard Gage annealed wire, or by

use of clipping devices permitted by Engineer. 2. Turn tie wire ends away from concrete exterior.

3. Ensure reinforcing is clean, free from defects and kinks, loose mill or rust scale or coatings

that will reduce bond.

4. Protect exposed reinforcing bars, inserts and plates intended for bonding with future

expansion from corrosion by approved means.

E. Miscellaneous Items:

1. Accurately place and secure against displacement miscellaneous steel, pipe sleeves, inserts,

anchors, stair abrasive nosings, preformed joint fillers, vapor barriers, waterstops and

miscellaneous embedded items.

2. Unless noted otherwise on Drawings, ensure corner protection angles and other similar

embedded metal items are continuous from 1 concrete joint to next; if shorter lengths are

required for metal items, connect the ends by butt-welding entire joint and grinding

smooth exposed surface.

3. Temporarily fill voids in sleeves and inserts with easily removable materials.

4. Allow sufficient time between erection of forms and placing of concrete for other trades to

install and test their work.

5. Before placing concrete on grade, piping and other utilities under concrete to be inspected

and tested and excavations backfilled and properly compacted to solid bearing, as specified in Sections 02220 – Subgrade Preparation.

F. Joints:

1. Provide construction, isolation and control joints as indicated on Drawings.

G. Special Joint Preparation:

1. Where joints are subject to hydrostatic pressure and where designated on Drawings, roughen the joint surface to uniformly expose the coarse aggregate.

2. After roughening, clean the joint surface of all laitance, loose particles of aggregate or

damaged concrete. 3. Do not damage waterstop.

3.3 CONVEYING

A. General: Handle concrete from mixer to place of final deposit as rapidly as practicable and in

manner which will assure obtaining specified quality of concrete.

B. Retempering: Discard concrete which has already begun to set; do not retemper with water.

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C. Equipment: Provide mixing and conveying equipment of proper size and design to ensure a

continuous flow of concrete to delivery end. Provide conveying equipment subject to

Engineer's review. Do not use aluminum pipe or equipment in contact with concrete.

1. Mixers, agitators and non-agitating units: Conform to ASTM C 94 and current certification requirements of Department of Transportation in state where concrete plant is located.

2. Belt Conveyors:

a. Use only types which will not cause segregation.

b. Discharge runs over 30 feet into a hopper.

3. Chutes: Metal or metal lined installed at slopes not exceeding 1 vertical to 3 horizontal. Ensure chutes with greater slopes or chutes over 20 feet in length discharge into a hopper.

4. Runways:

a. Provide runways or other means above finished concrete level for wheeled conveying

equipment.

b. Do not support runways on reinforcing.

c. Do not wheel equipment directly over reinforcing or metal deck.

5. Pumps:

a. Submit to Engineer for review all changes in concrete mix to necessitate pumping.

b. Use pump hoses and other slickline components with 5 inch minimum inside

diameter, unless otherwise allowed by Engineer.

c. For slickline reducers ensure reduction in diameter is no more than 1 inch over 5-foot

length.

d. Submit to Owner's Representative method of operating pump hoses so as to prevent

displacement of reinforcing steel, dowels, form, fine aggregate base.

3.4 DEPOSITING

A. Placing:

1. General:

a. Do not deposit concrete which has partially hardened or has been contaminated by

foreign matter.

b. Deposit concrete continuously in layers of such thickness that no concrete will be

deposited on concrete which has hardened sufficiently to cause seams or planes of weakness.

c. Between construction joints place concrete in a continuous operation such that concrete is plastic at all times and flows readily into spaces between reinforcement

d. Do not subject concrete to procedures which will cause segregation.

e. Deposit concrete as near as possible to its final position.

f. Use tremies or other approved method when drops over 5 feet are required and

concrete will have to pass through obstructions, such as reinforcing.

2. Slabs on Grade: Pour slabs on grade with isolation and construction joints in locations as

shown on Drawings.

3. Do Not:

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a. Place concrete over standing water, mud, frost, ice or snow.

b. Do not use wet screeds unless permitted by Engineer.

B. Consolidation:

1. General:

a. Consolidate concrete complying with ACI 309R by vibrating, spading or rodding so

that concrete is thoroughly worked around reinforcing, and embedded items and into the corners of forms.

b. Consolidate each layer of concrete with previously placed layers in manner that will

eliminate air or stone pockets which may cause honeycombing, pitting or places of weakness.

c. Do not insert vibrator into portions of concrete that have begun to set unless allowed by Owner's Representative.

d. Do not use vibrators to transport concrete e. Keep spare vibrator on job site during concrete operations.

f. If high-range water-reducing admixture is used, do not over-vibrate concrete.

2. Formed Elements: Use internal vibrators, not form vibrators, unless allowed by Engineer.

3. Runways:

a. Consolidate runways with internal vibrators or other means allowed by Engineer.

b. Use internal vibration along construction joints. c. If bar reinforcing is used, use internal vibration around bars.

d. Do not use grate tampers, jitterbugs or mesh rollers, unless allowed by Engineer. e. Move vibrating screed, if used, steadily and as fast as practicable, keeping an

adequate surcharge of concrete at forward edge of screed. f. If high-range water-reducing admixture is to be used with vibrating screed, do not

use vibrators that are over-powered.

C. Formwork: After concrete placement, adjust forms and bracing as necessary to maintain proper

alignment and eliminate leakage of cement paste.

3.5 CONCRETE CURING

A. General:

1. Cure concrete in accordance with ACI 308, except as noted.

2. Start curing as soon as concrete surface will not be damaged by curing operations.

3. Continuously cure concrete for at least 10 consecutive days.

4. During curing period, do not allow any part of concrete to become dry.

5. Keep forms in contact with concrete wet during curing period unless type of form is

impervious to water, such as metal or fiberglass. 6. If forms are removed before curing period is complete, continue curing immediately with 1

of following methods.

B. Methods of Curing: Unless noted above, cure concrete surfaces by 1 of following materials or methods:

1. For runways, wet exposed surfaces of concrete after completing finishing and then apply prewetted burlap-polyethylene sheet conforming to ASTM C 171 with edges lapped 6

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inches minimum and sealed and secured in such manner as to prevent moisture escaping

from concrete from laps or edges. This shall be done for 7 consecutive days.

2. Liquid curing compounds sprayed or rolled uniformly in single coat on surfaces

immediately following final finishing operation.

a. Apply curing compound at coverage rate of 300 square feet maximum per gallon for broomed finish and abrasive aggregate finish.

b. For troweled finish, hard aggregate finish, and other finishes where curing

compound can be used, apply curing compound at coverage rate of 400 square feet

per gallon.

c. High solids content of curing compound may clog hand sprayers; plan for this by

using power sprayer or other approved means of application if necessary.

d. Immediately recoat, at the rate specified above, surfaces subjected to rainfall within 3 hours after compound has been applied or surfaces damaged by subsequent

construction operations within the curing period. e. Do not use liquid curing compound on at joint that we have a connection or

additional concrete

C. Concrete Protection:

1. Barricade concrete surfaces immediately after finishing.

2. Do not allow light traffic, except for curing purposes, on concrete surfaces until concrete has obtained 2,000 psi compressive strength.

3. Do not allow heavy traffic on concrete surfaces until concrete has obtained its design strength noted on Drawings, by test.

4. If concrete has been cured by water or sheet materials, permit concrete to dry minimum of 2 additional days after curing is completed before removing barricades.

5. Adequately protect concrete inserts and other embedded items from movement,

mechanical injury or from damage by elements.

3.6 FORM REMOVAL

A. General:

1. Do not remove forms until concrete has hardened sufficiently to support its own weight

and imposed construction loads.

2. Remove forms in manner to avoid damage to concrete.

B. Non-weight Supporting Forms: Formwork for columns, walls, sides of beams and other parts not supporting vertical load of concrete may be removed as soon as concrete has hardened

sufficiently to resist damage from removal operations, but in no case sooner than 12 hours.

C. Weight Supporting Forms: Do not remove formwork for bottom of beams, elevated slabs and

other parts which support vertical weight of concrete before minimum time has elapsed

recommended by ACI 347R, unless shorter time is acceptable to Engineer.

D. Reshoring: Obtain Engineer permission for early removal of weight supporting formwork and

reshoring.

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3.7 CONCRETE FINISHES

A. Runway Broomed Finishes:

1. Draw flexible bristle broom across surface to produce non-slip texture.

2. Broom in direction transverse to traffic or at right angles to slope of surface.

3.8 JOINT SEALING

A. General:

1. Seal control, isolation and construction joints with sealant as indicated on Drawings or

specified herein.

2. Unless noted otherwise, use epoxy joint sealant in control and construction joints, and use elastomeric joint sealant in isolation joints.

3. Immediately prior to sealing, clean joints to full depth of sealant in accordance with manufacturer's recommendations.

4. Remove form release agent, curing compound or other contaminants. 5. Do not allow sealant to extend over joint edges.

6. Use joint back-up material where indicated, or where recommended by sealant manufacturer.

7. Tool surface to provide smooth, attractive appearance and geometry recommended by

sealant manufacturer.

END OF SECTION 03300

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