03300_Cast-in-Place_Concrete_2026.pdf

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STANDARD SPECIFICATIONS

SECTION 03300

CAST-IN-PLACE CONCRETE AND RELATED MATERIALS

PART 1 GENERAL

1.1 DESCRIPTION

A. Section includes requirements for providing normal weight cast-in-place concrete to sizes and shapes shown.

1. See other Sections of Specifications for concrete used for other than normal weight cast-in-place concrete and for pipes and precast concrete.

1.2 DEFINITION

A. Controlled low strength material (CLSM) – commonly known as flowable fill is a self-leveling, self-compacting highly flowable and cementitious material typically composed of water, cement, fine aggregates, fly ash or other by products and used in lieu of compacted backfill.

1.3 QUALITY ASSURANCE

A. Field Requirements

1. Obtain and maintain on site a copy of ACI 301, ACI 347, ACI 350, and appropriate documents referred to therein.

2. Furnish materials and labor; make cylinders for reinforced concrete.

3. Provide visual means of identification of reinforcing steel, size, strength, and specification designation, and welded wire fabric designation, following CRSI Manual of Standard Practice.

1.4 SUBMITTALS

A. Submit following Section 01330.

1. Certified concrete mix design for each strength following ACI 301 and ACI 211.

Include dry weight of ingredients and volume of water per cubic yard of concrete.

2. Source of fly ash and mix design for CLSM.

3. Shop drawings showing reinforcing steel prepared following ACI 315, including bar lists and bending diagrams, placement drawings, and special details.

4. Drawings showing location, types, and details of joints.

5. Sequence of pours.

6. Calculations showing concrete strength to be attained at proposed time of removal of formwork, falsework, and centering.

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B. Submit following Section 01450 before delivery of materials.

1. Certified Test Reports:

a. Admixtures.

b. Aggregate.

c. Cement with percentage of alkali (Na20).

d. Copy of ASTM C1260 test with percentage of expansion due to Alkali Silica

Reaction (ASR) when alkali content in cement exceeds 0.6 percent.

e. Fly ash for CLSM showing chemical analysis, including quantity of calcium as

CaO and analytical Toxicity Characteristic Leaching Procedure (TCLP) data, establishing that fly ash is not hazardous, following 40 CFR 261.

f. Provide CLSM mix design proportions, material sources, admixtures, dry cubic yard batch weights, and test data meeting requirements specified herein.

1) Compressive Strength per ASTM D 4832

2) Flow consistency per ASTM D 6103.

3) Density per ASTM D 6023

4) Hardening time

C. Submit certified delivery tickets for concrete/CLSM furnished.

1. Name and location of batch plant and name of plant inspector.

2. Ticket number.

3. Load number (batch number).

4. Date and truck number.

5. Destination including name and location of WSSC contract.

6. Concrete type and class (strength) and design mix designation.

7. Actual quantities of all materials including admixtures and amount of concrete in cubic yards.

8. Time at which mixer drum was charged with cement.

9. Amount of free moisture by percentage of permissible mixing water in aggregates, and maximum amount of mixing water that can be added at job site to obtain specified water to cement ratio.

10. Blank space for initials of on-site receiving party.

11. Time of arrival of concrete or CLSM truck on site.

12. Time of concrete or CLSM placement.

D. Submit the following for CLSM used for abandoning pipes

1. Start station

2. End station

3. Total volume of CLSM placed.

PART 2 PRODUCTS

2.1 MATERIALS

A. Reinforcement.

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1. Reinforcing Bars: Unless otherwise indicated, ASTM A615, with minimum yield strength of 60,000 psi.

2. Welded Wire Fabric: ASTM A185, size and spacing of wires following Drawings.

3. Reinforcing Accessories: CRSI Manual of Standard Practice.

B. Fast Setting Repair Mortar:

1. Approved Products:

a. Regular applications.

1) IPA Systems Inc., Octocrete.

2) Bonsai, Inc., Blendcrete.

3) National Permacrete Company, Inc., Permacrete.

4) Chesco Creative Products, Cempatch

5) Kaufman Products, Inc., HiCap.

b. Underwater applications.

1) Elucid Chemical Co., Speedcrete Blue Line.

2) Kaufman Products, Inc., HiCap UW.

C. Non-Shrink Grout: Dry Pack Under Structure Steel and Equipment: ASTM C1107.

1. Approved Products:

a. Degussa Admixtures, Inc., Masterflow 713 grout.

b. Five Star Products Inc., Five Star Grout.

c. Euclid Chemical, NS Grout.

d. Kaufman Products, Inc., SureGrout.

e. Or equal.

D. Appurtenant Materials:

1. Vapor Barrier:

a. Building Paper: FS-UU-B-790A.

b. Polyethylene Sheeting: ASTM D2103, 6 mil thick.

2. Curing Materials:

a. Curing Compound for Concrete Surfaces: ASTM C309.

b. Sheet Materials for Curing: ASTM C171.

c. Burlap Cloth Made From Jute or Kenaf For Curing: AASHTO M182, Class 1.

3. Expansion Joint Filler:

a. Filler Not Exposed To Traffic or Weather: ASTM D994.

b. Filler Exposed To Traffic or Weather: ASTM D1751 or ASTM D1752.

4. Temporary Wood Joint Filler:

a. Straight, sound strips of width and depth shown on Drawings or as approved, to produce true, straight joint edges.

b. Tapered slightly from face-to-back and coated with paraffin, or equivalent, to seal against moisture and to promote ready removal with forms.

5. Joint Sealer:

a. Hot applied: ASTM D6690.

b. Cold applied: ASTM C920.

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6. Waterstops:

a. For expansion joints, unless otherwise shown on Drawings: Nine inches wide and minimum 3/8 inch thick, dumbbell type with center bulb of minimum 3/4 inch inside diameter.

b. For construction or control joints, unless otherwise shown on Drawings: Six inch wide and 3/8 inch thick, dumbbell type without center bulb.

c. Materials:

1) Polyvinyl chloride: U.S. Corps of Engineers Specifications, CRD C572.

2) Rubber or neoprene: U.S. Corps of Engineers Specifications, CRD C513.

d. Manufactured accessories at waterstop intersections: Form field splices with butt joints only following manufacturer's recommendations.

e. Heat-sealed field splices: Capable of developing water tightness equal to that of unspliced material and with tensile strength of not less than 50 percent of unspliced material.

7. Epoxy Bonding Compound: ASTM C881.

8. Corrosion Protection for Aluminum to be in Contact with Concrete:

a. Prepare, prime and topcoat surfaces to be coated following coating manufacturer's recommendations and apply 2 coats of:

1) Ameron Amerlock 400 Hi-Build Epoxy.

2) Tnemec Series N69 Hi-Build Epoxoline II.

3) Or equal.

b. Coating system: 10 to 16 mils DFT (dry film thickness).

E. Cement: ASTM C150, Types I and II. Utilize Type III cement only when approved by

Engineer.

F. Cement: ASTM C595, Type IL, IP and IT

G. Formwork: ACI 347 with materials suitable for use intended and adequate to support loads within tolerances as recommended.

H. Aggregates: ASTM C33.

I. Fly Ash: ASTM C618 and may be Class C or F.

J. Ground Granulated Blast-Furnace (GGBF) Slag: ASTM C-989, Grade 120.

K. Water:

1. Mixing and Curing Concrete: Clean, fresh, and free from injurious substances and shall confirm to ASTM C94.

2. Water of Questionable Quality: Meet limits of comparison tests with distilled water following AASHTO T26.

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PART 3 EXECUTION

3.1 DESIGN MIX

A. Design Strength of 28-Day Concrete:

1. Minimum 4,000 psi concrete for structurally reinforced concrete work, concrete ditches, channels, slope protection, exterior work, and flatwork underfoot, including walks, steps, ramps, drives, slabs, and floors.

2. Minimum 3,000 psi for non-reinforced concrete thrust blocking, water pipe cradle in casing or tunnels, and masonry cell fill.

3. Minimum 2,000 psi concrete for mud mats, pipe encasement and cradle, filling voids between sewer pipes and casing or tunnel liners, and for under foundations where excavated to excessive depth.

4. Minimum 2,000 psi concrete for grout with maximum size coarse aggregate not exceeding 3/8 inch.

5. Minimum 94 pounds cement per cubic yard and aggregate no larger than 1-1/2 inch for lean mix concrete for filling abandoned manholes.

6. Physical properties of CLSM shall confirm to the following:

CLSM 28-day compressive strength, (psi) D 4832

Flow consistency, (in) D 6103

Hardening time, *

ACI 229R,

Type A 40 - 80 7 – 10 3 to 5 hrs.

Type B 100– 300 > 8 < 24 hrs.

* Period of time for CLSM to reach a minimum 40 psi compressive strength.

7. Minimum density of CLSM shall be 90 pounds per cubic foot measured per ASTM D

6023.

8. Type A CLSM is for use where future excavation of CLSM may be necessary. When directed, or shown on contract plans, use Type A for pipe embedment zone, backfill for pipe crossings, limited site voids and sink holes. When directed by the engineer, Type A CLSM may be used for abandoning pipes on selected locations.

9. Type B is for use where future excavation of CLSM is not anticipated. When directed or shown on contract plans, use Type B for filling abandoned water pipes, for sewer pipes and casing or tunnel liners, manholes within paved roadway sections

a. All pipes 8 inches to 12 inches

1) 10 ft. or less in depth below roadway pavement surface or

2) below ground water table

b. Pipe greater than 12 inches at any depth below roadway pavement surface

B. Mix Proportioning:

1. 4,000 psi concrete: ACI 301, to produce watertight concrete resistant to naturally occurring or commonly used chemicals, and following:

a. Water to cement ratio: Maximum 0.45.

b. Minimum cement content and air entrainment:

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ASTM C33 Coarse Aggregate No.

Pounds/Cubic Yard Air Entrainment

467 517 5±1 percent 57 or 67 564 6±l percent

c. Slump: 1 inch minimum, 4 inches maximum.

2. Other concrete: ACI 301.

3. Substitution: GGBF Slag

a. Maximum of 50 percent of weight of cement.

b. Percentage: Establish by

1) Importance of early strength.

2) Curing temperature involved.

3) Properties of other concrete materials.

c. Minimum percentage: Determine by performing ASTM C1260 test if alkali content of cement is higher than 0.6 percent, so expansion of test mortar does not exceed

0.1 percent

d. Minimum cement content and water to cement ratio: Determine on basis of combined weight of cement and GGBF slag.

4. CLSM fill: Cement, aggregate, fly ash, and water. Proportion CLSM with sufficient amounts of Portland cement, fly ash, aggregate individually or in combination, to produce a cohesive, non-segregating mixture. Class C fly ash may replace cement.

a. Aggregate : Sand with fines content passing No. 200 sieve not exceeding 20% and/or aggregates ASTM C 33 with 3/8 inch maximum size. No clays or organics are allowed.

b. Fly ash: Maximum of 15 % by dry weight

c. Cement: up to 6% by dry weight.

d. Water: sufficient to meet flow consistency requirements

e. Admixtures: use admixtures meeting ASTM C 260 and/or C 494 as needed to improve pumpability, to control hardening time or reduce bleeding

C. Admixtures:

1. Water reducing and retarding admixtures may be used with Engineer’s approval.

Ensure compatibility of admixtures, and if retarding admixtures are used, follow form removal procedure specified below.

2. Do not use calcium chloride without prior approval.

3.2 FORMWORK DESIGN AND CONSTRUCTION

A. Design, engineer, construct, and remove formwork:

1. Chamfer exposed concrete corners of edges not less than 3/4 inch in each dimension.

2. Do not use removable form ties in water-retaining structures.

B. Design and construct to support loads following ACI 347 within tolerances specified in

ACI 301.

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C. Provide form coatings producing desired finish.

D. Schedule for Removal of Forms, Falsework, and Centering:

1. Forms, Falsework, and Centering: ACI 347.

2. Provided concrete has attained proper design strength, and Contractor meets requirements below, Engineer will approve removal of forms, falsework, and centering for:

a. Forms under unordinary conditions.

b. Concrete made with cement other than Type I or Type II.

c. Concrete made with GGBF slag.

d. Concrete made with retarders.

3. Determine concrete strength attained before removal of forms, falsework, and centering from tests of job-cured cylinders, cured under conditions not more favorable than most unfavorable conditions for portions of concrete which specimens represent.

a. Test following ASTM C31 except as modified herein.

b. Provide 3 additional cylinders for each pour or for each 1,000 square feet of form contact area, whichever is less, for testing.

1) See Section 01450.

2) Submit certified test report of cylinders to Engineer.

4. Demonstrate conclusively specified strength of concrete has been attained.

a. After removal of forms, falsework, and centering and before attainment of design strength by concrete, do not alter loading conditions to exceed permissible stresses and deformations at attained strength of concrete.

b. Minimum strength level required for each cylinder: 28 days compressive strength.

5. Immediately after forms are stripped, repair defects following ACI 301.

E. Use of earth cuts as forms for small foundations will be permitted, provided cuts are vertical, sharp, true, and with Engineer’s approval.

3.3 PLACING REINFORCEMENT

A. Unless otherwise indicated, place reinforcement following ACI 301 and with concrete cover following in ACI 318.

3.4 PLACING CONCRETE

A. Notify Engineer at least 24 hours before placing concrete.

1. Place vapor barrier under slabs poured on earth, following Drawings.

2. Wet down formwork and reinforcement before placing concrete to prevent leaching of water from concrete, but do not allow free water to stand in forms.

3. Place concrete within 90 minutes after addition of cement, aggregates, water, and admixtures.

4. Discard off-site concrete not placed within these time limits.

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5. Do not exceed the concrete free drop of 5 feet without use of adjustable length pipes.

6. Locate joints where shown on Drawings and approved submittals.

7. Seal control joints in exterior slabs.

8. When bonding new concrete to existing, prepare for subsequent placement following

ACI 301 with approved bonding compound applied and permitted to cure following manufacturer's recommendations, or as directed by Engineer.

B. Weather Conditions.

1. When air temperature has fallen to, or may be expected to fall below, 40 degrees F.

during 7-day period after placement:

a. Protect concrete work from physical damage or reduced strength caused by frost, freezing action, or low temperatures following recommendations of ACI 306 and as specified herein.

b. Provide adequate means to maintain temperature, in area where concrete is being placed, at between 50 and 70 degrees F. for at least 7 days after placement.

c. Uniformly heat water and aggregates before mixing as required to obtain concrete mixture temperature of not less than 55 degrees F. and not more than 85 degrees F.

at point of placement.

d. Provide temporary housings or coverings and maintain heat and protection to ensure that ambient temperature does not fall more than 30 degrees F. in 24 hours during 7-day period after placement.

e. Avoid rapid dry-out of concrete due to overheating, and avoid thermal shock due to sudden cooling or heating.

f. Do not place concrete on frozen subgrade or on subgrade containing frozen materials.

g. Ensure that forms, reinforcing steel, and adjacent concrete surfaces are entirely free of frost, snow, and ice before placing concrete.

h. Do not use chlorides and other materials containing antifreeze agents, or chemical accelerators, or set-control admixtures in mix designs, unless approved by Engineer in advance.

2. When Hot Weather Conditions Exist:

a. Place concrete following recommendations of ACI 305 and as specified herein.

b. Cool ingredients before mixing to maintain concrete temperature at time of placement below 80 degrees F. when temperature is rising and below 85 degrees F.

when temperature is falling.

c. Cover reinforcing steel with water-soaked burlap so steel temperature will not exceed ambient air temperature immediately before embedment in concrete.

d. Do not place concrete when hot weather conditions will cause difficulty from loss of slump, flash set, or cold joints.

e. Do not use set control admixtures in mix designs unless approved by Engineer in advance.

3.5 PLACING CLSM

A. General

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1. Control segregation of aggregate in the CLSM to produce a uniform mixture.

2. CLSM shall not be placed when the air temperature is below forty degrees Fahrenheit.

3. Place CLSM within 2 hrs. after mixing at the batch plant.

4. CLSM shall not be placed over frozen ground or ground containing frozen materials.

5. Protect CLSM fill from freezing for a period of 36 hours after placement.

B. Type A CLSM

1. When directed, use CLSM as a backfill material in pipe embedment zone, filling sink holes, or other voids.

2. Placement of CLSM may be by chutes or tremie methods in unrestricted locations with open access.

3. Pipe shall be placed level to the proper grade. Precast or other types of rigid pads that constitute a point load are not allowed underneath the pipe to maintain grade.

4. When required to prevent floatation, pipe shall be secured with anchors, weighed down or the CLSM shall be placed in lifts as required, allowing sufficient time for the initial set of the first stage before the remainder is placed.

5. Minimum cover of 2.5 ft. is required when CLSM is used as a pipe backfill material.

6. Foreign materials that falls into the trench prior to, or during placement of CLSM shall be immediately removed.

7. CLSM shall be placed under the pipe from one side so that it flows under the pipe until it appears on the other side

8. Protect exposed surfaces of CLSM fill from premature drying, washing, erosion and excessively hot or cold temperatures

9. Final backfill shall not be placed until the CLSM has reached the initial set.

C. Type B CLSM

1. When directed, abandon existing water and sewer pipes, tunnels and other voids underneath roadways, paved areas and other required locations by completely filling with CLSM.

2. Identify connections, clean debris or other obstructions that prevent CLSM placement.

3. Use tremie placement, grouting techniques, pumping or other appropriate methods to completely fill the abandoned pipes and tunnels.

4. When pumping or grouting techniques are used, monitor pressure of CLSM and prevent damage to roadway from excessive heaving and avoid damage to existing underground utilities and structures.

5. Place CLSM to fill volume between abandonment points. Continuously place CLSM with no intermediate pour points, but not exceeding 500 feet in length.

6. When the engineer determines non-complaint installation of CLSM, that does not fill voids in abandoned pipe or where voids develop due to excessive shrinkage or bleeding of CLSM, the contractor may be required to remediate using pressure grouting.

7. Plug each end of the water main being abandoned. When abandoned pipe is isolated and not connected to other lines in service, Contractor may use a temporary plug and remove plug after CLSM sets. For abandoned pipes still connected to lines in service, use permanent concrete plugs.

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3.6 CURING AND PROTECTION

A. Method of Curing and Protection: Follow ACI 301 and as required elsewhere in Contract Documents.

B. Protect structural floors left exposed to atmosphere for more than 3 days by polyethylene covering, dampened burlap, straw, or equivalent materials, as required to control hydration.

C. During hot and cold weather, cure and protect concrete as required for placing concrete herein.

D. Cure unreinforced concrete formed with earth, wood, or metal for thrust blocks, joint encasements, pipe encasements, and cradles for at least 2 hours before placing backfill.

3.7 FINISHES

A. Method of Finishing: Follow ACI 301 and as required elsewhere in Contract Documents.

B. Where not shown on Drawings, use following finishes:

1. Curbs and Equipment Bases: Rubbed finish.

2. Exterior Slabs: Broom finish, Class B tolerance.

3. Interior Slabs: Trowel finish, Class A tolerance.

4. Vault Floors: Broom finish, Class B tolerance.

5. Other Concrete Not Exposed To View: Rough form finish.

6. Other Concrete Exposed To View: Smooth form finish with voids filled and rubbed smooth.

3.8 ACCEPTANCE OF STRUCTURE

A. For sanitary engineering installations defined by ACI 350, concrete meeting acceptance criteria of ACI 301 and ACI 350 will be acceptable.

B. If concrete is cored and cores fail to meet specified 28-day strength, Engineer may reject.

C. For other structures, concrete will be acceptable if it meets acceptance criteria of ACI 301.

D. Engineer: Sole judge of whether concrete meets requirements.

E. Remove, dispose of, and replace concrete not meeting specified requirements at no cost to the Commission.

F. Make repairs using approved repair procedure in Engineer's presence.

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PART 4 MEASUREMENT AND PAYMENT

4.1 Measurement of concrete work for payment will not be made under this Section. Concrete work is considered essential material required in construction of specific items of work that will be measured and paid for under various items or lump sums listed in Bid Schedule.

**WSSC**