Specification Section 03 31 01.00 10.pdf

Montgomery L/D Dam Gate Installation 2020

SECTION TABLE OF CONTENTS

DIVISION 03 - CONCRETE

SECTION 03 31 01.00 10

CAST-IN-PLACE STRUCTURAL CONCRETE FOR CIVIL WORKS

PART 1 GENERAL

1.1 REFERENCES

1.2 DESIGN REQUIREMENTS

1.2.1 Air Content

1.2.2 Slump

1.2.3 Concrete Proportioning

1.2.4 Required Average Compressive Strength

1.2.4.1 Average Compressive Strength from Test Records

1.2.4.2 Average Compressive Strength without Previous Test Records

1.2.5 Concrete Strength

1.2.6 Maximum Water-Cement (W/C) Ratio

1.2.7 Standard PennDOT Mixture Design

1.2.8 Construction Tolerances

1.2.8.1 Appearance

1.3 SUBMITTALS

1.4 CONCRETE PLACEMENT PLAN

1.5 QUALITY ASSURANCE

1.5.1 Concrete Strength

1.6 DELIVERY, STORAGE, AND HANDLING

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 Cementitious Materials

2.1.1.1 Portland Cement

2.1.1.2 Pozzolan, Other than Silica Fume

2.1.1.3 Silica Fume

2.1.2 Aggregates

2.1.2.1 General

2.1.2.2 Concrete Aggregate Sources

2.1.2.3 Alkali-Silica Reactivity

2.1.3 Chemical Admixtures

2.1.3.1 Air-Entraining Admixture

2.1.3.2 Accelerating Admixture

2.1.3.3 Water-Reducing or Retarding Admixture

2.1.3.4 Other Chemical Admixtures

2.1.4 Curing Materials

2.1.4.1 Membrane-Forming Curing Compound

2.1.4.2 Impervious-Sheet Curing Materials

2.1.4.3 Burlap

2.1.5 Water

2.1.6 Non-shrink Grout

2.1.7 Non-shrink Epoxy Grout

2.1.8 Latex Bonding Compound

2.1.9 Epoxy Bonding Agent

2.2 EQUIPMENT

2.2.1 Concrete Mixers

SECTION 03 31 01.00 10 Page 1 Certified Final Documents RTA - W911WN20B8003 - Amendment 0001

2.2.1.1 Truck Mixers

2.2.2 Conveying Equipment

2.2.2.1 Buckets

2.2.2.2 Transfer Hoppers

2.2.2.3 Trucks

2.2.2.4 Chutes

2.2.2.5 Belt Conveyors

2.2.2.6 Concrete Pumps

2.2.3 Vibrators

2.2.4 Batch Tickets

PART 3 EXECUTION

3.1 PREPARATION FOR PLACING

3.1.1 Embedded Items

3.1.2 Concrete on Existing Concrete

3.1.3 Roughening of Concrete Surfaces to Receive Fresh Concrete

3.1.4 Construction Joint Treatment

3.1.4.1 Joint Preparation

3.1.4.2 High-Pressure Water Jet

3.1.4.3 Wet Sandblasting

3.1.4.4 Waste Disposal

3.2 PLACING

3.2.1 General

3.2.2 Ambient Conditions

3.2.3 Placing Procedures

3.2.4 Placement by Pump

3.2.5 Cold-Weather Placing

3.2.6 Hot-Weather Placing

3.2.7 Consolidation

3.3 FINISHING

3.3.1 Unformed Surfaces

3.3.1.1 Float Finish

3.3.1.2 Trowel Finish

3.3.2 Formed Surfaces

3.3.3 Formed Surface Repair

3.3.3.1 Class A Finishes

3.3.3.2 Material and Procedure for Repairs

3.4 CURING AND PROTECTION

3.4.1 Duration

3.4.2 Moist Curing

3.4.3 Cold Weather Curing and Protection

3.5 SETTING OF BASE PLATES AND BEARING PLATES

3.5.1 Setting of Plates

3.5.2 Non-shrink Grout Application

3.5.2.1 Mixing and Placing of Non-shrink Grout

3.5.2.2 Treatment of Exposed Surfaces

3.5.2.3 Curing

3.6 TESTS AND INSPECTIONS

3.6.1 General

3.6.2 Concrete Technicians

3.6.3 Preparation for Placing

3.6.3.1 Compressive Strength

3.6.3.2 Air Content

3.6.3.3 Slump

3.6.3.4 Temperature

3.6.3.5 Consolidation and Protection

3.6.4 Action Required

3.6.4.1 Placing

SECTION 03 31 01.00 10 Page 2

3.6.4.2 Air Content

3.6.4.3 Slump

3.6.5 Reports

-- End of Section Table of Contents --

SECTION 03 31 01.00 10 Page 3

SECTION 03 31 01.00 10

CAST-IN-PLACE STRUCTURAL CONCRETE FOR CIVIL WORKS

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

AMERICAN CONCRETE INSTITUTE (ACI)

ACI 117 (2010; Errata 2011) Specifications for Tolerances for Concrete Construction and Materials and Commentary

ACI 211.1 (1991; R 2009) Standard Practice for Selecting Proportions for Normal, Heavyweight and Mass Concrete

ACI 214R (2011) Evaluation of Strength Test Results of Concrete

ACI 305R (2010) Guide to Hot Weather Concreting

AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

(AASHTO)

AASHTO M 182 (2005; R 2017) Standard Specification for Burlap Cloth Made from Jute or Kenaf and Cotton Mats

ASTM INTERNATIONAL (ASTM)

ASTM C1017/C1017M (2013; E 2015) Standard Specification for Chemical Admixtures for Use in Producing Flowing Concrete

ASTM C1059/C1059M (2013) Standard Specification for Latex Agents for Bonding Fresh to Hardened Concrete

ASTM C1064/C1064M (2017) Standard Test Method for Temperature of Freshly Mixed Hydraulic-Cement Concrete

ASTM C1077 (2017) Standard Practice for Agencies Testing Concrete and Concrete Aggregates for Use in Construction and Criteria for Testing Agency Evaluation

ASTM C1107/C1107M (2017) Standard Specification for Packaged Dry, Hydraulic-Cement Grout (Nonshrink)

SECTION 03 31 01.00 10 Page 4

ASTM C1240 (2014) Standard Specification for Silica Fume Used in Cementitious Mixtures

ASTM C1260 (2014) Standard Test Method for Potential Alkali Reactivity of Aggregates (Mortar-Bar Method)

ASTM C143/C143M (2015) Standard Test Method for Slump of Hydraulic-Cement Concrete

ASTM C150/C150M (2018) Standard Specification for Portland Cement

ASTM C1567 (2013) Standard Test Method for Potential Alkali-Silica Reactivity of Combinations of Cementitious Materials and Aggregate (Accelerated Mortar-Bar Method)

ASTM C171 (2016) Standard Specification for Sheet Materials for Curing Concrete

ASTM C172 (2010) Standard Practice for Sampling Freshly Mixed Concrete

ASTM C192/C192M (2018) Standard Practice for Making and Curing Concrete Test Specimens in the Laboratory

ASTM C231/C231M (2017a) Standard Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method

ASTM C260/C260M (2010a; R 2016) Standard Specification for Air-Entraining Admixtures for Concrete

ASTM C309 (2011) Standard Specification for Liquid Membrane-Forming Compounds for Curing Concrete

ASTM C31/C31M (2019) Standard Practice for Making and Curing Concrete Test Specimens in the Field

ASTM C33/C33M (2018) Standard Specification for Concrete Aggregates

ASTM C39/C39M (2018) Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens

ASTM C494/C494M (2017) Standard Specification for Chemical Admixtures for Concrete

ASTM C618 (2019) Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete

ASTM C881/C881M (2015) Standard Specification for Epoxy-Resin-Base Bonding Systems for

SECTION 03 31 01.00 10 Page 5

Concrete

ASTM C94/C94M (2018) Standard Specification for Ready-Mixed Concrete

ASTM D75/D75M (2014) Standard Practice for Sampling Aggregates

PENNSYLVANIA DEPARTMENT OF TRANSPORTATION (PDT)

PDT 34 Bulletin 14, Aggregate Producers

PDT 408 (2016) Specifications

PDT 42 Bulletin 42, Concrete

U.S. ARMY CORPS OF ENGINEERS (USACE)

COE CRD-C 400 (1963) Requirements for Water for Use in Mixing or Curing Concrete

COE CRD-C 521 (1981) Standard Test Method for Frequency and Amplitude of Vibrators for Concrete

1.2 DESIGN REQUIREMENTS

For each portion of the structure, select concrete mixture proportions so that the strength and W/C requirements are met. The concrete mixture quantities of all ingredients per cubic yard and nominal maximum coarse aggregate size that will be used in the manufacture of each quality of concrete shall be stated. Proportions shall indicate the mass of cement, pozzolan, and water; the mass of aggregates in a saturated surface-dry condition; and the quantities of admixtures. Nominal maximum-size coarse aggregate shall be 3/4 inch. The concrete mixture design is the responsibility of the Contractor and shall be submitted to the Contracting Officer or their designated representative for Approval.

1.2.1 Air Content

Air content as delivered to the forms and as determined by ASTM C231/C231M shall be between 4.5 and 7.5 percent.

1.2.2 Slump

The slump shall be determined in accordance with ASTM C143/C143M and shall be within the range of 1 to 4 inches prior to addition of water reducing admixtures. After addition of admixtures, the slump shall not exceed 7 inches . Where placement by pump is approved, the slump shall not exceed 6 inches.

1.2.3 Concrete Proportioning

Trial batches and testing requirements for various qualities of concrete specified are the responsibility of the Contractor. Obtain samples of aggregates in accordance with the requirements of ASTM D75/D75M. Samples of materials other than aggregate shall be representative of those proposed for the project and shall be accompanied by the manufacturer's test reports indicating compliance with applicable specified requirements. Make trial mixtures having proportions, consistencies, and

SECTION 03 31 01.00 10 Page 6 air content suitable for the work based on methodology described in ACI 211.1 , using at least three different water-cement ratios, which will produce a range of strength encompassing those required for the work. The maximum water-cement ratios required in paragraph MAXIMUM WATER-CEMENT (W/C) RATIO below, will be converted to a weight ratio of water to cement plus pozzolan by mass, silica fume, or GGBF slag by mass equivalency as described in ACI 211.1 . In the case where GGBF slag is used, include the weight of the slag in the equations for the term P, which is used to denote the mass of pozzolan. If pozzolan is used in the concrete mixture, the minimum pozzolan content shall be 15 percent of the total cementitious material. Proportion trial mixtures for maximum permitted slump and air content with due consideration to the approved conveying and placement method. The temperature of concrete in each trial batch shall be reported. For each water-cement ratio, at least three test cylinders for each test age shall be made and cured in accordance with ASTM C192/C192M;

they shall be tested at 7 days and at the design age specified in accordance with ASTM C39/C39M. From these test results, a curve will be plotted showing the relationship between water-cement ratio and strength.

1.2.4 Required Average Compressive Strength

In meeting the strength requirements specified below, the selected mixture proportion shall produce a required average compressive strength f'cr exceeding the specified strength f'c by the amount indicated below.

1.2.4.1 Average Compressive Strength from Test Records

Where a concrete production facility has test records, establish a standard deviation in accordance with the applicable provisions of ACI 214R .

Test records from which a standard deviation is calculated shall represent materials, quality control procedures, and conditions similar to those expected, shall represent concrete produced to meet a specified strength or strengths (f'c) within 1,000 psi of that specified for proposed work, and shall consist of at least 30 consecutive tests. A strength test shall be the average of the strengths of two cylinders made from the same sample of concrete and tested at 28 days or at another test age designated for determination of f'c. Required average compressive strength f'cr used as the basis for selection of concrete proportions shall be the larger of the equations that follow using the standard deviation as determined above:

f'cr = f'c + 1.34S f'cr = f'c + 2.33S - 500

Where S = standard deviation

Where a concrete production facility does not have test records meeting the requirements above but does have a record based on 15 to 29 consecutive tests, a standard deviation shall be established as the product of the calculated standard deviation and a modification factor from the following table:

NUMBER OF TESTS* MODIFICATION FACTOR FOR STANDARD DEVIATION

less than 15 Use tabulation in paragraph REQUIRED AVERAGE

COMPRESSIVE STRENGTH

SECTION 03 31 01.00 10 Page 7

NUMBER OF TESTS* MODIFICATION FACTOR FOR STANDARD DEVIATION

15 1.16

20 1.08

25 1.03

30 or more 1.00

*Interpolate for intermediate numbers of tests.

1.2.4.2 Average Compressive Strength without Previous Test Records

When a concrete production facility does not have sufficient field strength test records for calculation of the standard deviation, determine the required average strength fcr as follows:

If the specified compressive strength f'c is 3,000 to 5,000 psi, f'cr = f'c + 1,200

1.2.5 Concrete Strength

Specified compressive strength f'c shall be as follows:

COMPRESSIVE STRENGTH (PSI) STRUCTURE OR PORTION OF STRUCTURE

4,000 @ 28 days All cast-in-place concrete

1.2.6 Maximum Water-Cement (W/C) Ratio

Maximum W/C shall be as follows:

WATER-CEMENT RATIO,

BY MASS

STRUCTURE OR PORTION OF STRUCTURE

0.43 All cast-in-place concrete

These W/C's may cause higher strengths than that required by paragraph

CONCRETE STRENGTH.

1.2.7 Standard PennDOT Mixture Design

A standard PDT 408 , Section 704, Class AAA concrete may be considered acceptable upon meeting all requirements of this specification section.

1.2.8 Construction Tolerances

Except as otherwise specified herein or noted on the drawings, tolerances for concrete construction as well as definition of terms and application practices shall be in accordance with ACI 117 . Tolerances are not cumulative. The most restrictive tolerance controls. Tolerances of the pier modifications and sills containing steel embedments shall not be less restrictive than the tolerances required by steel embedments in Section

05 50 14.00 08 METALWORK FABRICATION, MACHINE WORK, MISCELLANEOUS

PROVISIONS.

SECTION 03 31 01.00 10 Page 8

When forms or shoring are used, the measurements shall be made prior to removal. Except as specified otherwise, plus tolerance increases the amount or dimension to which it applies, or raises a level alignment and minus tolerance decreases the amount or dimension to which it applied, or lowers a level alignment. A tolerance without sign means plus or minus.

Where only one signed tolerance is specified, there is no specified tolerance in the opposing direction.

1.2.8.1 Appearance

Permanently exposed surfaces shall be cleaned, if stained or otherwise discolored, by a method that does not harm the concrete and that is approved by the Contracting Officer or their designated representative.

1.3 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. Submit the following in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-01 Preconstruction Submittals

Concrete Placement Plan; G, RO

SD-02 Shop Drawings

Installation Drawings; G, RO

SD-03 Product Data

Concrete Mixture Proportions; G, RO

Concrete mixture proportions as determined by the Contractor and submitted for review. The submission shall be accompanied by test reports form a laboratory complying with ASTM C1077 showing that proportions thus selected will produce concrete of the qualities indicated. No substitution shall be made in the source of type of materials used in the work without additional tests to show that the quality of the new materials and concrete are satisfactory.

Batch Tickets Air-Entraining Admixture; G, RO Other Chemical Admixtures; G, RO Latex Bonding Compound; G, RO Epoxy Bonding Agent; G, RO Non-shrink Grout; G, RO Non-shrink Epoxy Grout; G, RO

Provide manufacturer's catalog data.

Testing Technicians; G, RO Concrete Construction Inspector (CCI); G, RO

Statements that the concrete testing technician and the concrete inspectors meet the specified requirements.

Construction Joint Treatment; G, RO

SECTION 03 31 01.00 10 Page 9

The method and equipment proposed for joint cleanup and waste disposal, for review and approval.

Curing and Protection; G, RO

The curing medium and methods to be used for review and approval.

Cold-Weather Placing; G, RO

The proposed materials, methods, and protection for approval, if concrete is to be placed under cold-weather conditions.

Hot-Weather Placing; G, RO

The proposed materials, methods, and protection for approval, if concrete is to be placed under hot-weather conditions.

SD-06 Test Reports

Tests And Inspections

Aggregates

Submit test results for aggregates in accordance with ASTM C1260 for potential alkali-silica reactions.

SD-07 Certificates

Cementitious Materials

Mill test reports attesting that materials meet the requirements of the specification under which they are furnished. Certification and mill test reports shall be from samples taken from the particular lot furnished.

Impervious-Sheet Curing Materials

Impervious-sheet curing materials certified for compliance with all specification requirements.

1.4 CONCRETE PLACEMENT PLAN

A plan shall be submitted to the Contracting Officer or their designated representative for comment and approval. The plan shall include proposed placing equipment and procedures. The plant shall also address cold-weather placing and hot-weather placing in accordance with paragraph Placing Procedures.

1.5 QUALITY ASSURANCE

The Government will sample and test aggregates and concrete to determine compliance with the specifications. Provide facilities and labor as may be necessary for procurement of representative test samples. Samples of aggregates will be obtained at the point of batching in accordance with ASTM D75/D75M. Concrete will be sampled in accordance with ASTM C172. No material shall be used until notice has been given by the Contracting Officer or their designated representative that test results are satisfactory. The individuals who sample and test concrete or the

SECTION 03 31 01.00 10 Page 10 constituents of concrete as required in this specification shall have demonstrated a knowledge and ability to perform the necessary test procedures equivalent to the ACI minimum guidelines for certification of Concrete Field Testing Technicians, Grade I. The individuals who perform the inspection of concrete construction shall have demonstrated a knowledge and ability equivalent to the ACI minimum guidelines for certification of Concrete Construction Inspector (CCI). Indicate specific locations of concrete placement, forms, and steel reinforcement on installation drawings. Drawings shall include, but not be limited to, square footage of concrete placement, thickness, and width, plan dimensions, and arrangement of cast-in-place section.

1.5.1 Concrete Strength

Compressive strength test specimens will be made by the Government and cured in accordance with ASTM C31/C31M and tested in accordance with ASTM C39/C39M. The strength of the concrete will be considered satisfactory so long as the average of all sets of three consecutive test results equals or exceeds the specified compressive strength f'c and no individual test result falls below the specified strength f'c by more than 500 psi. A "test" is defined as the average of two companion cylinders, or if only one cylinder is tested, the results of the single cylinder test. Additional analysis or testing, including nondestructive testing, taking cores and/or load tests may be required at the Contractor's expense when the strength of the concrete in the structure is considered potentially deficient.

1.6 DELIVERY, STORAGE, AND HANDLING

Chemical admixtures that have been in storage at the project site for longer than 6 months or that have been subjected to freezing shall be retested at the expense of the Contractor when directed by the Contracting Officer or their designated representative and rejected if test results are not satisfactory. Chemical admixtures will be accepted based on compliance with the requirements of paragraph CHEMICAL ADMIXTURES in Part 2.

PART 2 PRODUCTS

2.1 MATERIALS

Submit manufacturer's literature from suppliers which demonstrates compliance with applicable specifications for the specified materials

2.1.1 Cementitious Materials

Cementitious materials shall be portland cement, portland cement in combination with pozzolan or portland cement in combination with silica fume conforming to appropriate specifications listed below. Use of cementitious materials in architectural concrete shall be restricted to one color, one source, and one type. Submit manufacturer's certificates of compliance, accompanied by mill test reports, attesting that the concrete materials meet the requirements of the specifications.

2.1.1.1 Portland Cement

ASTM C150/C150M, Type I or II, low alkali.

SECTION 03 31 01.00 10 Page 11

2.1.1.2 Pozzolan, Other than Silica Fume

Pozzolan shall conform to ASTM C618, Class C or F, with the optional requirements for multiple factor, drying shrinkage, and uniformity of Table 2A. Table 1A requirement for maximum alkalies shall apply when used with aggregates listed at the end of this section to require low-alkali cement.

2.1.1.3 Silica Fume

Silica fume may be furnished as a dry, densified material or as a slurry.

Silica fume, unprocessed, or before processing into a slurry or a densified material, shall conform to ASTM C1240 with Table 2 and the Specific Surface Area and Uniformity Requirements in Table 4 invoked. The Contractor shall provide, at it's own expense, the services of a manufacturer's technical representative, experienced in mixture proportioning, placement procedures, and curing of concrete containing silica fume. The manufacturer's representative shall be available for consultation by both the Contractor and the Government during mixture proportioning, planning, and production of silica-fume concrete and shall be onsite immediately prior to and during at least the first placement of concrete containing silica fume, and at other times if directed.

2.1.2 Aggregates

2.1.2.1 General

Concrete aggregates may be furnished from any source listed in PDT 34 capable of meeting the quality requirements below. Fine and coarse aggregates shall conform to the grading requirements of ASTM C33/C33M.

Where the use of highway department gradations are permitted, proposed gradations shall be submitted for approval.

2.1.2.2 Concrete Aggregate Sources

a. List of Sources - The concrete aggregates sources may be selected from sources listed in PDT 34 .

b. Selection of Source - After the award of the contract, designate in writing only one source or combination of sources from which to furnish aggregates.

2.1.2.3 Alkali-Silica Reactivity

Evaluate and test fine and coarse aggregates to be used in all concrete for alkali-aggregate reactivity in accordance with ASTM C1260. Test both coarse aggregate size groups if from different sources. Evaluate the fine and coarse aggregates separately and in combination, which matches the Contractor's proposed mix design proportioning. Test results of the combination must have a measured expansion less than 0.08 percent at 16 days after casting.

a. If the test data indicates expansion of 0.08 percent or greater, the aggregate shall be rejected or perform additional testing shall be performed using ASTM C1567 and using the proposed mix design. Utilize the Contractor's proposed low alkali portland cement and Class F fly ash or Class N pozzolan in combination with the proposed aggregate percentage for the test proportioning. Use Class F fly ash or Class N pozzolan in the range of 15 percent to 25 percent of the total

SECTION 03 31 01.00 10 Page 12 cementitious material by mass. Determine the quantity that will meet all the requirements of these specifications and that will lower the expansion less than 0.08 percent at 16 days after casting in accordance with ASTM C1567. Class C fly ash shall not be used with reactive aggregates.

If any of the above options does not lower the expansion to less than 0.08 percent at 16 days after casting, reject the aggregate(s) and submit new aggregate sources for retesting. Submit the results of testing to the Contracting Officer or their designated representative for evaluation and acceptance.

2.1.3 Chemical Admixtures

Chemical admixtures to be used, when required or permitted, shall conform to the appropriate specification listed. Retest chemical admixtures that have been in storage at the project site for longer than 6 months or that have been subjected to freezing at the request of the Contracting Officer or their designated representative and at the expense of the Contractor.

Chemical admixtures shall be rejected if test results are not satisfactory.

2.1.3.1 Air-Entraining Admixture

The air-entraining admixture shall conform to ASTM C260/C260M and shall consistently cause the concrete to have an air content in the specified ranges under field conditions.

2.1.3.2 Accelerating Admixture

Accelerators shall meet the requirements of ASTM C494/C494M, Type C or E, except that calcium chloride or admixtures containing calcium chloride shall not be used.

2.1.3.3 Water-Reducing or Retarding Admixture

a. Water-Reducing or Retarding Admixtures: ASTM C494/C494M, Type A, B, or D, except that the 6-month and 1-year compressive strength tests are waived.

b. High-Range Water Reducing Admixture: ASTM C494/C494M, Type F or G except that the 6-month and 1-year strength requirements shall be waived. The admixture may be used only when approved by the Contracting Officer or their designated representative, such approval being contingent upon particular mixture control as described in the Contractor's Quality Control Plan.

2.1.3.4 Other Chemical Admixtures

Other chemical admixtures for use in producing flowing concrete shall comply with ASTM C1017/C1017M , Type 1 or 2. These admixture shall be used only for concrete listed in paragraph SLUMP.

2.1.4 Curing Materials

Provide curing material conforming to the following requirements:

2.1.4.1 Membrane-Forming Curing Compound

ASTM C309, Type 1-D or 2. Nonpigmented compound shall contain a fugitive

SECTION 03 31 01.00 10 Page 13 dye and shall have the reflected requirements in ASTM C309 waived.

2.1.4.2 Impervious-Sheet Curing Materials

Impervious-sheet curing materials shall conform to ASTM C171, type optional, except polyethylene film shall not be used.

2.1.4.3 Burlap

Burlap used for curing shall conform to AASHTO M 182.

2.1.5 Water

Water for mixing and curing shall be fresh, clean, potable, and free of injurious amounts of oil, acid, salt, or alkali, except that nonpotable water may be used if it meets the requirements of COE CRD-C 400 .

2.1.6 Non-shrink Grout

Non-shrink grout shall conform to ASTM C1107/C1107M , non-metallic, and shall be a commercial formulation suitable for the application proposed.

Grout shall have a minimum 28 day compressive strength of 5,000 psi.

2.1.7 Non-shrink Epoxy Grout

Non-shrink epoxy grout shall conform to ASTM C881/C881M, Type V, Grade 2 with mineral filler, and shall be a commercial formulation suitable for the application proposed.

2.1.8 Latex Bonding Compound

Latex bonding compound agents for bonding fresh to hardened concrete for repairs and areas as indicated on the drawings shall conform to

ASTM C1059/C1059M .

2.1.9 Epoxy Bonding Agent

ASTM C881/C881M, Type II or V. Type II material for non-loadbearing applications. Type V material for load bearing applications.

2.2 EQUIPMENT

The concrete shall be produced in a plant listed in PDT 42 .

2.2.1 Concrete Mixers

The concrete mixers shall not be charged in excess of the capacity recommended by the manufacturer. The mixers shall be operated at the drum or mixing blade speed designated by the manufacturer. Maintain the mixers in satisfactory operating condition, and keep the mixer drums free of hardened concrete. Should any mixer at any time produce unsatisfactory results, promptly discontinue its use until it is repaired.

2.2.1.1 Truck Mixers

Truck mixers, the mixing of concrete therein, and concrete uniformity shall conform to the requirements of ASTM C94/C94M. A truck mixer may be used either for complete mixing (transit-mixed) or to finish the partial mixing done in a stationary mixer (shrink-mixed). Equip each truck with

SECTION 03 31 01.00 10 Page 14 two counters from which it will be possible to determine the number of revolutions at mixing speed and the number of revolutions at agitating speed.

2.2.2 Conveying Equipment

The conveying equipment shall conform to the following requirements:

2.2.2.1 Buckets

The interior hopper slope shall be not less than 58 degrees from the horizontal, the minimum dimension of the clear gate opening shall be at least five times the nominal maximum-size aggregate, and the area of the gate opening shall not be less than 2 square feet. The maximum dimension of the gate opening shall not be greater than twice the minimum dimension. The bucket gates shall be essentially grout tight when closed and may be manually, pneumatically, or hydraulically operated except that buckets larger than 2 cubic yards shall not be manually operated. The design of the bucket shall provide means for positive regulation of the amount and rate of deposit of concrete in each dumping position.

2.2.2.2 Transfer Hoppers

Concrete may be charged into nonagitating hoppers for transfer to other conveying devices. Transfer hoppers shall be capable of receiving concrete directly from delivery vehicles and have conical-shaped discharge features. The transfer hopper shall be equipped with a hydraulically operated gate and with a means of external vibration to effect complete discharge. Concrete shall not be held in nonagitating transfer hoppers more than 30 minutes.

2.2.2.3 Trucks

Truck mixers operating at agitating speed or truck agitators used for transporting plant-mixed concrete shall conform to the requirements of ASTM C94/C94M. Nonagitating equipment may be used for transporting plant-mixed concrete over a smooth road when the hauling time is less than 15 minutes. Bodies of nonagitating equipment shall be smooth, watertight, metal containers specifically designed to transport concrete, shaped with rounded corners to minimize segregation, and equipped with gates that will permit positive control of the discharge of the concrete.

2.2.2.4 Chutes

When concrete can be placed directly from a truck mixer, agitator, or nonagitating equipment, the chutes attached to this equipment by the manufacturer may be used. A discharge deflector shall be used when required by the Contracting Officer or their designated representative.

Separate chutes and other similar equipment will not be permitted for conveying concrete.

2.2.2.5 Belt Conveyors

Belt conveyors shall be designed and operated to assure a uniform flow of concrete from mixer to final place of deposit without segregation of ingredients or loss of mortar and shall be provided with positive means for preventing segregation of the concrete at the transfer points and the point of placing. Belt conveyors shall be constructed such that the idler spacing shall not exceed 36 inches. The belt speed shall be a minimum of

SECTION 03 31 01.00 10 Page 15

300 feet per minute and a maximum of 750 feet per minute. If concrete is to be placed through installed horizontal or sloping reinforcing bars, the conveyor shall discharge concrete into a pipe or elephant trunk that is long enough to extend through the reinforcing bars.

2.2.2.6 Concrete Pumps

Concrete may be conveyed by positive displacement pump when approved. The pumping equipment shall be piston or squeeze pressure. The pipeline shall be rigid steel pipe or heavy-duty flexible hose. The inside diameter of the pipe shall be at least three times the nominal maximum-size coarse aggregate in the concrete mixture to be pumped but not less than 4 inches.

Aluminum pipe shall not be used.

2.2.3 Vibrators

Vibrators of the proper size, frequency, and amplitude shall be used for the type of work being performed in conformance with the following requirements:

APPLICATION HEAD DIAMETER Inches FREQUENCY

(VPM)

AMPLITUDE Inches

Thin walls, beams, etc.

1-1/4 to 2-1/2 9,000 to 13,500 0.02 to 0.04

General construction 2 to 3-1/2 8,000 to 12,000 0.025 to 0.05

The frequency and amplitude shall be determined in accordance with

COE CRD-C 521 .

2.2.4 Batch Tickets

Approved batch tickets shall be furnished for each load of ready-mixed concrete.

PART 3 EXECUTION

3.1 PREPARATION FOR PLACING

3.1.1 Embedded Items

Before placement of concrete, take care to determine that all embedded items are firmly and securely fastened in place as indicated on the drawings, or required. Embedded items shall be free of oil and other foreign matter such as loose coatings or rust, paint, and scale. The embedding of wood in concrete will be permitted only when specifically authorized or directed. Voids in sleeves, inserts, and anchor slots shall be filled temporarily with readily removable materials to prevent the entry of concrete into voids. Welding, including tack welding, will not be permitted on embedded metals within 2 feet of the surface of the concrete.

3.1.2 Concrete on Existing Concrete

Existing concrete surfaces upon which concrete is to be placed shall be clean, free from oil, standing or running water, ice, mud, coating, and debris. Immediately before the concrete is placed, all existing concrete

SECTION 03 31 01.00 10 Page 16 surfaces shall be clean thoroughly by high-pressure water jet. All concrete surfaces shall be kept continuously wet without standing water immediately prior to placing concrete.

3.1.3 Roughening of Concrete Surfaces to Receive Fresh Concrete

Surfaces of concrete exposed during removal shall be roughened once the limits of removal are approved by the Contracting Officer or their designated representative. The roughening shall be conducted prior to installation of embedded dowels or setting of embedded components.

Surfaces that are left sufficiently roughed by the removal process will not require additional roughening. However, smooth concrete surfaces resulting from precision removal methods (i.e. wire saws) shall be roughened with small hand held tools or pneumatic tools not weighing more than 15 pounds. The roughening process shall not extend any deeper than an additional 1/2 inch with an amplitude of 1/4 inch and shall be completed over all smooth concrete surfaces to which fresh concrete is to bond. The Contractor shall demonstrate to the Contracting Officer or their designated representative the procedures and equipment that will be used prior to proceeding. A small area of concrete will be selected by the Contracting Officer or their designated representative for this demonstration to take place.

3.1.4 Construction Joint Treatment

Submit the method and equipment proposed for joint cleanup and waste disposal, for review and approval. Construction joint treatment shall conform to the following requirements:

3.1.4.1 Joint Preparation

Concrete surfaces to which additional concrete is to be bonded shall be prepared for receiving the next lift or adjacent concrete by cleaning with either sandblasting, high-pressure water jet, or other approved method.

Air-water cutting will not be permitted. Regardless of the method used, the resulting surfaces shall be free from all laitance and inferior concrete so that clean, well bonded coarse aggregate is exposed uniformly throughout the lift surface. The edges of the coarse aggregate shall not be undercut. The surface shall be washed clean again as the last operation prior to placing the next lift. There shall be no standing water on the surface upon which concrete is placed.

3.1.4.2 High-Pressure Water Jet

A stream of water under a pressure of not less than 3,000 psi may be used for cleaning. Its use shall be delayed until the concrete is sufficiently hard so that only the surface skin or mortar is removed and there is no undercutting of coarse-aggregate particles. If the water jet is incapable of a satisfactory cleaning, the surface shall be cleaned by sandblasting.

3.1.4.3 Wet Sandblasting

This method may be used when the concrete has reached sufficient strength to prevent undercutting of the coarse aggregate particles. The surface of the concrete shall then be washed thoroughly to remove all loose materials.

3.1.4.4 Waste Disposal

The method used in disposing of waste water employed in cutting, washing, SECTION 03 31 01.00 10 Page 17 and rinsing of concrete surfaces shall be such that the waste water does not stain, discolor, or affect exposed surfaces of the structures, or damage the environment of the project area. The Contractor shall collect waste water to the extent practicable. See Section 01 57 19.00 08 TEMPORARY ENVIRONMENTAL CONTROLS. The method of disposal shall be subject to approval.

3.2 PLACING

3.2.1 General

Concrete shall be handled from mixer to transporting unit to the point of placement in a continuous manner. Concrete shall be placed without permitting the material to segregate. Adequate platforms, scaffolding, ramps, and walkways shall be provided so that personnel and equipment are not supported by in-place reinforcement. Placing will not be permitted when the sun, heat, wind, or limitations of facilities furnished by the Contractor prevent proper placement, consolidation, finishing and curing.

Sufficient placing capacity shall be provided so that concrete can be kept free of cold joints. Maintain specified slump and temperature limits throughout duration of placement.

3.2.2 Ambient Conditions

Concrete placement shall not be permitted when weather conditions prevent proper placement and consolidation, or when conditions will adversely affect the quality of the concrete. Unless otherwise specified or approved, the ambient temperature of the placement area and all surfaces to receive concrete shall be above 32 degrees F. In hot weather, forms, reinforcement, and conveying and placement equipment shall be cooled, if necessary, to achieve the specific concrete temperature.

Concrete shall be maintained at a temperature above 40 degrees F for the first 7 days following placement and above 32 degrees F for the remainder of the specified curing period.

3.2.3 Placing Procedures

The surfaces of horizontal construction joints shall be kept continuously wet for the first 12 hours during the 24-hour period prior to placing concrete. Surfaces may be dampened immediately before placement if necessary. Deposit concrete as close as possible to its final position in the forms and, in so depositing, there shall be no vertical drop greater than 5 feet except where suitable equipment is provided to prevent segregation and where specifically authorized. Depositing of the concrete shall be so regulated that it may be effectively consolidated in horizontal layers 2.0 feet or less in thickness with a minimum of lateral movement. The amount deposited in each location shall be that which can be readily and thoroughly consolidated. Sufficient placing capacity shall be provided so that concrete placement can be kept plastic and free of cold joints while concrete is being placed. Concrete shall be placed by methods that will prevent segregation or loss of ingredients. Any concrete transferred from one conveying device to another shall be passed through a hopper that is conical in shape. The concrete shall not be dropped vertically more than 5 feet, except where a properly designed and sized elephant truck with rigid drop chute bottom section is provided to prevent segregation and where specifically authorized. In no case will concrete be discharged to free-fall through reinforcing bars.

SECTION 03 31 01.00 10 Page 18

3.2.4 Placement by Pump

When concrete is to be placed by pump, the nominal maximum-size coarse aggregate shall not be reduced to accommodate the pumps. The distance to be pumped shall not exceed limits recommended by the pump manufacturer.

The concrete shall be supplied to the concrete pump continuously. When pumping is completed, concrete remaining in the pipeline shall be ejected without contamination of concrete in place. After each operation, equipment shall be thoroughly cleaned, and flushing water shall be wasted outside of the forms. Grout used to lubricate the pumping equipment at the beginning of the placement will not be incorporated into the placement.

3.2.5 Cold-Weather Placing

When cold-weather placing of concrete is likely to be subjected to freezing temperatures before the expiration of the curing period, concrete shall be placed in accordance with procedures previously submitted. The ambient temperature of the space adjacent to the concrete placement and surfaces to receive concrete shall be above 32 degrees F. The placing temperature of the concrete having a minimum dimension less than 12 inches shall be between 55 and 75 degrees F when measured in accordance with ASTM C1064/C1064M . The placing temperature of the concrete having a minimum dimension greater than 12 inches shall be between 50 and 70 degrees F. Heating of the mixing water or aggregates will be required to regulate the concrete-placing temperatures. Materials entering the mixer shall be free from ice, snow, or frozen lumps. Salt, chemicals, or other materials shall not be mixed with the concrete to prevent freezing.

Submit the proposed materials, methods, and protection for approval, if concrete is to be placed under cold-weather conditions.

3.2.6 Hot-Weather Placing

Concrete shall be properly placed and finished with procedures previously submitted in accordance with paragraph SUBMITTALS. The concrete-placing temperature shall not exceed 90 degrees F when measured in accordance with ASTM C1064/C1064M . Cooling of the mixing water and aggregates, or both, may be required to obtain an adequate placing temperature. A retarder meeting the requirements of paragraph WATER-REDUCING OR RETARDING ADMIXTURES in Part 2 may be used to facilitate placing and finishing.

Steel forms and reinforcement shall be cooled prior to concrete placement when steel temperatures are greater than 120 degrees F. Conveying and placing equipment shall be cooled if necessary to maintain proper concrete-placing temperature.

3.2.7 Consolidation

Immediately after placement, each layer of concrete, including flowing concrete, shall be consolidated by internal vibrating equipment.

Vibrators shall not be used to transport concrete within the forms. Hand spading may be required, if necessary, with internal vibrating along formed surfaces permanently exposed to view. Form or surface vibrators shall not be used unless specifically approved. The vibrator shall be inserted vertically at uniform spacing over the entire area of placement.

The distance between insertions shall be approximately 1-1/2 times the radius of action of the vibrator. The vibrator shall penetrate rapidly to the bottom of the layer and at least 6 inches into the preceding unhardened layer if such exists. It shall be held stationary until the concrete is consolidated and then withdrawn slowly.

SECTION 03 31 01.00 10 Page 19

3.3 FINISHING

The ambient temperature of spaces adjacent to surfaces being finished shall be not less than 40 degrees F. In hot weather when the rate of evaporation of surface moisture, as determined by use of Figure 2.1.5 of ACI 305R , may reasonably be expected to exceed 0.2 pounds per square foot per hour. Make provisions for windbreaks, shading, fog spraying, or wet covering with a light-colored material in advance of placement, and such protective measures shall be taken as quickly as finishing operations will allow. All unformed surfaces that are not to be covered by additional concrete or backfill shall have a float finish. Additional finishing shall be as specified below and shall be true to the elevation shown in the drawings.

Surfaces to receive additional concrete or backfill shall be brought to the elevation shown on the drawings and left true and regular. Exterior surfaces shall be sloped for drainage unless otherwise shown in the drawing or as directed. Joints shall be carefully made with a jointing or edging tool. The finished surfaces shall be protected from stains or abrasions.

Grate tampers or jitterbugs shall not be used.

3.3.1 Unformed Surfaces

3.3.1.1 Float Finish

Surfaces shall be screeded and darbied or bullfloated to bring the surface to the required finish level with no coarse aggregate visible. No water, cement, or mortar shall be added to the surface during the finishing operation. The concrete, while still green but sufficiently hardened to bear a man's weight without deep imprint, shall be floated to a true and even plane. Floating may be performed by use of suitable hand floats or power-driven equipment. Hand floats shall be made of magnesium or aluminum.

3.3.1.2 Trowel Finish

Apply a trowel finish to concrete on the sill. Trowelling shall be done immediately following floating to provide a smooth, even, dense finish free from blemishes including trowel marks. Protect finished surfaces from damage during the construction period.

3.3.2 Formed Surfaces

Unless another finish is specified, surfaces shall be left with the texture imparted by the forms except that defective surfaces shall be repaired as described below.

Uniform color of the concrete shall be maintained by use of only one mixture without changes in materials or proportions for any structure or portion of structure that is exposed to view or on which a special finish is required. Forms shall not be reused if there is any evidence of surface wear or defects that would impair the quality of the surface.

3.3.3 Formed Surface Repair

After removal of forms, all ridges, lips, and bulges on surfaces permanently exposed shall be removed. All repairs shall be completed within 48 hours after form removal.

3.3.3.1 Class A Finishes

Surfaces listed in Section 03 11 14.00 10 FORMWORK FOR CONCRETE and

SECTION 03 31 01.00 10 Page 20 as shown to have class A finish shall have surface defects repaired as follows: defective areas, voids, and honeycombs smaller than 16 square inches in area and less than 1/2 inch deep and bug holes exceeding 1/2 inch in diameter shall be chipped and filled with dry-packed mortar. Holes left by removal of tie rods shall be reamed and filled with dry-packed mortar as specified in paragraph MATERIAL AND PROCEDURE FOR REPAIRS below. Defective and unsound concrete areas larger than described shall be defined by 1/2 inch deep dovetailed saw cuts in a rectangular pattern with lines parallel to the formwork, the defective concrete removed by chipping, and the void repaired with replacement concrete. The prepared area shall be brush-coated with an epoxy resin meeting the requirements of paragraph EPOXY RESIN in PART 2, a latex bonding agent meeting the requirements of paragraph LATEX BONDING COMPOUND in PART 2, or a neat cement grout after dampening the area with water. The void shall be filled with replacement concrete in accordance with paragraph Material And Procedure For Repairs below.

3.3.3.2 Material and Procedure for Repairs

The cement used in the dry-packed mortar or replacement concrete shall be a blend of the cement used for production of project concrete and white portland cement properly proportioned so that the final color of the mortar or concrete will match adjacent concrete. Trial batches shall be used to determine the proportions required to match colors. Dry-packed mortar shall consist of one part cement to two and one-half parts fine aggregate.

The fine aggregate shall be that used for production of project concrete.

The mortar shall be remixed over a period of at least 30 minutes without addition of water until it obtains the stiffest consistency that will permit placing. Mortar shall be thoroughly compacted into the prepared void by tamping, rodding, ramming, etc. and struck off to match adjacent concrete. Replacement concrete shall be produced using project materials and shall be proportioned by the Contracting Officer or their designated representative. It shall be thoroughly compacted into the prepared void by internal vibration, tamping, rodding, ramming, etc. and shall be struck off and finished to match adjacent concrete. Forms shall be used to confine the concrete. If an expanding agent is used in the repair concrete, the repair shall be thoroughly confined on all sides including the top surface. Metal tools shall not be used to finish permanently exposed surfaces. The repaired areas shall be cured for 7 days. The temperature of the in situ concrete, adjacent air, and replacement mortar or concrete shall be above 40 degrees F during placement, finishing, and curing. Other methods and materials for repair may be used only when approved in writing by the Contracting Officer or their designated representative. Repairs of the so called "plaster-type" will not be permitted.

3.4 CURING AND PROTECTION

3.4.1 Duration

The length of the curing period shall be determined by the type of cementitious material, as specified below. Concrete shall be cured by an approved method.

Type I portland cement ------------------------------------- 7 days Portland cement blended with silica fume ------------------- 7 days

Type II portland cement ----------------------------------- 14 days Portland cement blended with 25 percent of less fly-ash --- 14 days

SECTION 03 31 01.00 10 Page 21

Immediately after placement, protect concrete from premature drying, extremes in temperatures, rapid temperature change, and mechanical damage.

All materials and equipment needed for adequate curing and protection shall be available and at the placement site prior to the start of concrete placement. Concrete shall be protected from the damaging effects of rain for 12 hours and from flowing water for 14 days. No fire or excessive heat including welding shall be permitted near or in direct contact with concrete or concrete embedments at any time.

3.4.2 Moist Curing

Moist-cured concrete shall be maintained continuously, not periodically, wet for the entire curing period. If water or curing materials stain or discolor concrete surfaces that are to be permanently exposed, they shall be cleaned as required in paragraph APPEARANCE in PART 1. Where wooden form sheathing is left in place during curing, the sheathing shall be kept wet at all times. If steel forms are used in hot weather, nonsupporting vertical forms shall be carefully broken loose from the concrete, soon after the concrete hardens, and curing water continuously applied into the void so as to continuously saturate the entire concrete surface.

Horizontal surfaces may be moist cured by ponding, by covering with a minimum uniform thickness of 2 inches of continuously saturated sand, or by covering with saturated nonstaining burlap or cotton mats. Horizontal construction joints may be allowed to dry for 12 hours immediately prior to the placing of the following lift. Silica fume concrete, if used, shall be moist-cured. Curing of silica fume concrete shall start immediately after placement.

3.4.3 Cold Weather Curing and Protection

When the daily outdoor low temperature is less than 32 degrees F, the temperature…