A22_amendment_0004.pdf

AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT

Except as provided herein, all terms and conditions of the document referenced in Item 9A or 10A, as heretofore changed, remains unchanged and in full force and effect.

15A. NAME AND TITLE OF SIGNER (Type or print)

30-105-04EXCEPTION TO SF 30

APPROVED BY OIRM 11-84

STANDARD FORM 30 (Rev. 10-83) Prescribed by GSA

FAR (48 CFR) 53.243

Reference Solicitation No. W912EE19B0002 for Delta, Louisiana, River Mile 438.0-R A.H.P., FY-19 Articulated Concrete Mattress Casting, FC/MR&T, Mississippi River, Casting Field. This solicitation is modified as follow s:

See continuation page for changes.

1. CONTRACT ID CODE PAGE OF PAGES

1 2

16A. NAME AND TITLE OF CONTRACTING OFFICER (Type or print)

16C. DATE SIGNED

BY 14-Dec-2018

16B. UNITED STATES OF AMERICA15C. DATE SIGNED15B. CONTRACTOR/OFFEROR

(Signature of Contracting Officer)(Signature of person authorized to sign)

8. NAME AND ADDRESS OF CONTRACTOR (No., Street , County, State and Zip Code) X W912EE19B0002

X 9B. DATED (SEE ITEM 11)

15-Nov-2018

10B. DATED (SEE ITEM 13)

9A. AMENDMENT OF SOLICITATION NO.

11. THIS ITEM ONLY APPLIES TO AMENDMENTS OF SOLICITATIONS

X The above numbered solicitation is amended as set forth in Item 14. The hour and date specified for receipt of Offer is extended, X is not extended.

Offer must acknowledge receipt of this amendment prior to the hour and date specified in the solicitation or as amended by one of the following methods:

(a) By completing Items 8 and 15, and returning copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted;

or (c) By separate letter or telegram which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGMENT TO BE RECEIVED AT THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN

REJECTION OF YOUR OFFER. If by virtue of this amendment you desire to change an offer already submitted, such change may be made by telegram or letter, provided each telegram or letter makes reference to the solicitation and this amendment, and is received prior to the opening hour and date specified.

12. ACCOUNTING AND APPROPRIATION DATA (If required)

13. THIS ITEM APPLIES ONLY TO MODIFICATIONS OF CONTRACTS/ORDERS.

IT MODIFIES THE CONTRACT/ORDER NO. AS DESCRIBED IN ITEM 14.

A. THIS CHANGE ORDER IS ISSUED PURSUANT TO: (Specify authority) THE CHANGES SET FORTH IN ITEM 14 ARE MADE IN THE

CONTRACT ORDER NO. IN ITEM 10A.

B. THE ABOVE NUMBERED CONTRACT/ORDER IS MODIFIED TO REFLECT THE ADMINISTRATIVE CHANGES (such as changes in paying office, appropriation date, etc.) SET FORTH IN ITEM 14, PURSUANT TO THE AUTHORITY OF FAR 43.103(B).

C. THIS SUPPLEMENTAL AGREEMENT IS ENTERED INTO PURSUANT TO AUTHORITY OF:

D. OTHER (Specify type of modification and authority)

E. IMPORTANT: Contractor is not, is required to sign this document and return copies to the issuing office.

14. DESCRIPTION OF AMENDMENT/MODIFICATION (Organized by UCF section headings, including solicitation/contract subject matter where feasible.)

10A. MOD. OF CONTRACT/ORDER NO.

2. AMENDMENT/MODIFICATION NO. 5. PROJECT NO.(If applicable)

6. ISSUED BY

3. EFFECTIVE DATE

14-Dec-2018

CODE

VICKSBURG CONTRACTING OFFICE

4155 CLAY ST

VICKSBURG MS 39183-3435

W912EE 7. ADMINISTERED BY (If other than item 6)

4. REQUISITION/PURCHASE REQ. NO.

CODE

See Item 6

FACILITY CODECODE

EMAIL:TEL:

W912EE19B0002

SECTION SF 30 BLOCK 14 CONTINUATION PAGE

SUMMARY OF CHANGES

SECTION SF 30 - BLOCK 14 CONTINUATION PAGE

The following have been added by full text:

SPECIFICATIONS: Section C – 00 09 00 and Section F are revised and replaced.

Specifications revised by this amendment have the notation "Revised by Amendment 0004" at the bottom of the page. Text added by this amendment is shown as underlined. Text deleted by this amendment is shown as overstruck.

(End of Summary of Changes)

W912EE-19-B-0002

SECTION TABLE OF CONTENTS

DIVISION 00 - PROCUREMENT AND CONTRACTING REQUIREMENTS

SECTION C

DESCRIPTION/SPECIFICATIONS

1 DESCRIPTION OF WORK

1.1 SCOPE

1.1.1 Definition of a "Square"

1.1.2 Location

1.2 PHYSICAL DATA

1.2.1 Access Roads

1.2.2 Railroads

1.2.3 Rivers

1.2.4 Electricity

1.2.5 Water

1.3 OTHER WORK

1.4 CONTRACT DRAWINGS AND SPECIFICATIONS

1.5 FIELD LAYOUT

1.6 APPLICABLE PUBLICATIONS

2 MATERIALS

2.1 CEMENTITIOUS MATERIALS

2.1.1 Portland Cement

2.1.2 Fly Ash

2.1.3 Transportation of Bulk Cement and Fly Ash

2.1.4 Storage

2.1.5 Quality Control and Quality Assurance

2.2 CALCIUM CHLORIDE

2.2.1 Quality Control and Quality Assurance

2.3 AIR-ENTRAINING ADMIXTURE

2.3.1 Quality Control and Quality Assurance

2.4 WATER-REDUCING ADMIXTURE

2.4.1 Quality Control and Quality Assurance

2.5 AGGREGATE

2.5.1 Composition

2.5.2 Quality

2.5.3 Quality Control and Quality Assurance

2.5.4 Fine Aggregate

2.5.4.1 Storage of Fine Aggregate

2.5.5 Coarse Aggregate

2.5.5.1 Storage of Coarse Aggregates

2.6 WATER

2.7 CURING COMPOUNDS

2.7.1 Quality Control and Quality Assurance

2.8 KRAFT PAPER

2.8.1 Quality Control and Quality Assurance

3 PLANT REQUIREMENTS

DOCUMENT 00 90 00 Page 1 Reveised By Amendment 0004

3.1 MEASUREMENT

3.2 WEIGHT BATCHERS

3.3 SCALES

3.4 INTERLOCKS

3.5 MOISTURE CONTROL METER

3.6 RECORDER

3.7 BATCH COUNTERS

3.8 ADMIXTURE DISPENSERS

3.9 SAMPLING

3.10 CONTROL EQUIPMENT PROTECTION

3.11 CONCRETE MIXERS

3.11.1 General

3.11.2 Stationary Mixers

3.11.3 Truck Mixers

3.11.4 Paving Mixers

3.12 ARTICULATED CONCRETE MATTRESS

3.12.1 Scope

3.12.2 Composition

3.12.2.1 Concrete

3.12.3 Proportioning of Concrete

3.12.3.1 General

3.12.3.2 Water Content

3.12.3.3 Cementitious Materials Content

3.12.3.4 Aggregate Content

3.12.3.5 Placability

3.12.3.6 Slump

3.12.3.7 Air-Entraining

3.12.3.8 Calcium Chloride

3.13 CONCRETE CONVEYING

3.14 TRIAL OPERATION

3.15 CASTING

3.15.1 General

3.15.2 Casting Procedure

3.15.2.1 Paper Installation

3.15.2.2 Form Placement

3.15.2.3 Form Release Agent - Other Than Commercial Products

3.15.2.3.1 General

3.15.2.3.2 Acceptance Criteria

3.15.2.3.3 Sampling

3.15.2.3.4 Analysis

3.15.2.3.5 Analytical Requirements

3.15.2.4 Form Release Agent - Usage

3.15.2.5 Form Release Agent - Disposal Prohibition

3.15.2.6 Concrete Placement

3.15.2.7 Roughened Finish

3.15.2.8 Form Stripping

3.15.2.9 Form Cleanup and Form Straightening

3.15.2.10 Marking Mat

3.16 CURING AND PROTECTION

3.16.1 Warm Weather

3.16.1.1 Curing Compound

3.16.2 Cold Weather

3.16.3 Rainy Weather

3.17 EXCESS PAPER

3.18 REPLACING DEFICIENT MATTRESS

3.19 REPAIR OF DEFICIENT MATTRESS AFTER FORM STRIPPING

3.20 FIELD CONDITIONS

3.20.1 Field Maintenance

3.20.2 Wet Field Conditions

DOCUMENT 00 90 00 Page 2

3.20.3 Casting Field Flooding

3.21 RECORDS

3.22 MEASUREMENT AND PAYMENT

3.22.1 General

3.22.2 Articulated Concrete Mattress

3.22.3 Cement

3.22.4 Fly Ash

3.22.5 Corner Reinforcement

3.23 PARTIAL PAYMENTS

-- End of Section Table of Contents --

DOCUMENT 00 90 00 Page 3

SECTION C

DESCRIPTION/SPECIFICATIONS

C- 1 DESCRIPTION OF WORK

C- 1.1 SCOPE

The work to be performed under this contract consists of furnishing all plant, materials (except materials specified herein to be furnished by the Government), equipment, supplies, labor, transportation, fuel, power and water, and performing all work as required in casting squares of articulated concrete mattress at Delta, LA and in the quantity shown on the bidding schedule, in strict accordance with the specifications, schedules and drawings, all of which are made a part thereof, and including such detail drawings as may be furnished by the Contracting Officer during the prosecution of the work.

Under the Comprehensive Procurement Guidelines (CPG) program, the Environmental Protection Agency (EPA) designates products that are or can be made with recovered materials, and recommends practices for buying these products. Any designated product that is being offered or supplied under this contract shall meet the minimum recommended content levels as identified under the CPG program. Visit http://www.epa.gov/epawaste/conserve/tools/cpg/products for a complete list of designated products and the associated recommended content levels.

Offerors must be able to demonstrate that each offered product meets minimum content levels upon request.

C- 1.1.1 Definition of a "Square"

The definition of a "square" of articulated concrete mattress as referred to in these specifications consists of one section, approximately 25 feet x 4 feet x 3 inch, containing 16 blocks, cast on a single unit of fabric.

C- 1.1.2 Location

The casting field is located along the right descending bank of the Mississippi River near Delta, Louisiana.

C- 1.2 PHYSICAL DATA

C- 1.2.1 Access Roads

A gravel road leads to the casting field. The use of the roads along the top of the levee is regulated by the Fifth Louisiana Levee District.

Authority for such use must be obtained by the Contractor in advance from the Fifth Louisiana Levee District. It shall be the Contractor's responsibility to make any necessary arrangements to provide access for plant, labor, materials and equipment, both to and from the Delta Casting Field.

C- 1.2.2 Railroads

There is a railroad siding, if needed, in Delta, Louisiana. The Contractor is responsible for determining the availability of railroad service.

DOCUMENT 00 90 00 Page 4

C- 1.2.3 Rivers

The casting field is accessible via the Mississippi River.

C- 1.2.4 Electricity

Electric power service is located at the casting field, and electricity may be procured commercially at the Contractor's expense. The Contractor shall make his own arrangements for power, including terminating utilities.

C- 1.2.5 Water

Water may be procured commercially at the Contractor's expense, or it may be obtained from the Mississippi River provided it meets the requirements for water as set out in these specifications. The Contractor shall make his own arrangements for water, supply and termination of utilities.

C- 1.3 OTHER WORK

The Government may desire to load completed mattress sections or perform other work on the Government premises or in the immediate vicinity either by Government personnel or contract while the Contractor's casting operations are in progress. The Contractor's plant layout or order of work shall be such as to avoid interference with the loading operations, storage and transportation of materials, storage of existing mattress, casting of additional mattress, or other work not included in this contract.

C- 1.4 CONTRACT DRAWINGS AND SPECIFICATIONS

(a) The Government will provide to the Contractor, without charge, one set of contract drawings and specifications, except publications incorporated into the technical provisions by reference, in electronic or paper media as chosen by the Contracting Officer.

(b) The Contractor shall --

(1) Check all drawings furnished immediately upon receipt;

(2) Compare all drawings and verify the figures before laying out the work;

(3) Promptly notify the Contracting Officer of any discrepancies;

(4) Be responsible for any errors which might have been avoided by complying with this paragraph (b); and

(5) Reproduce and print contract drawings and specifications as needed.

(c) In general --

(1) The Contractor shall follow figures marked on drawings in preference to scale measurements.

(d) Omissions from the drawings or specifications or the misdescription of details of work which are manifestly necessary to carry out the intent of the drawings and specifications, or that are customarily performed, shall not relieve the Contractor from performing

DOCUMENT 00 90 00 Page 5 such omitted or misdescribed details of the work. The Contractor shall perform such details as if fully and correctly set forth and described in the drawings and specifications.

(e) The work shall conform to the specifications and the contract drawings identified on the following index of drawings:

Drawing No. Title

G-001 COVER SHEET

G-002 GENERAL MAP

C-101 FIELD LAYOUT

C-102 TYPICAL LAYOUT AND STANDARD DETAILS

C-501 TYPICAL ONE PIECE STEEL FORM

X-101 STORM WATER POLLUTION PREVENTION PLAN

(DFARS 252.236-7001)

C- 1.5 FIELD LAYOUT

The initial casting field layout shall be as shown on Drawing No. C-101, FIELD LAYOUT. After work is underway, the casting field layout and/or order of work may be altered to avoid hampering or being hampered by mat loading operation. Mattress stacks and rows of standard mattress shall be developed from these layouts in a manner similar to that shown on Drawing No. C-102, TYPICAL LAYOUT AND STANDARD DETAILS.

C- 1.6 APPLICABLE PUBLICATIONS

The following publications of the issues listed below, but referred to thereafter by basic designation only, form a part of this specification to the extent indicated by the references thereto:

ASTM INTERNATIONAL (ASTM)

ASTM C33/C33M (2013) Standard Specification for Concrete Aggregates

ASTM C94/C94M (2015) Standard Specification for Ready-Mixed Concrete

ASTM C 123 (2004) Standard Test Method for Lightweight Particles in Aggregate

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

ASTM C150/C150M (2015) Standard Specification for Portland Cement

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

ASTM C231/C231M (2014) Standard Test Method for Air

DOCUMENT 00 90 00 Page 6

Content of Freshly Mixed Concrete by the Pressure Method

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

ASTM C494/C494M (2015a) Standard Specification for Chemical Admixtures for Concrete

ASTM C595/C595M (2015; E 2015) Standard Specification for Blended Hydraulic Cements

ASTM C618 (2012a) Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete

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

ASTM D98 (2015) Calcium Chloride

ASTM D4791 (2010) Flat Particles, Elongated Particles, or Flat and Elongated Particles in Coarse Aggregate

U.S. GENERAL SERVICES ADMINISTRATION (GSA)

CID A-A-203 (Rev C; Notice 3) Paper, Kraft, Untreated

U.S. NATIONAL ARCHIVES AND RECORDS ADMINISTRATION (NARA)

40 CFR 279 Standards for the Management of Used Oil

U.S. ARMY CORPS OF ENGINEERS (USACE)

COE CRD-C 55 (1992) Test Method for Within-Batch Uniformity of Freshly Mixed Concrete

COE CRD-C 143 (1962) Specifications for Meters for Automatic Indication of Moisture in Fine Aggregate

COE CRD-C 300 (1990) Specifications for Membrane-Forming Compounds for Curing Concrete

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

NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY (NIST)

NIST HB 44 (2013) Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices

C- 2 MATERIALS

C- 2.1 CEMENTITIOUS MATERIALS

DOCUMENT 00 90 00 Page 7

C-2.1.1 Portland Cement

Portland Cement shall conform to ASTM C150/C150M, Type I, including false set requirements, except that the maximum amount of C 3A shall be 15 percent.

C- 2.1.2 Fly Ash

Fly ash shall conform to ASTM C618, Class C or F, including the maximum alkalies, uniformity and multiple factor requirements. The loss on ignition for fly ash shall be limited to a maximum of 6 percent.

C- 2.1.3 Transportation of Bulk Cement and Fly Ash

When bulk cement and/or fly ash is not unloaded from primary carriers directly into weathertight hoppers at the batching plant, transportation from the railhead, mill, or intermediate storage area to the batching plant shall be accomplished in weathertight trucks, conveyors, or other means which will protect the cement and fly ash completely from exposure to moisture.

C- 2.1.4 Storage

Separate storage facilities shall be provided for cement and fly ash. The cement and fly ash tanks shall be clearly labled with 12 inch letters (minimum). Immediately upon receipt at the site of the work, cement and fly ash shall be stored in a dry weathertight and properly ventilated structure with adequate provisions for the prevention of absorption of moisture. Charging valves for storage of cement and fly ash shall be clearly marked to prevent inadvertent loading of the wrong material into this structure. All storage facilities shall be subject to approval and shall permit easy access for inspection and identification. In order that cement and fly ash not become unduly aged after delivery, the Contractor shall use any cement or fly ash which has been stored at the site for 60 days or more before using cement or fly ash of lesser age. Fly ash or cement obtained from different sources shall not be stored in the same storage bin. The temperature of the cement and fly ash, as delivered to the site, shall not exceed 150 degrees F.

C- 2.1.5 Quality Control and Quality Assurance

The Contractor shall notify the Contracting Officer of the source from which the cement and fly ash will be obtained within 10 days after award of the contract. Cement and fly ash will be accepted on the basis of a manufacturer's mill certificate of compliance. Unless otherwise authorized, no cement or fly ash shall be used until a satisfactory manufacturer's mill certificate for that cement or fly ash is in the possession of the Contracting Officer at the site of the work and same has been accepted. If the manufacturer's certificate indicates that the cement or fly ash which has been delivered is unsatisfactory, it shall be promptly removed from the site of the work by and at the expense of the Contractor.

Fly ash and cement samples will be tested periodically during the casting season, at the Governments's expense, to check compliance with the specifications. Cement and/or fly ash which has not been used within 4 months after testing shall be retested at the expense of the Contractor when directed by the Contracting Officer and will be rejected if test results are not satisfactory.

DOCUMENT 00 90 00 Page 8

C-2.2 CALCIUM CHLORIDE

Calcium chloride shall meet the requirements of ASTM D98, Type S, Grade 1, 2 or 3.

C- 2.2.1 Quality Control and Quality Assurance

Calcium chloride will be accepted on the basis of a manufacturer's mill certificate or certificate of compliance, furnished in duplicate, to the Contracting Officer at the time of delivery.

C- 2.3 AIR-ENTRAINING ADMIXTURE

The air-entraining admixture shall conform to ASTM C260/C260M and shall consistently entrain the air content in the specified ranges under field conditions. The air-entraining admixture shall be in a solution of suitable viscosity for field use requiring no further dilution.

C- 2.3.1 Quality Control and Quality Assurance

The Contractor shall notify the Contracting Officer of the source from which the admixture will be obtained within 10 days after award of contract. The admixture will be accepted on the basis of mill certificates or certificates of compliance which certify that the admixture meets the specified requirements. The admixture may be tested periodically, at the expense of the Government, to check compliance with the specifications.

The Contractor shall provide satisfactory facilities for the procurement of test samples by the Contracting Officer. An air entraining admixture which has been in storage at the project site for longer than 6 months or which has been subjected to freezing shall be retested at the expense of the Contractor when directed by the Contracting Officer and shall be rejected if test results are not satisfactory.

C- 2.4 WATER-REDUCING ADMIXTURE

The water-reducing admixture shall conform to the requirements of ASTM C494/C494M, Type A. The purpose of the admixture is to reduce the quantity of water otherwise required in a similar mixture without this admixture to produce concrete of a given consistency and reduce the cement required by approximately 10 percent of the quantity which would be required without this admixture.

C- 2.4.1 Quality Control and Quality Assurance

The Contractor shall notify the Contracting Officer of the source from which the admixture will be obtained within 10 days after award of the contract. The admixture will be accepted on the basis of mill certificates or certificates of compliance which certify that the admixture meets the specified requirements. At the discretion of the Contracting Officer, the admixture may be tested periodically, at the expense of the Government, to check compliance with the specifications. The Contractor shall provide satisfactory facilities for the procurement of test samples by the Contracting Officer. A water-reducing admixture which has been in storage at the project site for longer than 6 months or which has been subjected to freezing shall be retested at the expense of the Contractor prior to its use.

DOCUMENT 00 90 00 Page 9

C-2.5 AGGREGATE

C- 2.5.1 Composition

Fine aggregate shall consist of natural sand, or a combination of natural and manufactured sands. Coarse aggregate shall consist of gravel, crushed gravel, crushed stone, or a combination thereof.

C- 2.5.2 Quality

Aggregate, as delivered to the mixer, shall consist of clean, hard, and uncoated particles. Where required, fines shall be removed from the course aggregates by adequate washing, or another suitable method approved by the Contracting Officer. The quantity of flat and/or elongated particles in the separated size groups of coarse aggregates, as defined and determined by ASTM D4791, shall not exceed 25 percent. The quality of the aggregates shall conform to ASTM C33/C33M, Class 4M.

C- 2.5.3 Quality Control and Quality Assurance

The Contractor shall notify the Contracting Officer of the sources from which the aggregates will be obtained within 10 days after award of contract. The aggregates will be accepted on the basis of certificates of compliance which certify that the aggregates meet the specified requirements. During construction, aggregate will be sampled in accordance with ASTM D75/D75M, as delivered to the mixer, to determine compliance with the specifications. The Contractor shall provide facilities and labor as may be necessary for the ready procurement of representative test samples.

Samples from the weigh batcher shall be obtained when directed by the Contracting Officer and under his supervision. The Government will test such samples at its expense using appropriate Corps of Engineers' and ASTM testing methods. Tests of aggregates at various stages in the casting process and handling operations will be made at the discretion of the Contracting Officer.

C- 2.5.4 Fine Aggregate

Fine aggregate shall be graded from fine to coarse and the gradation shall be within the following limits as delivered to the mixer or as incorporated in the mixed concrete:

Sieve Size Percent Passing

3/8 inch 100 No. 4 95 - 100 No. 16 4550 - 9094 No. 50 75 - 30 No. 100 0 - 710 No. 200 0 - 3

C- 2.5.4.1 Storage of Fine Aggregate

Fine aggregate shall be stored in such a manner as to avoid the inclusion of any foreign materials. The storage piles shall be constructed so as to prevent segregation. The storage of the material in storage piles and its removal therefrom shall be accomplished in such a manner as to result in maintaining uniformity of gradation. All fine aggregate shall remain in the stockpile for at least 96 hours prior to use. Sufficient aggregate shall be maintained at the site at all times to permit continuous placement

DOCUMENT 00 90 00 Page 10 of concrete at the specified rate. Any unacceptable material that is introduced to the stockpile shall be promptly separated from previously accepted material and removed from the stockpiled area before continuation of casting or within 24 hours if occurring during a period of no casting.

C- 2.5.5 Coarse Aggregate

Coarse aggregate shall conform to the following gradation requirements as delivered to the mixer or as incorporated in the mixed concrete:

Sieve Size Percent Passing

1-1/2 inch 100 1 inch 90 - 100 1/2 inch 25 - 60 No. 4 0 - 10 No. 8 0 - 5 No. 200 0 - 1

C- 2.5.5.1 Storage of Coarse Aggregates

Coarse aggregate storage piles shall be built adjacent to the batch plant and in such manner as to avoid the inclusion of any foreign material.

Coarse aggregate shall remain in the stockpile for at least 48 hours prior to use. The storage piles shall be constructed so as to prevent segregation and to provide for drainage away from the storage piles. The disposition of the material in storage and its removal therefrom shall be accomplished in such a manner as to result in maintaining the uniformity of the gradation. Sufficient aggregate shall be maintained at the site at all times to permit continuous placement of concrete at the specified rate.

Any unacceptable material that is introduced to the stockpile shall be promptly separated from previously accepted material and removed from the stockpiled area before continuation of casting or within 24 hours if occurring during a period of no casting.

C- 2.6 WATER

Water for mixing shall be clean and potable, except that nonpotable water may be used if it meets the requirements of COE CRD-C 400 . Water for curing shall not contain any substance that is injurious to the concrete.

C- 2.7 CURING COMPOUNDS

Curing compounds shall be of the surface membrane type, shall be pigmented, and shall comply with the requirements of COE CRD-C 300 .

C- 2.7.1 Quality Control and Quality Assurance

The Contractor shall furnish certificates of compliance, at or before the time of delivery, in duplicate, to the Contracting Officer which certify that the curing compound meets the specified requirements.

C- 2.8 KRAFT PAPER

The paper used as separators between mattress squares shall be not less than 48 inches and not greater than 50 inches in width, and shall conform to the maximum requirements set out in CID A-A-203 (Rev C), Style 1, with the exception of the requirements specified herein. The paper basis weight shall be not less than 99 pounds; that is, 500 sheets, 24 by 36 inches

DOCUMENT 00 90 00 Page 11 shall weigh not less than 99 pounds. The Contractor may, at his option and at no additional cost to the Government, elect to use a heavier weight paper that meets or exceeds the requirements of the Commercial Item Description.

C- 2.8.1 Quality Control and Quality Assurance

The Contractor shall either furnish mill certificates or certificates of compliance, in duplicate, to the Contracting Officer which certify that the paper meets the specified requirements.

C- 3 PLANT REQUIREMENTS

C- 3.1 MEASUREMENT

All materials entering into the concrete shall be mechanically batched and measured by weight, except that the admixtures may be batched by volume, and water may be batched by weight or volume. One gallon of water will be considered as 8.33 pounds in weight.

C- 3.2 WEIGHT BATCHERS

The weight batchers shall be arranged to permit the convenient addition or removal of material. The weight batchers shall be so constructed and arranged that the sequence and timing of batcher discharge gates can be controlled to produce a ribboning and mixing of the aggregates, water, and of the cement and fly ash with aggregates as the materials pass through the charging hopper into the mixer. The plant shall include provisions to facilitate the inspection of all operations at all times. Delivery of materials from the batching equipment shall be within the following limits of accuracy:

Material Percent

Cement and Fly Ash plus or minus 1 Water plus or minus 1 Aggregate plus or minus 2 Admixtures plus or minus 3

C- 3.3 SCALES

The batch plant shall include adequate facilities for the accurate measurement and control of each of the materials entering each batch of concrete. The accuracy of weighing equipment shall conform to the applicable requirements of NIST HB 44 , except that the accuracy shall be within 0.2 percent of scale capacity. The Contractor shall provide standard test weights and any other auxiliary equipment required for checking the operating performance of each scale or other measuring device.

Periodic tests shall be made in the presence of a Contracting Officer in such a manner and at such intervals as may be directed. Upon completion of each check test and before further use of the indicating, recording, or control devices, the Contractor shall make such adjustments, repairs or replacement as may be required for satisfactory performance. Each weighing unit shall include a visible springless dial or electronic indicator which shall indicate the scale load at all stages of the weighing operation or shall include a beam scale with a beam balance indicator which will show the scale in balance at zero load at any beam setting. The indicator shall have an over and under travel equal to at least 5 percent of the capacity of the beam. The weighing equipment shall be arranged so that the concrete

DOCUMENT 00 90 00 Page 12 plant operator can conveniently observe the dials or indicators.

C- 3.4 INTERLOCKS

Batchers and mixers shall be interlocked so that:

(1) The charging mechanism of each batcher cannot be opened until the scale has returned to zero,

(2) The charging mechanism cannot be opened if the discharge mechanism is opened,

(3) The discharge mechanism cannot be opened if the charging mechanism is open,

(4) The discharge mechanism cannot be opened until the designated weight has been reached within the allowable tolerance,

(5) One admixture is batched automatically with the water,

(6) Each additional admixture is batched automatically with a separate portion of the water or with the fine aggregate, and

(7) The mixers cannot be discharged until the required mixing time has elapsed.

C- 3.5 MOISTURE CONTROL METER

The plant shall be capable of ready adjustment to compensate for the varying moisture content of the aggregate in order to change the weights of the materials being batched. An electric moisture meter complying with the provisions of COE CRD-C 143 shall be provided for measurement of moisture in the fine aggregate. The sensing element shall be arranged so that the measurement is made near the batcher charging gate of the sand bin or in the sand batcher.

C- 3.6 RECORDER

An accurate recorder shall be provided and shall conform to the following requirements:

(1) The recording units shall be completely housed in a single cabinet which shall be capable of being locked.

(2) The recorder shall produce a graphical or digital record on a single visible chart or tape which shall indicate the weight or volume of each material in the batchers at the conclusion of the batching cycle. The record shall be produced prior to the delivery of the materials to the mixer. After the batchers have been discharged, the recorder shall indicate the return of the batcher to the empty condition.

(3) The chart or tape shall be so marked that each batch may be permanently identified and so that variations in batch weights of each type of batch can be readily observed.

(4) The chart or tape shall show the date and time of day at intervals of not more than 15 minutes. Gradation lines on the cementitious materials chart shall be at intervals of not more than 20 pounds.

DOCUMENT 00 90 00 Page 13

(5) The recorded chart or tape shall become the property of the Government.

(6) The recorder shall be placed in a position convenient for observation by the concrete plant operator and the Contracting Officer, and mounted to prevent excessive vibration which causes inaccurate readings.

(7) The recorded weights or volumes, when compared to the weights or volumes actually batched, shall be within 12 percent.

C- 3.7 BATCH COUNTERS

The plant shall include devices for automatically counting the total number of batches of all concrete batched.

C- 3.8 ADMIXTURE DISPENSERS

An accurate mechanical system for measuring and dispensing each admixture shall be provided. Each system shall be capable of ready adjustment to permit varying the quantity of admixtures to be batched. Each admixture shall be added to the batch in a separate portion of the mixing water or in a separate portion of the fine aggregate in a manner to ensure uniform distribution of the admixtures throughout the batch. The dispensing systems shall provide a convenient means of visually observing from the control panel the admixture in process of being batched or discharged.

C- 3.9 SAMPLING

The Contractor shall provide suitable facilities and labor for obtaining representative samples of concrete from the mixer or the wet batch hopper for Contractor quality control and Government quality assurance testing.

All necessary platforms, tools, and equipment for obtaining samples shall be furnished by the Contractor.

C- 3.10 CONTROL EQUIPMENT PROTECTION

The indicating, recording, and control equipment shall be sufficiently protected against exposure to dust, moisture and vibration so there will be no interference with proper operation of the equipment.

C- 3.11 CONCRETE MIXERS

C- 3.11.1 General

Mixers may be stationary mixers, truck mixers, paving mixers, or turbine-type mixers of approved design. The mixers shall have a rated capacity of at least 27 cubic feet of mixed concrete and shall not be charged in excess of the capacity recommended by the manufacturer. Mixers shall be capable of combining the materials into a uniform mixture and of discharging this mixture without segregation. Each stationary and paving mixer shall be provided with an acceptable device to lock the discharge mechanism until the required mixing time has elapsed. Truck mixers shall be equipped with accurate revolution counters. The mixers shall be operated at the drum or blade speed designated by the manufacturer on the nameplate. The acceptability of truck mixers will be determined by uniformity tests as required by ASTM C94/C94M. The mixing periods specified herein are predicated on proper control of the speed of rotation

DOCUMENT 00 90 00 Page 14 of the mixer drum or mixing blades and on proper introduction of the materials into the mixer. The mixing time of stationary or paving mixtures shall be increased when such increase is necessary to secure the required uniformity of the concrete or when test samples of concrete taken from the first, middle and last portions of the mixer discharge is less than any of the following requirements when tested in accordance with the provisions of COE CRD-C 55 . When authorized by the Contracting Officer, the mixing time may be reduced to the minimum time required to meet all the following requirements.

Maximum Allowable Variation of Any One Test Value from the Test Average of Three

Weight per cubic foot of mortars calculated to an air-free basis, lb/ft3 plus or minus 1.6

Air content, volume percent of plus or minus 1.0 concrete

Slump, inches plus or minus 1.0

Coarse aggregate content, portion by weight of each sample retained on No. 4 sieve, percent plus or minus 6.0

Average compressive strength at 7 days, percent plus or minus 10.0

Water content, portion by weight of each sample passing No. 4 sieve, percent plus or minus 1.5

When the Contractor proposes to reduce the mixing time, uniformity tests at reduced mixing time will be made by the Government, at the Contractor's expense, to determine whether the reduced mixing time meets the requirements of the specifications. Excessive over-mixing requiring additions of water will not be permitted. The mixers shall be maintained in satisfactory operating condition, and mixer drums shall be kept free of hardened concrete. Mixer blades shall be replaced when worn more than 10 percent of their initial depth. Should any mixer at any time produce unsatisfactory results, its use shall be promptly discontinued until it is repaired. Suitable facilities shall be provided for obtaining representative samples of concrete for uniformity tests. All necessary platforms, tools, labor and equipment for obtaining samples shall be furnished by the Contractor.

C- 3.11.2 Stationary Mixers

If no uniformity test data are available, the mixing time for each batch after all solid materials are in the mixer shall be one minute for mixers having a capacity of one cubic yard, provided that all of the mixing water is introduced before one-fourth of the mixing time has elapsed. For mixers of larger capacities, the minimum mixing time shall be increased 15 seconds for each additional cubic yard or fraction thereof of concrete mixed. When a stationary mixer is used for partial mixing of the concrete (shrink-mixing), the mixing time in the stationary mixer may be reduced to

DOCUMENT 00 90 00 Page 15 the minimum necessary to intermingle the ingredients (about 30 seconds).

C- 3.11.3 Truck Mixers

Truck mixers and the mixing of concrete therein 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 accomplished in a stationary mixer (shrink-mixed). Each truck shall be equipped with two counters from which can be determined the number of revolutions at mixing speed and the number of revolutions at agitating speed.

C- 3.11.4 Paving Mixers

Paving mixers, if used, shall be used at the site of the work. Paving mixers may be either single compartment drum or multiple compartment drum type. Multiple compartment drum paving mixers shall be properly synchronized and the mixing time shall be determined by including the time required to transfer the concrete between compartments of the drum. If no uniformity test data are available, the mixing time for each batch (after all solid materials are in the mixer drum) shall be one minute for mixers having a capacity of one cubic yard, provided that all the mixing water is introduced before one-fourth of the mixing time has elapsed. For mixers of larger capacities, the minimum mixing time shall be increased 15 seconds for each additional cubic yard or fraction thereof of concrete mixed.

Vehicles used in transporting material from the batching plant to the mixers shall have bodies or compartments of adequate capacity to carry the materials and to deliver each batch, separate and intact, to the mixer.

Except as otherwise approved by the Contracting Officer, loose cement and fly ash shall be transported from the batching plant to the mixers in separate boxes or compartments which shall be equipped with windproof and rainproof covers.

C- 3.12 ARTICULATED CONCRETE MATTRESS

C- 3.12.1 Scope

The work covered by this section consists of furnishing all materials and equipment except as provided in Section H - SPECIAL CONTRACT REQUIREMENTS, paragraph GOVERNMENT-FURNISHED FACILITIES and paragraph IDENTIFICATION OF GOVERNMENT-FURNISHED PROPERTY, and performing all labor for the manufacturing, transporting, placing, finishing, and curing of concrete in the articulated concrete mattress.

C- 3.12.2 Composition

C- 3.12.2.1 Concrete

Concrete for articulated mattress shall be composed of cementitious materials, water, fine and coarse aggregate, air-entraining and water-reducing admixtures, and at the option of the Contractor, an accelerating admixture (calcium chloride).

C- 3.12.3 Proportioning of Concrete

C- 3.12.3.1 General

The proportion of all material entering into the concrete shall be as directed by the Contracting Officer. The Contractor shall provide all

DOCUMENT 00 90 00 Page 16 necessary equipment and plant to determine and control the actual quantities of material entering each batch. The proportions will be changed by the Contracting Officer whenever such change is necessary in order to maintain the standard of quality required.

C- 3.12.3.2 Water Content

The water content of all concrete mixtures shall not be more than 68 pounds per hundredweight of cementitious materials.

C- 3.12.3.3 Cementitious Materials Content

The cementitious materials content of the concrete shall range from an approximate minimum of 2.1 to an approximate maximum of 4.0 hundredweights per cubic yard, depending on size, type, and gradation of aggregate used, and on the structural requirements as determined by the Contacting Officer.

The cementitious material shall consist of a blend ranging from 65 percent Portland cement and 35 percent fly ash to 75 percent Portland cement and 25 percent fly ash by absolute volume of the total. The Contractor may adjust the mix by substituting Portland cement for fly ash in order to accelerate set time. Additional costs resulting from such adjustment shall be at no additional expense to the Government. The Government reserves the right to change the mix design by directing substitution of cement for fly ash.

When so directed, payment for theoretical batch weights of cement and fly ash in the new mix will be made at the applicable contract unit price.

C- 3.12.3.4 Aggregate Content

Concrete mixes will be designed to use the maximum quantity of coarse aggregate placeable in the various parts of the form and the aggregate plant shall be designed on this basis.

C- 3.12.3.5 Placability

The concrete mixtures which have been designed and tested in the laboratory will be adjusted in the field from time to time to meet the varying conditions encountered during casting operations. The water content of all concrete mixtures will be the minimum necessary to properly place the mixture being used.

C- 3.12.3.6 Slump

The slump will be stipulated by the Contracting Officer and shall be three inches plus or minus one inch as determined by ASTM C143/C143M. Concrete sampling shall be done in accordance with ASTM C172.

C- 3.12.3.7 Air-Entraining

An air-entraining admixture shall be added at the mixer to each batch of concrete. The quantity of admixture used shall be such as to control the quantity of entrained air within the concrete to within the limits of 4 to 7 percent as determined by ASTM C231/C231M when the concrete is discharged from the mixer. The intent is to maintain the entrained air in the concrete as near as practicable to 5.5 percent while allowing some latitude for individual batches. Concrete sampling shall be done in accordance with

ASTM C172.

DOCUMENT 00 90 00 Page 17

C-3.12.3.8 Calcium Chloride

At the Contractor's option and expense, a solution not exceeding 2 pounds of crystal or pellet calcium chloride per hundredweight of cement may be used in the concrete mixture. The calcium chloride shall be dissolved in water in the ratio of 1 pound of crystals or pellets to 2 pounds of water and the mixing solution used to replace a similar quantity of the mixing water. Should a calcium chloride solution be used, none of the other conditions of the specifications applying to mixing, placing, or curing the concrete will be waived. To facilitate the maintenance of a workable mixture and good project records, the Contractor shall, at the start of casting operations each day, inform the Contracting Officer as to the quantity of calcium chloride to be used. He shall continue such notification approximately 20 minutes in advance of each change in quantity of calcium chloride throughout the day.

C- 3.13 CONCRETE CONVEYING

Concrete shall be conveyed from mixer to forms as rapidly as practicable by methods which will prevent segregation or loss of ingredients. The concrete mix shall be so controlled that suitable workability at the forms will be obtained at all times without the use of excessive water. Design of the transporting equipment shall be of such a nature as to allow discharge of the concrete into the forms at all heights of the stacks without addition of excessive water. Concrete shall be placed before initial set has occurred and unless otherwise authorized not more than 45 minutes after introduction of water to the cementitious materials.

C- 3.14 TRIAL OPERATION

Not less than 10 days prior to commencement of concrete placing, a test of the batching and mixing plant shall be made in order to check operational efficiency. If the plant is the same as used on the previous contract and has not been moved, testing shall be performed not less than 8 days prior to commencement of placing concrete. The number of full-scale concrete batches required to be produced in trial runs will not exceed 10 and shall be proportioned as directed by the Contracting Officer. During these trial runs, the Government will make these cylinders, as necessary, to field adjust the design mix before production of mat begins. A minimum of one uniformity test will be performed on one of the test batches during the initial trial operation of the plant. Additional uniformity tests will be performed if necessary to establish acceptable operation of the plant, or where required by other contract provisions. All other concrete produced in these tests shall be wasted in low areas of the casting field and incorporated into the field surface. All deficiencies found in plant operation shall be corrected to the satisfaction of the Contracting Officer prior to start of concrete placing operations. No separate payment will be made to the Contractor for plant, labor or materials required by the provisions of this paragraph.

C- 3.15 CASTING

C- 3.15.1 General

Squares of mattress shall be cast in stacks as indicated on the drawings.

The stacks shall be neatly aligned vertically and by rows. At the beginning of casting operations, if there are stacks that have not been brought to the required height, the Contractor will be required to complete these stacks first. When the Contractor approaches completion of the

DOCUMENT 00 90 00 Page 18 casting operations, he shall schedule concrete placements in order to complete the casting operation with no incomplete stacks.

C- 3.15.2 Casting Procedure

C- 3.15.2.1 Paper Installation

One layer of the specified paper shall be placed as a separation beneath the bottom square of each stack and between each successive layer of mattress. Before the paper is spread, preparatory to reassembling the forms, the top surface of the concrete square shall be swept clean of loose gravel and debris. When determined necessary by the Contracting Officer, paper that is wet shall be removed and replaced with dry paper before placing concrete, at no additional cost to the Government.

C- 3.15.2.2 Form Placement

Forms shall be placed sufficiently in advance of concrete placement to allow time (a minimum of 15 minutes) for inspection and minor adjustments of forms and fabric, if required. Forms shall not be placed upon a previously cast square of mattress until the concrete has obtained sufficient strength to withstand possible damage by the form. Normally this time will be 3 hours or more, depending upon the use of calcium chloride, weather, and temperature conditions. This time could vary considerably. The placement procedure shall be as follows:

i The wire mesh shall first be placed on the paper with the cross wires (bracket wires) on top of the longitudinal wires. The forms shall then be placed over the wire mesh, the wire mesh drawn up into the notches in the sides and cross pieces of the forms and cross rods driven. The cams have been welded into the open position. Because of this, the contractor must manually pull the wire mesh and secure it in its proper position, which is located in the center of the 3 inch layer of concrete and does not exceed more than a half inch above or below the central plane of the form section. If the contractor cannot meet the specified tolerances for the wire mesh placement, the contractor shall use metal or plastic chairs that are approved by the Contracting Officer at no additional expense to the Government to temporarily hold the wire mesh in the approved position and meet the tolerance while completing the square. The wire mesh shall be located at an equi-distant from each end of the casting form. The central location of the wire mesh in the form is very important. The Contractor shall use all loose or broken bundles of wire mesh before opening a new bundle.

Completed mattress squares in which the wire mesh is more than one-half (1/2) inch above or below the center of the square will be rejected.

Adjustments to the wire mesh such as adding a chair, blocking or crimping of the wire mesh to secure proper alignment in the form shall be made at no additional expense to the Government.

ii Plastic or Metal chairs shall be placed under the outer edge of each end loop inside the form (resulting in four chairs per square).

Chairs shall hold the wire fabric in the center of the three-inch layer of concrete at a height of 1-1/2 inches from the top of paper.

iii Corner reinforcement shall be placed and tied to the wire mesh utilizing plastic zip ties or stainless steel approved equal. Corner reinforcement shall be placed to ensure reinforcement extends into the

DOCUMENT 00 90 00 Page 19 corner and tied to the intersection of the wire mesh to minimize movement during placement of concrete. Corner reinforcement to be ALP Supply, model BSSBT112 or approved equal. Reinforcement must be cut into four (4) - 15 inch sections.

All squares which have corner reinforcement shall all be stamped with a (CR) in the same manner identified in Paragraphn 3.15.2.10 Marking Mat.

All squares utilizing corner reinforcement shall be cast at the beginning of the casting season within the first 50,000 squares.

Completed mattress squares in which the fabric has sagged too near the bottom surface of the square will be rejected. Adjustments to the fabric such as blocking or crimping of the fabric to secure proper alignment in the form shall be made at no additional expense to the Government.

C- 3.15.2.3 Form Release Agent - Other Than Commercial Products

C- 3.15.2.3.1 General

If the form release agent proposed for use is other than a commercial product manufactured specifically for this purpose, the Contractor shall provide results of quantitative analyses of the proposed release agent for hazardous waste characteristics identified in 40 CFR 261, Subpart C; for polychlorinated biphenyls (PCBs); and for total halogens. If the Contractor elects to use used oil as a form release agent, the Contractor shall abide by 40 CFR 279 where applicable in the management of the used oil. Additionally, the Contractor shall be required to provide written certification that the material does not contain listed hazardous waste.

All analytical results shall be submitted to the Contracting Officer for approval.

C- 3.15.2.3.2 Acceptance Criteria

Materials exhibiting RCRA hazardous characteristics as defined in 40 CFR 261, Subpart C, materials with the potential to exhibit RCRA hazardous characteristics based on total concentrations, and materials containing listed hazardous waste as defined in 40 CFR 261, Subpart D are not acceptable for use as a form release agent.