31_68_14_Pre-Grouted_Bar_Anchors.pdf

SECTION 31 68 14

PRE-GROUTED BAR ANCHORS

06/10

PART 1 GENERAL

1.2 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 INTERNATIONAL (ACI)

ACI 301 (2016) Specifications for Structural Concrete

ACI 318 (2014; Errata 1-2 2014; Errata 3-5 2015;

Errata 6 2016) Building Code Requirements for Structural Concrete and Commentary

ACI 318M (2014; ERTA 2015) Building Code Requirements for Structural Concrete & Commentary

ACI SP-66 (2004) ACI Detailing Manual

AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

(AASHTO)

AASHTO M 252 (2009; R 2012) Standard Specification for Corrugated Polyethylene Drainage Pipe

AMERICAN INSTITUTE OF STEEL CONSTRUCTION (AISC)

AISC 325 (2011) Steel Construction Manual

AMERICAN PETROLEUM INSTITUTE (API)

API Spec 5CT (2011; Errata 2012) Specification for Casing and Tubing

ASTM INTERNATIONAL (ASTM)

ASTM A108 (2013) Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished

ASTM A36/A36M (2014) Standard Specification for Carbon Structural Steel

ASTM A416/A416M (2016) Standard Specification for Steel Strand, Uncoated Seven-Wire for Prestressed Concrete

ASTM A500/A500M (2013) Standard Specification for Cold-Formed Welded and Seamless Carbon

Steel Structural Tubing in Rounds and Shapes

ASTM A53/A53M (2012) Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded and Seamless

ASTM A536 (1984; R 2014) Standard Specification for Ductile Iron Castings

ASTM A572/A572M (2015) Standard Specification for High-Strength Low-Alloy Columbium-Vanadium Structural Steel

ASTM A588/A588M (2015) Standard Specification for High-Strength Low-Alloy Structural Steel with 50 ksi (345 MPa) Minimum Yield Point, with Atmospheric Corrosion Resistance

ASTM A615/A615M (2016) Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement

ASTM A709/A709M (2016a) Standard Specification for Structural Steel for Bridges

ASTM A722/A722M (2015) Standard Specification for Uncoated High-Strength Steel Bar for Prestressing Concrete

ASTM A775/A775M (2016) Standard Specification for Epoxy-Coated Steel Reinforcing Bars

ASTM A779/A779M (2016) Standard Specification for Steel Strand, Seven-Wire, Uncoated, Compacted, Stress-Relieved for Prestressed Concrete

ASTM A882/A882M (2004a; R 2010) Standard Specification for Filled Epoxy-Coated Seven-Wire Prestressing Steel Strand

ASTM A981/A981M (2011; R 2016) Standard Test Method for Evaluating Bond Strength for 0.600-in.

[15.24 mm] Diameter Steel Prestressing Strand, Grade 270 [1860], Uncoated, Used in Prestressed Ground Anchors

ASTM C109/C109M (2016a) Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or (50-mm) Cube Specimens)

ASTM C1107/C1107M (2014a) Standard Specification for Packaged Dry, Hydraulic-Cement Grout (Nonshrink)

ASTM C144 (2011) Standard Specification for

Aggregate for Masonry Mortar

ASTM C150/C150M (2016; E 2016) Standard Specification for Portland Cement

ASTM C33/C33M (2016) Standard Specification for Concrete Aggregates

ASTM C39/C39M (2016b) Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens

ASTM C494/C494M (2016) Standard Specification for Chemical Admixtures for Concrete

ASTM C70 (2013) Standard Test Method for Surface Moisture in Fine Aggregate

ASTM C940 (2016) Standard Test Method for Expansion and Bleeding of Freshly Mixed Grouts for Preplaced-Aggregate Concrete in the Laboratory

ASTM D1248 (2012) Standard Specification for Polyethylene Plastics Extrusion Materials for Wire and Cable

ASTM D1784 (2011) Standard Specification for Rigid Poly(Vinyl Chloride) (PVC) Compounds and Chlorinated Poly(Vinyl Chloride) (CPVC) Compounds

ASTM D1785 (2012) Standard Specification for Poly(Vinyl Chloride) (PVC), Plastic Pipe, Schedules 40, 80, and 120

ASTM D3350 (2012) Polyethylene Plastics Pipe and Fittings Materials

ASTM D4101 (2014; E 2016) Standard Specification for Polypropylene Injection and Extrusion Materials

ASTM E139 (2011) Standard Test Methods for Conducting Creep, Creep-Rupture, and Stress-Rupture Tests of Metallic Materials

AMERICAN WELDING SOCIETY (AWS)

AWS D1.5M/D1.5 (2015) Bridge Welding Code

POST-TENSIONING INSTITUTE (PTI)

PTI 4 (June 1996) Recommendations for Prestressed Rock and Soil Anchors

PTI A (Nov 1990) Post-Tensioning Manual

PTI Acc (1998) Acceptance Standards for Post-Tensioning Systems

PTI Rec (2004, Fourth Edition) Recommendations for Prestressed Rock and Soil Anchors

PTI Spec (2000, Second Edition) Specifications for Unbonded Single Strand Tendons

PTI Post Ten Man (2006, Sixth Edition) Post-Tensioning Manual

PTI TAB.1 (2006) Post-Tensioning Manual

U.S. ARMY CORPS OF ENGINEERS (USACE)

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

EM 1110-2-2105 (1994) Engineering and Design - Design of Hydraulic Steel Structures

EM 385-1-1 (2014) Safety and Health Requirements Manual

1.2 UNIT PRICES

1.2.1 Post-Tensioned Anchor Bars, Complete

1.2.1.1 Payment

Payment for all work covered by this section will be made at the applicable contract unit price for "Post-Tensioned Anchor Bars, Complete," which price shall be full compensation for fabricating and furnishingpost-tensioned anchor bars which are accepted. No payment will be made for anchors which do not meet the acceptance criteria.

1.2.1.2 Measurement

Post-Tensioned Anchor Bars, Complete will be measured based upon the number of anchors and accepted in accordance with the specifications.

1.2.1.3 Unit of Measure

Unit of measure: Each.

1.3 DEFINITIONS

The following definitions are in addition to those given in PTI TAB.1:

Post-Tensioned Anchor Bars - (herein after referred to as "anchor bars") refers to the use of a soil and rock anchor as an anchor bar for a structure with the grouted development length located within mass concrete.

Demonstration Test Anchor - An anchor which is performance tested to verify design assumptions and installation practices.

1.4 SYSTEM DESCRIPTION

1.4.1 General Requirements

The work includes design and fabrication of the bar anchor system. The Contractor shall be responsible for developing an Anchor Bar Post-Tensioning Plan. The anchors shall be fabricated as shown on the drawings. The Contractor shall be responsible for the design of the anchor head, nut and washer, grout tube configuration, grouting procedure, centralizers, and corrosion protection. The complete designs, including design computations, fabrication and installation drawings, installation and testing plans, shall be sealed by a Professional Engineer registered in the State of Tennessee, and shall be submitted for approval. Approval of the design by the Contracting Officer will not relieve the Contractor of responsibility for design and performance of the bar anchors. The materials, stressing, load testing, and acceptance shall be in accordance with PTI Recommendations and these specifications. Bar anchors shall be epoxy coated threaded bar type.

1.5 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-02 Shop Drawings

Fabrication Drawings; G|GG

The design shall include: drawings; anchor fabrication;

grouting methods; grout mix designs; anchor placement and installation; corrosion protection for bond length, stressing length, and anchorage; stressing and testing procedures with lengths, forces, deformations, and elongations for the approval by the Contracting Officer. Shop drawings for anchors shall include locations and details of the centralizers, grout tubes, vent tubes and banding. Once reviewed by the Contracting Officer, no changes or deviation from shop drawings shall be permitted without further review by the Contracting Officer.

SD-03 Product Data

Designer Qualifications; G|GG Fabricator Qualifications; G|GG

Anchor Bar Installation Plan; G|GG

The Contractor shall submit to the Contracting Officer, for review and comment, a plan for installing the bar anchors. The proposal shall describe the sequence for installation and other restrictions as outlined on the drawings or specified. The anchor bar installation procedures shall be determined by the Contractor as part of the anchor system. The installation plan shall also include grouting procedures for the corrugated tubing, method for inspecting and repairing bar corrosion protection during installation, detailed procedures for securing an incomplete anchor, and descriptions of methods and equipment to be used by the Contractor for alignment checking of anchor holes during drilling and after each hole is complete.

Anchor Installation Schedule; G|D|G

The Contractor shall furnish an installation schedule for the anchors which includes the following:

. Anchor number

. Heat or lot numbers of the bar used to manufacture the anchor

. Bar Diameter

. Design Load

. Max Test Load

. Anchor lock-off load

. Total anchor length

. Bond length

. Bar bond length

. Unbonded length

. Details of corrosion protection, including details of anchorage and installation . Details of base plate, anchor head, nut and washer

The installation schedule shall be submitted at least 30 days of award of this contract.

Anchor Bar Post-Tensioning Plan; G|GG

SD-05 Design Data

Design Computations; G|D|G

The Contractor shall furnish design computations and data for the design of the pre-grouted anchor, anchor head, nut and washer, and centralizers. The computations shall include drawings, design assumptions, calculations, and other information in sufficient detail to verify the design proposed. The design shall be certified by a Professional Engineer registered in the State of Tennessee with proven experience in design of bar anchor systems as stated in Paragraph QUALIFICATIONS. Calculations shall be included for the stressing frames. The Contracting Officer will approve the Contractor's design calculations. Approval of the Contractor's design calculations will not relieve the Contractor of responsibility for unsatisfactory performance of the installed rock anchors or other Contractor-design elements. All design computations shall be furnished at least 30 calendar days of award of this contract.

SD-06 Test Reports

Prestressing Steel; G|D|G

The Contractor shall submit certified test reports for each heat or lot of prestressing steel with materials delivered to the site.

Cement Grout Mixture Proportions; G|G

The mixture proportions that will produce grout of the quality required shall be submitted. Applicable test reports shall be submitted to verify that the grout mixture proportions selected will produce grout of the quality specified.

SD-07 Certificates

Prestressing Steel; G|D|D

The Contractor shall submit five (5) copies of mill reports and five (5) copies of a certificate from the manufacturer stating chemical properties, ultimate strengths, yield strengths, modulus of elasticity, creep tests in accordance with ASTM E139, and any other physical properties needed for the required computations, for the type of steel furnished. These shall be submitted upon delivery of materials to the site. Information on the tags shall include the anchor number, heat numbers, number of bars, and lengths of each part of the anchor.

Epoxy-Coated Steel Bars

Written certification for coating material and coated bars with the delivery of the bars.

SD-11 Closeout Submittals

1.6 QUALIFICATIONS

The Contractor shall submit anchor designer and fabricatorqualifications for approval in accordance with Paragraph SUBMITTALS. The submittals shall, where applicable, identify individuals who will be working on this contract and their relevant experience. No changes shall be made in approved personnel without prior approval of the Contracting Officer.

1.6.1 Designer Qualifications

The anchorage assembly and anchorage recess shall be designed by registered Professional Engineers who have designed a minimum three anchorage systems similar in size and scope to this project within the past ten (10) years.

The drawings and calculations shall be signed and sealed by a registered Professional Engineer of the State of Tennessee.

1.6.2 Fabricator Qualifications

The anchors shall be fabricated by a manufacturer that has been in the practice of designing and fabricating bar anchors similar in size and scope to this project for at least ten (10) years.

1.6 PREPARATORY MEETING

Prior to commencing any work on the anchors, the Contractorshall meet with the Contracting Officer to review the Drawings and Specifications, work plans, and submittals within 15 calendar days after award of this contract.

1.7 DELIVERY, STORAGE, AND HANDLING

Materials shall be suitably wrapped, packaged or covered at the factory or shop to prevent being affected by dirt, water, oil, grease, and rust.

Protect materials against abrasion or damage during shipment and handling.

Place materials stored at the site above ground on a well supported platform and covered with plastic or other approved material. Materials shall be protected from adjacent construction operations. Grounding of welding leads to prestressing steel will not be permitted. Reject and remove from the site prestressing steel which is damaged by abrasion, cuts, nicks, heavy corrosions, pitting, welds or weld spatter. Inspect bars prior to insertion into anchor holes for damage to corrosion protection.

Any such damage shall be repaired in a manner recommended by the bar manufacturer and approved by the Contracting Officer. All stored materials and items shall be properly labeled to facilitate identification for inspection and retrieval.

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 Prestressing Steel

2.1.1.4 Epoxy-Coated Steel Bars

ASTM A722/A722M, Type I, conforming to the coating requirements of ASTM A775/A775M, 8 mils minimum thickness. Coating at the anchorage end shall be provided over the threads for the nut. Bars must be subjected to cold-stressing to not less than 80 percent Fpu.

2.1.2 Structural Steel

ASTM A572/A572M, Grade 50.

2.1.6 Polyethylene Tubing

2.1.6.1 Corrugated Polyethylene Tubing

AASHTO M 252, with average minimum wall thickness of at least 0.100-inch for tubing of diameter 10 inches or larger, and 0.06-inch for smaller tubing diameters. Depending on the Contractor's installation procedures and grout lift heights, the minimum wall thicknesses designated herein may not be sufficient to protect the encapsulation tubing against damage or collapse during installation. The Contractor shall select appropriate wall thicknesses in accordance with the approved design calculations.

2.1.7 Smooth Polypropylene Tubing

2.1.7.1 Polypropylene Tubing

ASTM D4101, designation PP 210 B5542-11.

2.1.8 Polyvinyl Chloride (PVC) Pipe

ASTM D1785, Schedule 40.

2.1.9 Polyvinyl Chloride (PVC) Tubing

2.1.9.1 Smooth Polyvinyl Chloride (PVC) Tubing

ASTM D1784.

2.1.9.2 Corrugated Polyvinyl Chloride (PVC) Tubing

Manufactured from rigid PVC compounds conforming to ASTM D1784, Class 13464-8 with average minimum wall thickness of 0.04-inch.

2.1.10 Heat Shrinkable Sleeve

Radiation crosslinked polyolefin tube internally coated with an adhesive sealant.

2.1.11 Corrosion Inhibiting Compound

The corrosion inhibiting compound shall conform to the requirements of PTI Rec.

2.2 MANUFACTURED UNITS

2.2.1 Anchor Head

Anchor head shall consist of steel bearing plate, and nut for bar anchors, and corrosion protection. Anchorage devices shall be capable of developing 95 percent of the guaranteed Fpu of prestressing steel. The anchorage devices shall conform to the static strength requirements of Section 3.1.6

(1) and Section 3.1.8 (1) and (2) of PTI TAB.1. Threaded anchorage items for epoxy coated bars shall be designed to fit over the epoxy coating and maintain the capacity of the prestressing steel. Threading for rods must be all right-handed.

2.2.2 Prestressing Steel Couplers

Prestressing steel couplers for bars shall be capable of developing 100 percent of the minimum specified Fpu of the prestressing steel.

2.2.3 Centralizers and Spacers

Centralizers and spacers shall be fabricated from plastic, steel or other approved material which is nondetrimental to the prestressing steel. Wood shall not be used. The centralizer shall be placed and spaced in accordance with the manufacturer's recommendations and be able to support the threadbar in the encapsulation pipe in the drill hole and position the threadbar so a minimum of 0.5-inch of grout cover is provided.

Centralizers and spacers shall permit grout to freely flow up the encapsulation pipe and hole. The lower end of the threadbar shall be fitted with a protective cap guide to facilitate insertion of the tendon into the encapsulation pipe without damaging the encapsulation pipe.

2.2.5 Anchorage Covers (Cap)

The anchor head shall be covered with a PTI-recommended anchorage cover.

The material used shall not be subject to attack by cement, corrosion-inhibiting compounds or the environment. The Contractor shall securely attach the cover to the anchor bar. A waterproof washer or o-ring shall be used to prevent the infiltration of water into the cover.

The cover shall be filled with a corrosion-inhibiting compound conforming to Table 4-1 of PTI Rec and shall form a permanent watertight enclosure for the anchorage device.

2.2.5 Temporary Waterproof Cover

The temporary waterproof cover for use when the Contractor is required to evacuate an incomplete anchor shall be fabricated from steel, and shall be capable of attaching to the lock wall in such a way as to form a watertight seal. The Contractor shall fabricate all covers necessary for the hole diameter that may need to be protected, and to have a sufficient number of covers with and without openings for anchor threadbars. At the discretion of the Contractor, the cover may include components that are left in place even while the cover is not in use, but removed prior to placement of concrete.

2.4 GROUT

2.4.1 Cement

The cement used in grout shall conform to ASTM C150/C150M, Type II.

2.4.2 Water

Water shall be fresh, clean, potable, and free from injurious amounts of sewage, oil, acid, alkali, salts, or organic matter, except that non-potable water may be used if it meets the requirements of COE CRD-C 400.

Water from the Tennessee River shall not be used for grouting unless treated so as to otherwise meet the requirements of this paragraph, as verified by laboratory tests conducted by an ERDC MTC Validated testing facility.

2.4.3 Aggregates

Fine aggregate for sand-cement grout shall conform to ACI 301 and ASTM C33/C33M for grout for backfilling holes or ASTM C144 for grout for waterproofing. Manufactured sand shall not be permitted. Aggregates shall not contain substances which may be deleteriously reactive with alkalies in the cement. Coarse aggregate for recess completion shall conform to ACI 301 and ASTM C33/C33M, with a maximum size of 1 inch

2.4.4 Admixtures

Non-shrink admixtures shall be used in all grout. Admixtures which control bleed, improve flowability, reduce water content and retard set may be used in the grout subject to the approval of the Contracting Officer. The use of bentonite as a thixotropic agent is not permitted. The use of accelerators is not permitted. Any admixtures used shall be compatible with the prestressing steel and shall be mixed in accordance with the manufacturer's recommendations. Performance of admixtures must be verified in conjunction with the Contractor's mix design.

2.4.5 Cement Grout for Anchors

Cement grout mixture proportions shall be the responsibility of the Contractor. Grout for grouting anchors shall consist of a homogenous, pumpable, low bleed, stable mixture of portland cement, water, and approved admixtures. The Contractor shall submit the proposed mix design and results of 6 compressive strength and 6 bleed tests, per batch, for 2 trial batches of the mix to the Contracting Officer for approval. Six (6) compressive strength tests shall be performed from grout mixed for placement at the outside annulus of the corrugated tubing, within the depths of the bond zone grout of each anchor. Results from the compressive strength tests shall be provided to the Contracting Officer prior to stressing of the anchor. Failure of grout to meet compressive strength or bleed requirements shall result in rejection of the anchor, as determined by the Contracting Officer. The Contractor shall replace rejected anchors at the same locations and inclinations as the rejected anchor. Anchor replacement shall be made at the Contractor's expense, at no additional cost to the Government. The water content shall be the minimum necessary for proper placement but the water-cement ratio shall not exceed 0.45 by weight. Bleeding of the grout mix shall be tested in accordance with ASTM C940. The 95 percent confidence interval from the bleed tests on each trial batch shall be less than 1 percent of the grout sample volume in 3 hours. Final proportions of materials shall be based on results of tests made on sample mixtures of grout. The minimum compressive strength of cylinders, molded, cured, and tested in accordance with ASTM C39/C39M, shall be [24.1] [_____] MPa 5,000 psi at the time of stressing. The Contractor shall be responsible for taking, curing, performing bleed tests, and breaking of grout test cylinders, and all sampling and testing activity shall be done by an independent, USACE Engineer Research and Development Center (ERDC) Materials Testing Center (MTC) Validated laboratory approved by the Contracting Officer. Concrete conditions and temperatures shall be replicated in the curing process.

2.4.6 Neat Cement Grout for Waterproofing or Backfilling Holes

Neat cement grout for waterproofing or backfilling holes shall consist of a homogenous, pumpable, stable mixture of portland cement and water. The grout mix proportions shall be the responsibility of the Contractor. The Contractor shall submit the proposed mix design to the Contracting Officer for approval. The water content shall be the minimum necessary for proper placement but the water-cement ratio shall not exceed 0.67 by weight. Final proportions of materials shall be based on results of tests made on sample mixtures of grout.

2.4.7 Sand-Cement Grout

Sand-cement grout for waterproofing holes and grouting holes which fail the watertightness test shall consist of a mixture of portland cement, fine aggregate and water. The grout mix proportions shall be the responsibility of the Contractor. The Contractor shall submit the proposed mix design to the Contracting Officer for approval. The water content shall be the minimum necessary for proper placement but the water-cement ratio shall not exceed 0.45. Final proportions of materials shall be based on results of tests made on sample mixtures of grout.

2.4.8 Grout for Anchor Frames

Grout for bearing under anchor frame bearing plates shall be in accordance with Section 03 30 53 MISCELLANEOUS CAST-IN-PLACE CONCRETE.

2.5 BAR ANCHOR FABRICATION

2.5.1 General

Fabrication of the anchors shall be as recommended by the suppliers.

Anchor bars shall be cold stretched to no less than 80 percent Fpu before pregrouting at the factory. Anchors shall be completely assembled with all centralizers, grout and vent tubes and corrosion protection prior to insertion into the hole. Anchor bars shall be pregrouted inside the encapsulation at the factory. Fabricated anchors shall be protected, transported and stored in a manner to prevent contamination or damage to any components. The Contractor shall use care in handling and storing the pre-grouted anchor at the site. Prior to inserting a pre-grouted anchor in the drill hole, the Contractor shall examine the encapsulation, sheathing and exposed portion of the epoxy coated anchor bar for damage. If, in the opinion of the Government, there is damage, the Contractor shall repair the damage in accordance with the anchor supplier's recommendations or replaced the anchor if the damage is not repairable. Lifting of the pre-grouted tendons shall not cause excessive bending, which can debond the prestressing steel from the surrounding grout.

2.5.2 Bar Anchors

Bar material shall be unblemished and free of pitting, nicks, grease, or injurious defects. To maintain the bar location within the hole, provide centralizers at a maximum of ten (10) foot intervals center-to-center throughout the length of the anchor. The entire bond length of the bar shall be free of dirt, lubricants, loose rust, corrosion-inhibiting coatings, except for epoxy coating, or other contaminants.

2.5.4 Vent Tubes

Vent tubes used during grouting operations, if necessary, shall be any appropriate type for the job, as recommended by the supplier of the anchors.

2.5.5 Grout Tubes

Grout tubes shall be polyethylene tubing or as recommended by the anchor manufacturer and approved by the Contracting Officer. Inside diameter of grout tubes shall be adequate to fully grout the entire hole. The tips of the grout tubes will be set at elevations that allow the grouting to occur from the bottom to the top of the zone being grouted. Extra grout tubes may be needed to ensure grout coverage.

2.5.6 Corrosion Protection

Corrosion protection shall be Class I Protection as described in PTI Rec, except where modified by this specification and the contract drawings.

Corrosion protection shall be provided for the entire anchor and shall include anchorages covers filled with corrosion-inhibiting compound and encapsulation of the free stressing length and bond length. The anchor annulus from the top of the load washer down to the top of the encapsulated grout shall be filled with a corrosion inhibiting compound.

2.5.5.1 Anchorage Protection

The anchorage cap shall be completely filled with corrosion inhibiting compound on the anchors.

2.5.6.4 Full Anchor Length Encapsulation

Full Anchor length encapsulation shall consist of corrugated polyethylene tubing capable of transferring stresses from the grout surrounding the prestressing steel to the bond length grout on the outside of the corrugated polyethylene tubing. The encapsulation shall be watertight. The minimum wall thickness shall be minimum 0.060-inch. The Contractor is responsible for ensuring the encapsulation is watertight and stays watertight through the entire anchor installation, stressing and grouting process. Care shall be taken during fabrication and installation not to compromise the integrity, or the watertightness of the encapsulation.

2.6 TESTS, INSPECTIONS, AND VERIFICATIONS

The Contractor shall have required material tests performed on prestressing steel and accessories by an approved laboratory to demonstrate that the materials are in conformance with the Specifications. Grout shall be sampled and tested in accordance with ASTM C109/C109M by a laboratory validated by the Engineering Research and Development Center (ERDC) Materials Testing Center (MTC). Two compression tests and two bleed tests shall be conducted on each lift of grout placed. These tests shall be at the Contractor's expense. Prestressing steel test results shall be furnished to the Contracting Officer prior to beginning fabrication of any anchors. Grout test results shall be provided to the Contracting Officer within 24 hours of testing.

PART 3 EXECUTION

3.9 ACCEPTANCE

3.9.1 General

Acceptance of anchors shall be determined by the Contracting Officer. The following criteria will be used in determination of the acceptability of each anchor:

a. Creep - Creep movement shall be evaluated using PTI Rec.

b. Movement - Apparent free length shall be calculated from the observed elastic movement in accordance with PTI Rec.

1. Minimum Apparent Free Length - The calculated free length shall be not less than eighty (80) percent of the designed free bar length plus the jack length. If the anchor does not meet this criteria, the anchor shall be restressed from the Alignment Load to the Test Load and the apparent free length shall be recalculated. If the anchor does not meet this criteria after 3 attempts (original plus 2 restresses), the anchor shall be rejected.

2. Maximum Apparent Free Length - The calculated free length shall be not more than 100 percent of the designed free bar length plus

50 percent of the bond length plus the jack length. If the anchor does not meet this criteria, and the cause of the behavior is not investigated and explained to the satisfaction of the Contracting Officer, the anchor shall be rejected.

3.9.2 Acceptance Report

The Contractor shall provide a qualified registered engineer to evaluate the anchor test results and determine the acceptability of the anchors in accordance with the criteria indicated above. A report of this determination shall be included in the submittal of the anchor records for each anchor as described in Paragraph SUBMITTALS. Final acceptance of each anchor will be made by the Contracting Officer. All tests shall be run in the presence of the Contracting Officer.

3.9.3 Replacement of Rejected Anchors

Any anchor that fails the performance or proof test or is rejected by the Contracting Officer shall be replaced. A replacement anchor, including removing the failed anchor and re-drilling the anchor hole, shall be provided by the Contractor at no additional expense to the Government. The location of the replacement anchor shall be as directed by the Contracting Officer. The Contractor shall provide all materials, supplies, and labor necessary to provide a new anchor assembly to the satisfaction of the Contracting Officer. All specifications describing all aspects of the original anchor shall also be applicable to the replacement anchor.

Payment will not be made for rejected or failed anchors.

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