June 1, 2017 PARTIES INTERESTED IN POST-TENSIONING ANCHORAGES AND COUPLERS OF PRESTRESSED CONCRETE

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1 June 1, 2017 TO: PARTIES INTERESTED IN POST-TENSIONING ANCHORAGES AND COUPLERS OF PRESTRESSED CONCRETE SUBJECT: Proposed Revisions to the Acceptance Criteria for Post-Tensioning Anchorages and Couplers of Prestressed Concrete, Subject AC R1 (RW/RK) Dear Colleague: We are seeking your comments on proposed revisions to the subject acceptance criteria, as presented in the enclosed draft. The revisions, which are being posted on the ICC-ES web site for 30 days of public comment, may be summarized as follows: 1. Addition of the 2015 International Building Code (IBC) and updating reference standards. 2. Addition of reference to PTI M Specification for Unbonded Single Strand Tendons for encapsulated tendons with sheathing overlap connection or sheathing restraint connection. 3. Revise Section 1.4 of the acceptance criteria to include new definitions and reorganize definitions to be in alphabetical order. 4. Revise Section of the acceptance criteria to include the tension stress levels in the fatigue tests that will be required for evaluation under the 2015 IBC, since the tension stress levels of 40 and 85 percent of the strand s minimum specified tensile strength specified in ACI differ from those required for evaluation under older code editions. Because the new 85 percent stress level is more stringent than the previous requirement of 80 percent, existing report holders will need to retest or submit test data/analysis for evaluation under the 2015 IBC, if their currently evaluated products were tested at the 80 percent stress level. 5. Revisions to address encapsulation of the post-tensioning anchorages, couplers and strands for evaluation under the 2015 IBC, since ACI , referenced by the 2015 IBC, requires the tendons to be protected against corrosion by encapsulation. Although some testing for encapsulated tendons are included in Section 3.0 of the attached proposed revisions to the acceptance criteria, the reference standards do not provide sufficient details. We are seeking input from all interested parties on the following:

2 AC R1 2 a. Material types and specifications for the material used to encapsulate the anchors and couplers. b. Strength and durability requirements for the material encapsulating the anchors and couplers, including test procedures and conditions of acceptance, to demonstrate that the material can withstand damage due to installation, concrete placement and stressing. c. Test setups and testing apparatus for hydrostatic testing of the encapsulated anchorages and couplers. d. Should encapsulation of tendons also be required for products evaluated for use in slab-on-ground foundations on expansive soils under Section of the acceptance criteria? If they are of interest, please review the proposed revisions and send us your comments at the earliest opportunity. At the end of the 30-day comment period, we will post on our web site the correspondence we have received. We hope your comments will help us prepare a final set of revisions for the Evaluation Committee to consider at a future hearing. To submit your comments, please use the form on the web site and attach any letters or other materials. If you would like an explanation of the alternate criteria process, under which we are soliciting comments, this too is available on the ICC-ES web site. Please do not try to communicate directly with any Evaluation Committee member about a criteria under consideration, as committee members cannot accept such communications. Thank you for your interest and your contributions. If you have any questions, please contact me at (800) , extension 3221, or Russ Krivchuk, P.E., Regional Engineering Director, at extension You may also reach us by at es@icces.org. Yours very truly, RW/raf Encl. cc: Evaluation Committee Richard Wang Senior Evaluation Specialist

3 (800) (562) A Subsidiary of the International Code Council PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR POST- TENSIONING ANCHORAGES AND COUPLERS OF PRESTRESSED CONCRETE AC303 Proposed June 2017 Previously approved April 2011, October 2006, September 2006, February 2005 (Previously editorially revised March 2014, August 2012) PREFACE Evaluation reports issued by ICC Evaluation Service, LLC (ICC-ES), are based upon performance features of the International family of codes. (Some reports may also reference older code families such as the BOCA National Codes, the Standard Codes, and the Uniform Codes.) Section of the International Building Code reads as follows: The provisions of this code are not intended to prevent the installation of any materials or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved. An alternative material, design or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code in quality, strength, effectiveness, fire resistance, durability and safety. ICC-ES may consider alternate criteria for report approval, provided the report applicant submits data demonstrating that the alternate criteria are at least equivalent to the criteria set forth in this document, and otherwise demonstrate compliance with the performance features of the codes. ICC-ES retains the right to refuse to issue or renew any evaluation report, if the applicable product, material, or method of construction is such that either unusual care with its installation or use must be exercised for satisfactory performance, or if malfunctioning is apt to cause injury or unreasonable damage. Acceptance criteria are developed for use solely by ICC-ES for purpose of issuing ICC-ES evaluation reports. Copyright 2017 ICC Evaluation Service, LLC. All rights reserved.

4 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR POST- TENSIONING ANCHORAGES AND COUPLERS OF PRESTRESSED CONCRETE (AC303) 1.0 INTRODUCTION 1.1 Purpose: The purpose of this acceptance criteria is to establish requirements for post-tensioning anchorages and couplers of prestressed concrete to be recognized in an ICC Evaluation Service, LLC (ICC-ES), evaluation report under the 2015, 2012 and 2009 International Building Code (IBC). The reason for development of this criteria is to establish guidelines for the evaluation of post-tensioning anchorages and couplers of prestressed concrete, since the IBC addresses these products, but does not provide sufficient testing details. 1.2 Scope: This criteria allows two applications for the post-tensioning anchorages and couplers General Use: This criteria is applicable to anchorages and couplers of unbonded, monostrand (single-strand), post-tensioning tendons in prestressed concrete designed in accordance with Chapter 25 of ACI (Chapter 18 of ACI or -08) under the provisions of Section of the IBC. This criteria applies to anchorages and couplers complying with Sections , and (a) of ACI (Sections and of ACI or -08), which requires monostrand anchorage devices to comply with ACI Under the 2015 IBC, all tendons are required to be protected against corrosion by encapsulation Slab-on-ground Foundations on Expansive Soils: This criteria is also applicable to anchorages and couplers of unbonded, monostrand (single-strand), posttensioning tendons in prestressed concrete slab-onground foundations on expansive soils regulated under IBC Section ; and 2015 and 2012 IBC Sections 1904 and 1907 (2009 IBC Sections 1904 and 1910 in the 2009 IBC) as referenced in IBC Section Under the 2015 IBC, this criteria is applicable to post-tensioned concrete foundations with moments, shears and deflections used in the design based on PTI DC10.5. Section of PTI DC10.5 refers to PTI M10.2 for tendon requirements. Under the 2012 and 2009 IBC, This this criteria is applicable to post-tensioned concrete foundations with moments, shears and deflections used in the design based on PTI Standard Requirements for Analysis of Shallow Concrete Foundations on Expansive Soils, with the foundation designed in accordance with PTI Standard Requirements for Design of Shallow Post- Tensioned Concrete Foundations on Expansive Soils. Sections and 6.3 of PTI Standard Requirements for Design of Shallow Post-Tensioned Concrete Foundations on Expansive Soils refers to Sections 2.2 and 2.2.6, respectively, of PTI Specifications for Single-strand Unbonded Tendons, for anchorage and coupler requirements. 1.3 Codes and Reference Standards: , 2012 and 2009 International Building Code (IBC), International Code Council ACI 318 (-14 for the 2015 IBC, -11 for the 2012 IBC, -08 for the 2009 IBC), Building Code Requirements for Structural Concrete, American Concrete Institute. Page 2 of ACI (-14 for the 2015 IBC, -07 for the 2012 and 2009 IBC), Specification for Unbonded Single- Strand Tendons, American Concrete Institute ASTM A416 (-12a for the 2015 IBC, -10 for the 2012 IBC, -06 for the 2009 IBC), Standard Specification for Steel Strand, Uncoated Seven-Wire for Prestressed Concrete, ASTM International ASTM A or 02 01, Test Methods and Definitions for Mechanical Testing of Steel Products, ASTM International ASTM A , Standard Test Methods for Testing Multi-Wire Steel Strand, ASTM International Specifications for Single-Strand Unbonded Tendons, May 2003, Post Tensioning Institute (PTI) Standard Requirements for Analysis of Shallow Concrete Foundations on Expansive Soils, 3 rd edition, 2007, PTI Standard Requirements for Design of Shallow Post-Tensioned Concrete Foundations on Expansive Soils, 2 nd edition, 2007, PTI PTI DC , Standard Requirements for Design and Analysis of Shallow Concrete Foundations on Expansive Soils, PTI PTI M , Specification for Unbonded Single Strand Tendons, PTI. 1.4 Definitions: Anchorage: For definition of anchorage, see Section 2.1 of ACI (Section 1.2 of ACI ) and Section 1.2 of the PTI Specification for Unbonded Single Strand Tendons. The components of the anchorage typically consist of a steel casting and wedges Anchorage Device: See Section of this criteria for definition of anchorage. Note: ACI 318 uses the term anchorage device, and ACI uses the term anchorage Coupler: For definition of coupler, see Section 2.1 of ACI (Section 1.2 of ACI ) and Section 1.2 of the PTI Specification for Unbonded Single Strand Tendons. The components of the coupler typically consist of a steel coupler and wedges Encapsulated Tendon: For definition of encapsulated tendon, see Section 2.1 of ACI (Section 1.2 of ACI ) and Section 1.2 of the PTI Specification for Unbonded Single Strand Tendons Monostrand Anchorages: Monostrand anchorages utilize a single strand per anchorage Post-Tensioning Coating: For definition of post-tensioning coating, see Section 2.1 of ACI (Section 1.2 of ACI ) and Section 1.2 of the PTI Specification for Unbonded Single Strand Tendons Sheathing: For definition of sheathing, see Section 2.1 of ACI (Section 1.2 of ACI ) and Section 1.2 of the PTI Specification for Unbonded Single Strand Tendons.

5 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR POST-TENSIONING ANCHORAGES AND COUPLERS OF PRESTRESSED CONCRETE (AC303) Sheathing Overlap Connection: For definition of sheathing overlap connection, see Section (c) of the PTI M Sheathing Restraint Connection: For definition of sheathing restraint connection, see Section (d) of the PTI M Strands: Strands are uncoated seven-wire steel strands complying with ASTM A416. The strand types are either low-relaxation strand or stress-relieved (normal-relaxation) strand. The grade of the strands is either Grade 250 or Grade Tendon: For definition of tendon, see Section 2.1 of ACI (Section 1.2 of ACI ) and Section 1.2 of the PTI Specification for Unbonded Single Strand Tendons Strands: Strands are uncoated seven-wire steel strands complying with ASTM A416. The strand types are either low-relaxation strand or stress-relieved (normalrelaxation) strand. The grade of the strands is either Grade 250 or Grade Monostrand Anchorages: Monostrand anchorages utilize a single strand per anchorage Anchorage: For definition of anchorage, see Section 1.2 of ACI and Section 1.2 of the PTI Specifications for Single-Strand Unbonded Tendons. The components of the anchorage typically consist of a steel casting and wedges Anchorage Device: See Section of this criteria for definition of anchorage. Note: ACI 318 uses the term anchorage device, and ACI uses the term anchorage Tendon: For definition of tendon, see Section 1.2 of ACI and Section 1.2 of the PTI Specifications for Single-Strand Unbonded Tendons Coupler: For definition of coupler, see Section 1.2 of ACI and Section 1.2 of the PTI Specifications for Single-Strand Unbonded Tendons. The components of the coupler typically consist of a steel coupler and wedges. 2.0 BASIC INFORMATION 2.1 General: The following information shall be submitted: Product Description: Complete descriptive information of the anchorage devices, couplers and wedges, including the following, needs to be submitted and included in the quality control manual required under Section 5.1: Material specifications of components Specifications of final product, including fully dimensioned drawings with tolerances A description of the manufacturing process Installation Instructions: Installation instructions, including limitations, and fastening methods and anchorage-to-sheathing connection method for encapsulated tendons Packaging and Identification: A description of the method of packaging and field identification of the Page 3 of 5 anchorage devices, couplers and wedges. Labels on the containers of the anchorage devices, couplers and wedges shall include the company name and address, evaluation report number (ESR-XXXX), model designation (when applicable), and serial number or date code for traceability Field Preparation: A description of the methods of field-preparation of the anchorage devices, couplers and wedges for installation. 2.2 Testing Laboratories: Testing laboratories shall comply with Section 2.0 of the ICC-ES Acceptance Criteria for Test Reports (AC85) and Section 4.2 of the ICC-ES Rules of Procedure for Evaluation Reports. 2.3 Test Reports: Reports of tests required under Section 3.0 of this criteria shall comply with AC85 and also include the following: Description of the anchorage device, coupler, and wedge test specimens, including dimensioned drawings of the tested products and sufficient information to ascertain compliance of the tested products with the product specifications in the manufacturer s quality control manual Data on the actual physical properties of the tested anchorages and couplers Copy of mill certificates or reports of coupon tests that include the actual tensile strength of the strand used in the tests conducted under this criteria Description of the test setup sufficient to ascertain compliance with this criteria. 2.4 Product Sampling: Sampling of the anchorage devices, couplers and wedges for qualifying tests conducted under this criteria shall comply with Section 3.2 of AC85. The testing laboratory shall witness the assembly of the test specimens. 3.0 TEST AND PERFORMANCE REQUIREMENTS 3.1 General: The strand used in the tested assemblies shall be of the type and grade of strand specified by the evaluation report applicant to be noted in the evaluation report. The mechanical properties of the strand used in the load tests shall be established by tests conducted in accordance with either ASTM A1061 as referenced by ASTM A416-12a or -10 or ASTM A 370 as referenced by ASTM A The static and fatigue load tests shall be conducted as a series, with strand used in all tests from the same coil and/or having the same heat number. Anchorages and couplers shall be subjected to the static load tests and fatigue load tests of Sections 3.2 and 3.3. Encapsulated tendons with a sheathing overlap connection shall also be subjected to the durability and hydrostatic tests of Sections 3.4 and 3.5. Encapsulated tendons with a sheathing restraint connection shall also be subjected to the durability, hydrostatic and anchorage-tosheathing connection tests of Sections 3.4 through Static Load Tests: General: Static load tests of the tendons shall be conducted in accordance with Section 4.1 of this criteria. The tests shall be conducted on a minimum of three tendons for each anchor (or coupler, as applicable)

6 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR POST-TENSIONING ANCHORAGES AND COUPLERS OF PRESTRESSED CONCRETE (AC303) that is to be included in the evaluation report. For anchorages, the tests shall be conducted on assemblies (tendons) consisting of the anchorage device, wedges and strand with anchorages at each end of the tested assembly. For couplers, the tests shall be conducted on assemblies consisting of a coupler with strand at each end of the coupler. An anchorage may be utilized at the end of each strand of the coupler test assembly to facilitate application of load to the assembly. The tested assemblies shall not include concrete Conditions of Acceptance: The conditions of acceptance are that each test assembly shall demonstrate failure of the strand at a test load of at least 95 percent of the actual tensile strength of the strand used in the tests. In addition, the elongation of the strand of each tested assembly at the ultimate load shall be at least 2 percent. For tests of couplers, the strand elongation requirement is applicable to the strand at each end of the coupler. 3.3 Fatigue Load Tests: General: The 50- and 500,000-cycle fatigue load tests of Section 4.2 shall be conducted on a minimum of two tendons for each test series for each anchorage (or coupler, as applicable) that is to be included in the evaluation report. The tests shall be conducted on assemblies (tendons) consisting of the anchorage (or coupler, as applicable), wedges and strand. For anchorages, the anchorage shall be installed at each end of the tested assembly. For couplers, the test assemblies shall have a strand at each end of the coupler. An anchorage may be utilized at the end of each strand of the coupler test assembly to facilitate application of load to the assembly. The tested assemblies shall not include concrete. The specimens subjected to the 50-cycle fatigue load test need not be the same specimens subjected to the 500,000- cycle fatigue load test Conditions of Acceptance: The conditions of acceptance of the dynamic load tests are that the specimens shall withstand the dynamic loads without failure. 3.4 Durability Test: The encapsulation material shall comply with the following requirements: (The staff is requesting industry comments and suggestions regarding the durability testing of the encapsulation material as noted in the cover letter to this drafted proposed revisions to the acceptance criteria.) 3.5 Hydrostatic Tests: For encapsulated tendons with sheathing overlap connection, hydrostatic testing of the encapsulated tendons shall comply with Section 9.6 of ACI For encapsulated tendons with sheathing restraint connection, hydrostatic testing of the encapsulated tendons shall comply with Section of PTI M Anchorage-to-Sheathing Connection Test: For encapsulated tendons with a sheathing restraint connection, testing in accordance with Section of PTI M10.2 is required. Page 4 of TEST METHODS 4.1 Static Load Tests: The static load tests are static tension load tests of the tendons. For tests of anchorages, the tendons shall have a minimum length of 3.5 feet (1067 mm) between anchorages such that the elongation of the strand is measured with a 3-foot (914 mm) minimum gage length measured between two points on the strand at least 3 inches (76 mm) from the anchorage at each end of the tendon. For tests of couplers, the elongation of both strands of each test assembly shall be measured over a 3- foot (914 mm) minimum gage length on each strand with the points of measurement at least 3 inches (76 mm) from the coupler and test apparatus attachment point or anchorage, if used, on the end of the strand. The tests shall be conducted such that the yield strength and tensile strength of the tested assembly and the percent elongation of the strand of each tested assembly are determined. The tension load shall be applied to the anchorage devices at each end of the assembly. For tests of couplers, without anchorages on the ends of the strand, the tension load shall be applied to the strand at each end of the assembly. The tests shall be conducted with a test machine head separation rate of to inch per minute (5.00 to 22.5 mm/min), following application of a preload not to exceed 1000 pounds (4.45 kn). 4.2 Fatigue Load Tests: General: For tests of anchorages, the minimum assembled tendon length of the fatigue load test specimens shall be 3 feet (914 mm) between anchorage devices. The tendon length of coupler test assemblies shall be such that there is a 3-foot (914 mm) minimum length of strand at each end of the coupler. The loads shall be applied to the anchorage device at each end of the assembly. For tests of couplers without anchorages on the ends of the strand, the tension load shall be applied to the strand at each end of the assembly. The loads shall be applied to the test assemblies using a sinusoidal loading function Cycle Fatigue Load Test: IBC: For recognition under the 2015 IBC, the 50-cycle fatigue load test shall consist of subjecting the tendons to 50 cycles of varying the tension stress level in the tendon between 40 and 85 percent of the strand s minimum specified tensile strength. The cycle frequency shall be 1 to 3 Hertz and 2009 IBC: For recognition under the 2012 and 2009 IBC, The the 50-cycle fatigue load test shall consist of subjecting the tendons to 50 cycles of varying the tension stress level in the tendon between 40 and 80 percent of the strand s minimum specified tensile strength. The cycle frequency shall be 1 to 3 Hertz ,000 Cycle Fatigue Load Test: The 500,000-cycle fatigue load test shall consist of subjecting the tendons to 500,000 cycles of varying the tension stress level in the tendon between 60 and 66 percent of the strand s specified minimum tensile strength. The cycle frequency shall be 1 to 10 hertz. 5.0 QUALITY CONTROL 5.1 Quality documentation complying with the ICC-ES Acceptance Criteria for Quality Documentation (AC10), regarding the manufacturing of the post-tensioning

7 PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR POST-TENSIONING ANCHORAGES AND COUPLERS OF PRESTRESSED CONCRETE (AC303) anchorages, couplers and wedges, shall be submitted for each facility manufacturing or labeling products that are recognized in the ICC-ES evaluation report. The purpose of the quality control program shall be to assure that anchorages, couplers and wedges manufactured under the program continue to comply with the IBC and this criteria, for structural performance. The manual needs to include the information required by Section A qualifying inspection shall be conducted at each manufacturing facility in accordance with the requirements of the ICC-ES Acceptance Criteria for Inspections and Inspection Agencies (AC304). 5.3 An annual inspection shall be conducted at each manufacturing facility in accordance with AC Regular, ongoing inspections of the manufacturing of the anchorages, couplers and wedges are not required under this acceptance criteria; but the manufacturing facilities may be subject to annual inspections in accordance with Section 9.0 of the ICC-ES Rules of Procedure for Evaluation Reports. 6.0 EVALUATION REPORT RECOGNITION 6.1 The evaluation report shall include a statement that the prestressed concrete shall be designed in accordance with Chapter 25 of AC (Chapter 18 of ACI or -08), with the anchorage zones designed in accordance Section (a) of ACI (Section of ACI or -08). 6.2 The evaluation report shall state that the strand shall comply with ASTM A 416 A416, and specify the strand diameter, type and grade consistent with the tested assemblies. 6.3 The evaluation report shall state that special inspection shall be provided for the installation and stressing of the tendons, including verification of concrete compressive strength at the time the tendons are stressed. The special inspector shall verify compliance with the design engineer s requirements, including prestressing instructions, checking elongation and jacking force parameters, and the sequence of tendon stressing, as well as end and edge distance and tendon spacing dimensions. Page 5 of 5