IAPMO ES
Cover Sheet
Evaluation Criteria of
MECHANICALLY ATTACHED ANCHOR NUTS/PLATES
TO THREADED RODS OR BAR IN TENSION
Posted for public commenting on 6/09/2011 thru 7/07/2011
Note: All comments must be submitted to IAPMO by 7/07/2011
INTERNATIONAL ASSOCIATION OF PLUMBING
AND MECHANICAL OFFICIALS, EVALUATION SERVICES
EVALUATION CRITERIA
FOR
MECHANICALLY ATTACHED ANCHOR NUTS/PLATES
TO THREADED RODS OR BARS IN TENSION
EC 009-2011
1.0 INTRODUCTION
1.1 Purpose: This criteria establishes the requirements for recognition by IAPMO Evaluation Service (IAPMO-ES) of mechanically attached anchor nuts/plates to threaded rods or bars in tension (Manufactured Product) under the 2009 International Building Code® (IBC), the 2009 International Residential Building Code® (IRC), and American Concrete Institute® ACI 318-08. Bases of recognition are section 104.11 of the 2009 International Building Code®, section R104.11 of the 2009 International Residential Code®, and Appendix D of the American Concrete Institute ACI 318-08. The development of this criterion is to provide a guideline for the evaluation of mechanically attached anchor nut/plate to threaded rod or bars in tension, since the IBC, IRC, and associated reference standards do not specify design guidelines for these products.
1.2 Scope: This criteria provides a basis for the testing and evaluation as applicable to the design of a unified or combined anchor nut/plate singular component that is mechanically attached to threaded rods or bars that develop the specified yield and specified tensile strengths tested without concrete.
2.0 REFERENCE STANDARDS
2.1 Standards referenced in this criteria shall be applied consistently with the specific code(s) complied.
2009 IBC International Building Code®
2009 IRC International Residential Code®
ACI 318-08 Building Code Requirements for Structural Concrete,
American Concrete Institute
ASME/ANSI B1.1 Unified Inch Screw Threads, UN & UNR Thread Form
– 2003
ASTM A 36–05 Standard Specification for Carbon Structural Steel, ASTM International.
ASTM A 193-04a, Standard Specification for Alloy-Steel Nuts, ASTM International.
ASTM A 307-04e01 Standard Specification for Carbon Steel Bolts and Studs, 60,000 psi Tensile Strength, ASTM International.
ASTM A 325-04b Standard Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength, ASTM International.
ASTM A 354-03a Standard Specification for Quenched and Tempered Alloy Steel Bolts, Studs, and Other Externally Threaded Fasteners, ASTM International.
ASTM A 370-05 Standard Test Methods and Definitions for Mechanical
Testing of Steel Products, ASTM International.
ASTM A 449-04 Standard Specification for Hex Cap Screws, Bolts and Studs, Steel, Heat Treated, 120/105/90 ksi Minimum Tensile Strength, General Use, ASTM International.
ASTM A 572-07 Standard Specification for High Strength Low-Alloy Columbium-Vanadium Structural Steel, ASTM International.
ASTM A 615-04b Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement, ASTM International.
ASTM A 706-04b Standard Specification for Low Alloy Steel Deformed and Plain Bars for Concrete Reinforcement, ASTM International.
ASTM F1554 - 07a Standard Specification for Anchor Bolts, Steel, 36, 55, and 105-ksi Yield Strength, ASTM International.
PCA ACI 318-08 PCA Notes on ACI 318-08 Building Code Requirements for Structural Concrete with Design Applications, Portland Cement Association
3.0 DEFINITIONS
3.1 Mechanically Attached Anchor Nut/Plate: A singular, unified or combined anchor nut/plate component that is factory internally threaded and attached to threaded rod, studs or reinforced bar with a threaded end per Section 3.5.
3.2 Net Section or Stress Area (Ase) of a threaded rod or bar per ANSI/ASME B1.1:
Where do = nominal rod diameter and nt = number of threads per inch.
3.3 Net Bearing Area of the Anchor: The bearing area of the nut/plate Abrg. The net bearing area of anchor equals the gross area of the anchor nut/plate minus nominal area of the attached threaded rod or bar. The minimum net bearing area of the anchor shall not be less than four times the area of the net section or threaded rod stress area of the bar (4Ase).
3.4 Embedment Depth (hef): effective embedment depth of anchor nut/plate is measured from concrete surface to the bearing contact surface of the outermost edge of the largest anchor nut/plate diameter (or perimeter) portion. Refer to Figure 1. The nut/plate shall not have a section projecting outward more than the overall thickness of the projection.
3.5 Threading: Attachment of the anchor nut/plate to the threaded rod or bar using standard internal threads conforming to ASME/ANSI B1.1.
3.6 Projected Concrete Failure Area of a Single Anchor (ANc): projected concrete failure area of a single anchor or group of anchors, for calculation of strength in tension, in.2, per ACI 318-08 Appendix D Section D.5.2.1.
3.7 Projected Concrete Failure Area of a Single Anchor (ANco): projected concrete failure area of a single anchor for calculation of strength in tension if not limited by edge distance or spacing, in.2, per ACI 318-08 Appendix D Section D.5.2.1.
4.0 BASIC INFORMATION
4.1 General: Each submittal shall include the following information for an evaluation report:
4.1.1 Product Description: Description of anchor nut/plate products shall include dimensions, designations, and material specifications.
4.1.2 Installation Instructions: Installation instructions for the anchor nut/plate shall include product installation requirements and details regarding installation of the product.
4.1.3 Identification: Packaging labels for mechanically attached anchor nuts/plates shall include the manufacturer or a registered trademark, model or name of the product, size, and applicable IAPMO-ES evaluation report number.
4.2 Materials: Threaded rods, bolts, unified nut/plate component, and bars shall conform to the following specifications:
4.2.1 Thread rod and bolts: Mild steel threaded rod shall comply with one of the following ASTM A 36, ASTM A 307, ASTM F 1554 Grade 36. High-strength threaded steel rods shall comply with one of the following, ASTM A193, ASTM A 325, ASTM A 354, ASTM A 449, ASTM A 572, ASTM F 1554 Grade 55 or 105.
4.2.2 Reinforced Bars: shall comply with ASTM A 615-04b or ASTM A 706-04b.
4.2.3 Unified Anchor Nut/Plate Component Material: The material for the unified anchor nut/plate shall be submitted and conform to a recognized material standard (i.e. GB, ASTM, JIS, EN, DIN, BS, ISO etc...).
4.3 Testing Laboratories: Testing laboratories shall comply with the requirements for compliance with the International Accreditation Service (IAS) ISO/IEC standard 17025 or accredited independent agency recognized by the International Laboratory Accreditation or ANSO. Testing at a non-accredited laboratory may be permitted by IAPMO-ES, provided the testing is conducted under the supervision of an accredited laboratory and the supervising laboratory issues the test report.
4.4 Test Reports: Test reports, submitted for approval by IAPMO-ES, shall consist of:
1. A description of the test procedures, test results, observations, tested assemblies, load measurements, and photographs of specimens and typical failures.
2. A description of the test specimens.
5.0 TESTING AND PERFORMANCE REQUIREMENTS
5.1 Anchor Nut/Plate Dimensions
5.1.1 General: The anchor nut/plate attached to the threaded rod or bar shall be produced in such a manner that they are sufficiently rigid to produce uniform bearing without exceeding elastic deformation up to the specified yield strength of the attached threaded rod or bar.
5.2 Tensile Tests: Reports of tensile and cyclic testing shall be conducted in accordance with Section 6.1 of and shall be submitted for verification in compliance with the conditions cited in Section 6.1, 6.1.1, or 6.1.2.
6.0 TEST METHODS
6.1 Tensile Test: Anchorage capacity under cyclic elastic-plastic loading followed by monotonic tension. At least five specimens shall be tested for each bar size, grade, and nut/plate type for which recognition is sought. Samples shall be tested in accordance with ASTM A370. The failure shall be in the threaded rod or bar and not in the threaded connection between the rod or bar and anchor nut/plate. The mechanical anchor nut/plate to rod or bar connection shall sustain stages 1 through 3 of the specified loading program shown in Table 1, without failure.
Table 1: Loading Protocol for Cyclic Tension Tests
Stage / 1 / 2 / 3 / 4Maximum Load / 0.95fy / 2εy / 5εy
Minimum Load / 0.05fy / 0.05fy / 0.05fy / Load in Tension
to Failure
Number of Cycles / 20 / 4 / 4
6.1.1 Acceptance: The tensile strength of the anchor assembly must meet or exceed the minimum specified tensile strength of the attached threaded rod or bar per requirements of Section 5.1.1.
6.1.1.1 Deformation Measurement: Prior to testing, each specimen height shall be measured with an accuracy of 0.004 inch (0.1 mm). After testing, the specimen shall be measured again to verify the specimen has not deformed greater than 0.5% of original height or 0.004 inch taller whichever is greater.
7.0 QUALITY CONTROL
7.1 IAPMO-ES approved inspections of the manufacturing facilities are required for this product.
7.2 Manufacturers’ Quality Assurance System shall comply with the IAPMO-ES Minimum Requirements for Listee’s Quality Assurance System (IAPMO ES-010).
8.0 EVALUATION REPORT RECOGNITION
8.1 Evaluation reports that comply with the above criteria shall include the manufacturer’s name and products name of proprietary components and the description of the material specifications for all assembly components.
8.2 The evaluation report shall also include:
1. Any recommendations for special inspections to be consistent with the requirements of the model code (Section 1704.4 and 1704.13 of the IBC) and as required by IAPMO-ES.
2. Anchorage Design and Calculations in concrete:
a. The anchorage shall be designed in accordance with ACI 318-08 appendix D with Embedment Depth (hef) per Section 3.4 or designed otherwise to the satisfaction of the licensed designs professional and approved by the Building Official.
b. Calculation of projected concrete failure area of a single anchor assembly ANc as defined in Section 3.6 shall state that the maximum outer diameter “d” (or maximum outer diameter of an inscribed circle if the nut/plate has a noncircular shape – diagonal measurement not allowed) of the anchor nut/plate can be included in accordance with Section 3.4 and also state that the ratio of ANc/ANco per ACI 318-08 D5.2.1 can be greater than 1 using the provisions of Section D.5.2.8 and referenced in Figure 1.
Figure 1 - Concrete breakout cone starts at protruding section and outer edge of unified anchor nut/plate.
c. To satisfy minimum concrete cover requirements specified in ACI Section 7.7 the nut/plate is considered part of the bar. For fire resistance cover requirements, refer to Table 721.2.3 of IBC 2009.
d. Special inspections may be required, refer to Section 1704.4, 1704.3, and 1704.15 of the IBC. The inspector’s duties may include verifying grade and size of the reinforcement, product identification and installation.
3. Information specified in Sections 4.1 and 4.2.