December 1, 2011 TO: PARTIES INTERESTED IN ALTERNATE DOWEL-TYPE THREADED S SUBJECT: Proposed Revisions to the Acceptance Criteria for Alternate Dowel-type Threaded Fasteners, Subject AC233-1211-R1 (EL/JS) Dear Colleague: We are seeking your comments on proposed revisions to the subject acceptance criteria, as presented in the enclosed draft. These proposed revisions are being posted on the ICC-ES web site for 30 days of public comment. The revisions to AC233 are intended to streamline the criteria and make it easier to use for both applicants and staff. The revisions are being proposed in preparation for updating the criteria to the 2012 International Building Code (IBC) and International Residential Code (IRC), which will be addressed at a future Evaluation Committee hearing. While the proposed revisions appear extensive, they are primarily editorial revisions intended to improve the organization of the document. Specific proposed revisions are described below: 1. Remove the Uniform Building Code (UBC) from the criteria. None of the evaluation reports issued under AC233 reference the UBC. There is no apparent need to continue to address this legacy code. 2. Consolidate the requirements for sample size for connection testing from Section 3.1.4 and various subsections of Section 4.0 into Section 4.2.2. 3. Reorganize Section 3.2 and revise various elements as follows: a. Move the requirements for determining allowable fastener strengths, currently in Section 3.2.3, to Section 3.2.1 and renumber accordingly. b. In Section 3.2.1, add a link to the requirements for bending yield strength testing in Section 3.4.1, to clarify the full scope of fastener strength testing. c. In Section 3.2.2, for testing the tensile strength of the side plate material, reference ASTM A 370 in lieu of ASTM E 8. ASTM A 370 is more commonly referenced in our criteria for tensile testing of steel coupons. This is also the standard referenced in AISI S100. The change to Section 3.2.2 also clarifies that the thickness must be measured. This proposed change is not expected to affect existing report holders, but will improve consistency between ICC-ES acceptance criteria.
AC233-1211-R1 2 d. In Section 3.2.4 (renumbered to Section 3.2.3), clarify that the connection strength being addressed is that of tested connections used to develop the reference design values in the evaluation reports, not the connection strength determined by the engineer of record using the values in the report. Footnotes to the tables in the criteria will be modified to reinforce this understanding. 4. In addition to the proposed revisions to Section 3.3 shown in strikeout/underline format, the section has been broken into paragraphs to make it easier to follow. In the second paragraph, modifications are proposed because the NDS equations used to calculate withdrawal do not include a term for length. The intent is to have the tested withdrawal capacity determined using the same method used to establish the applicable NDS equation. 5. Modify Section 3.4.2 to clarify that if the tests do not confirm the applicability of the calculated values, then the higher safety factor of Section 3.4.3 must be applied to the test values to determine the recognized reference lateral design value. 6. Reorganize the testing requirements to more clearly address the unique requirements for fastener strength testing (Section 4.1) and for connection testing (4.2). 7. Add the required number of test specimens for bending yield strength. A minimum of 10 specimens is proposed, since this reflects the actual minimum number of specimens used by current report holders. 8. Consolidate the requirements of Sections 6.1.1 and 6.2 to better match Table 1. 9. Remove reference to Section 10.1.2 of the NDS from Section 6.3.3 (renumbered to 6.2.3), since it is referenced in Section 6.3.6 (renumbered to 6.2.6). 10. Delete Section 6.3.5 because the application of adjustment factors has been more clearly addressed by Sections 6.3.1 and 6.3.2 (renumbered to 6.2.1 and 6.2.2). One cannot determine which elements govern before applying applicable adjustment factors. Therefore, compliance with this statement is not possible. 11. Add Section 5.3 in response to the Evaluation Committee action on MISC1-0811- R1. 12. Add a condition of use requiring the design of connections using steel side plates to comply with Section 10.2.3 of the NDS, since AC233 does not address qualification of the steel side plates. 13. Other editorial modifications include the following: a. Changing minor diameter or minor thread diameter to root diameter throughout the criteria to better match the NDS and the AF&PA Technical Report 12.
AC233-1211-R1 3 b. Adjustment of Section 1.3 to match the body of the criteria. Please note that ASTM D 5764-97a (2007) is being deleted because it no longer appears in the body of the criteria. c. Adding section headings throughout the criteria. d. Deleting footnote 2 to Tables 3 and 4, since the criteria does not address the 1997 UBC and the 2000 IBC/IRC. Also, actual penetration depth should be accounted for in the reference lateral design values. 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) 423-6587, extension 4315, or Jason Smart, Staff Engineer, at extension 5692. You may also reach us by e-mail at es@icc-es.org. Yours very truly, EL/raf Enclosure cc: Evaluation Committee Elyse G. Levy, S.E. Senior Staff Engineer
Nn www.icc-es.org (800) 423-6587 (562) 699-0543 A Subsidiary of the International Code Council PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ALTERNATE DOWEL-TYPE THREADED S AC233 Proposed December 2011 Previously approved June 2011, June 2010, October 2009, February 2007, October 2006, February 2006, October 2005, June 2005, June 2004 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 104.11 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. NOTE: The Preface for ICC-ES acceptance criteria was revised in July 2011 to reflect changes in policy. Acceptance criteria are developed for use solely by ICC-ES for purpose of issuing ICC-ES evaluation reports.
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ALTERNATE DOWEL-TYPE THREADED S (AC233) 1.0 INTRODUCTION 1.1 Purpose: The purpose of this acceptance criteria is to establish requirements for alternate dowel-type threaded fasteners to be recognized in an ICC Evaluation Service, LLC (ICC-ES), evaluation report under the 2009 and 2006 International Building Code (IBC) and the 2009 and 2006 International Residential Code (IRC), and the 1997 Uniform Building Code (UBC). Bases of recognition are IBC Section 104.11 and IRC Section R104.11. The reason for development of this criteria is to provide guidelines for the evaluation of alternate fasteners, held in place by threaded anchorage in the main member, to those addressed by the code or the code reference, the NDS. 1.2 Scope: This criteria is applicable to alternate dowel-type threaded fasteners used for wood-to-wood or steel-to-wood connections. A fastener is considered an alternate when it has different dimensions than those specified in ANSI B18.2.1 or ANSI B18.6.1, or when it is self-drilling (installed without a lead hole). 1.3 Codes and Referenced Standards: Where standards are referenced in this criteria, the standards shall be applied consistently with the code (IBC or IRC) upon which compliance of the fastener is based. 1.3.1 2009 and 2006 International Building Code (IBC), International Code Council. 1.3.2 2009 and 2006 International Residential Code (IRC), International Code Council. 1.3.3 1997 Uniform Building Code (UBC) AISC 360-05, Specifications for Structural Steel Buildings, American Institute of Steel Construction. 1.3.4 AISI S100-07, North American Specification for the Design of Cold-Formed Steel Structural Members, American Iron and Steel Institute. 1.3.5 AISI (2008) Cold-formed Steel Design Manual, Part VI Test Standards for Use with the 2007 Edition of the North American Specification for the Design of Cold- Formed Steel Structural Members, AISI S904-08, Standard Test Methods for Determining the Tensile and Shear Strength of Screws, American Iron and Steel Institute. 1.3.6 ANSI/AF&PA National Design Specification for Wood Construction (NDS), 2005 edition, American Forest & Paper Association. 1.3.7 ANSI/AF&PA Technical Report 12, General Dowel Equations for Calculating Lateral Connection Values, 1999, American Forest & Paper Association. 1.3.8 ANSI/ASME Standard B18.2.1-1996, Square and Hex Bolts and Screws (Inch Series), American Society of Mechanical Engineers. 1.3.9 ANSI/ASME Standard B18.6.1-1981 (reaffirmed 1997), Wood Screws (Inch Series), American Society of Mechanical Engineers. 1.3.10 ASTM A 370-05, Standard Test Methods and Definitions for Mechanical Testing of Steel Products, ASTM International. 2 1.3.11 ASTM D 1037-06a, Standard Test Methods for Evaluating Properties of Wood-Base Fiber and Particle Panel Materials, ASTM International. 1.3.12 ASTM D 1761-88 (2000)e01, Test Methods for Mechanical Fasteners in Wood, ASTM International; (2006 IBC referenced standard). 1.3.13 ASTM D 1761-06, Test Method for Mechanical Fasteners in Wood, ASTM International (2009 IBC referenced standard). 1.3.14 ASTM D 2395-07a, Standard Test Method for Specific Gravity of Wood and Wood-Based Materials, ASTM International. 1.3.15 ASTM D 2915-03, Standard Practice for Evaluating Allowable Properties for Grades of Structural Lumber, ASTM International. 1.3.16 ASTM D 4442-07, Standard Test Methods for Direct Moisture Content Measurement of Wood and Wood-Base Materials, ASTM International. 1.3.17 ASTM D 4444-08, Standard Test Methods for Use and Calibration of Hand-Held Moisture Meters, ASTM International. 1.3.18 ASTM D 5764-97a (2007), Standard Test Method for Evaluating Dowel-Bearing Strength of Wood and Wood-Based Products, ASTM International. 1.3.19 ASTM E 8-08, Standard Test Methods for Tension Testing of Metallic Materials, ASTM International. 1.3.18 1.3.20 ASTM F 1575-03, Standard Test Method for Determining Bending Yield Moment of Nails, ASTM International. 1.3.19 1.3.21 NASM1312-20 (1997), National Aerospace Standard Practice for Fastener Test Methods, Method 20, Single Shear; Aerospace Industries Association of America, Inc. 2.0 BASIC INFORMATION 2.1 General: The following information shall be submitted: 2.1.1 Product Description: Complete information concerning material specifications (including steel specifications, specified minimum bending yield strength, F yb, etc.), diameters (shank, outside thread and minor root), thread type (cut or rolled), size, and the manufacturing process. This information shall be provided within the submitted quality documentation. 2.1.2 Installation Instructions: Installation details and limitations. The installation details shall be similar to the installation details provided within the submitted test reports. 2.1.3 Packaging and Identification: A description of the method of packaging and field identification of the screws. Where practical with respect to available space on the fastener head, each fastener shall be identified by the manufacturer s identifying mark or logo and the length designation. Each container of fasteners shall have a label noting the evaluation report holder s name and address, the evaluation report number, and the fastener size. 2.2 Testing Laboratories: Testing laboratories shall comply with Section 2.0 of the ICC-ES Acceptance Criteria
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ALTERNATE DOWEL-TYPE THREADED S (AC233) for Test Reports (AC85) and Section 4.2 of the ICC-ES Rules of Procedure for Evaluation Reports. 2.3 Test Reports: Test reports shall comply with AC85. 2.4 Product Sampling: Sampling of the fastener(s) for tests under this criteria shall comply with Section 3.1 of AC85. 3.0 TEST AND PERFORMANCE REQUIREMENTS 3.1 General: Alternate dowel-type threaded fasteners shall be evaluated as described in Section 3.0. Fastener and steel part material specifications shall conform to a national industry standard. Tests shall be performed for each variation of fastener length, thread length, side and main member thickness, steel strength, specific gravity, side and main member orientation, and fastener diameter, unless a pattern of performance and failure mode can be established. 3.1.1 Regression Analysis with Respect to Specific Gravity: Reference design values may be interpolated between tested specific gravity values using a best-fit regression function fitted to tests of connections when all of the following conditions are met: (1) Only specific gravity is allowed to vary in the test series, a minimum of three specific gravity ranges approximately equally spaced are tested, and the average tested specific gravities must be within 10 percent of the respective assigned specific gravities given in NDS Table 11.3.2A. (2) A sufficient number of tests is conducted to result in a coefficient of determination greater than or equal to 0.90, and a percentage standard error of estimate of less than 10 percent. (3) In lateral load testing, a regression line shall pertain to tests exhibiting a common failure mode. Regression analysis shall consider linear, polynomial, exponential, power, and logarithmic functions, and the best fitting function shall be used for the purposes of interpolating reference design values. Regression equations shall not be used for extrapolations to specific gravity ranges greater than or less than the maximum and minimum specific gravity ranges tested. 3.1.2 Wood Members: Reference design values for connections with wood members may be derived for species identified in NDS Table 11.3.2A. Members of target species used in test connections shall have a specific gravity determined on an oven-dry weight and volume basis equal to or lower than the NDS table values, and shall be equilibrated to have a target moisture content complying with Section 4.2.1.3. Testing of specific gravity and moisture content shall be in accordance with Sections 4.14.2.1.2 and 4.2.1.3, respectively. 3.1.3 Applicability of Test Results to Wood with Higher Specific Gravity: Reference design values derived from connection tests may be assigned to like connections with wood species having a higher specific gravity than tested. However, reference design values for connections with wood species exceeding a specific gravity of 0.50 shall be evaluated if predrilled holes meeting the requirements of NDS Section 11.1.4 are not used. 3.1.4 When testing described in Section 4.0 of this criteria requires a 5 percent precision, a 75 percent confidence interval, a minimum of 15 specimens, and a maximum of 40 specimens, there is an implied limit on the 3 COV of 27 percent. If 40 specimens are tested with a COV above 27 percent, the product has failed the test. 3.2 Design of Metal Fasteners and Side Plates: Design of metal fasteners and steel side plates shall comply with Section 10.2.3 of the NDS. The strength of the fasteners shall be qualified in accordance with Sections 3.2.1, the tensile strength of the steel side plates shall be qualified in accordance with 3.2.2, and use of the NDS adjustment factors shall be limited in accordance with Section 3.2.3. 3.2.1 Fastener Strength: Tensile and shear tests shall be performed on each combination of fastener root diameter and fastener steel type in accordance with Section 4.2 4.1.1 of this criteria. The allowable tensile or shear design load of a fastener shall be taken as the average maximum load from the tests divided by a safety factor of 3.0. For fasteners intended for use in lateral load applications, bending yield strength must be determined in accordance with Section 3.4.1. 3.2.2 Side Plates: Standard tensile test specimens of the sheet steel or plate from which the side member is produced shall be made in accordance with ASTM E 8. The thickness and tensile strength, F u, of the steel side plate shall be determined using coupons from the same steel sheet or plate used to make the side member. Tensile testing shall comply with ASTM A 370. 3.2.3 The allowable tensile or shear design load of a fastener shall be taken as the average maximum load from the tests divided by a safety factor of 3.0. 3.2.3 3.2.4 Limits on Use of NDS Adjustment Factors: When the capacity of a tested connection is controlled by fastener or steel side plate metal strength, rather than wood strength, the metal strength resulting reference design value shall not be permitted to be multiplied by the adjustment factors specified in the NDS. 3.3 Reference Withdrawal Design Values: Fastener withdrawal tests shall be performed in accordance with Sections 4.3 4.2.1, 4.2.2 and 4.2.3. The tested reference withdrawal capacity shall be the average maximum test value divided by a factor of 5.0 and divided by the length of the embedded thread. The calculated reference withdrawal capacity shall be the tabulated design value, W, shall be computed using the applicable equations in NDS Section 11.2, where G is taken as the average tested specific gravity and D is taken as the outside thread diameter. When using equation 11.2-1, both the calculated and the tested reference withdrawal capacities capacity shall be determined without including the fastener tip in the embedded thread length. When using equation 11.2-2, both the calculated and the tested capacities capacity shall be determined by include including the fastener tip in the embedded thread length. The recognized reference withdrawal capacity shall be the lesser of the tested or calculated reference withdrawal capacities shall be used. Adjustment factors are permitted to be applied to the reference design value per NDS Table 10.3.1, except as limited by Section 3.2.3. Exception: If the thread geometry of the tested fastener does not conform to NDS Appendix L, ANSI Standard B18.2.1, or ANSI Standard B18.6.1, the tested reference
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ALTERNATE DOWEL-TYPE THREADED S (AC233) withdrawal capacity may be used regardless of the calculated capacity. Adjustment factors are permitted to be applied to the reference design value per NDS Table 10.3.1. 3.4 Reference Lateral Design Values: Lateral load tests shall be performed in accordance with Sections 4.5 4.2.1, 4.2.2 and 4.2.4. Bending yield strength shall be determined in accordance with Section 3.4.1. Reference lateral design values shall be determined in accordance with Section 3.4.2(for a calculated and confirmation testing evaluation approach) or Section 3.4.3 of this criteria. 3.4.1 Bending Yield Strength: Bending yield strength for all fastener diameters and lengths shall be determined by tests in accordance with Section 4.44.1.2. The average bending yield strength of the tested fasteners shall not exceed the specified minimum bending yield strength by more than 10 percent. 3.4.2 Values Determined by Calculation and Confirmed by Testing: This section is applicable to connections where the side plate member is wood, wood structural panel or steel and where the reference lateral design values are determined by calculation and confirmed by testing. The calculated reference lateral design value shall be compared to the tested reference lateral design value. For the purpose of this comparison, the tested reference lateral design value shall be the average ultimate test value divided by 3.2 and reduced by Rs (defined in Section 3.4.4), as applicable. If the tested reference lateral design value is less than the calculated reference lateral design value, the recognized reference lateral design value shall be determined in accordance with Section 3.4.3. The calculated reference lateral design value shall be determined using the yield limit equations found in NDS Section 11.3.1 or by the general dowel equations in AF&PA s Technical Report 12, Table 1, using the following assumptions: 1. The R d term shall be determined in accordance with the NDS. 2. The following fastener diameters shall be used: Equations found in the NDS shall assume a diameter equal to the minor root diameter at the threads. Equations found in Technical Report 12 shall assume a diameter equal to the minor root diameter at the threads except the diameter used to calculate q s in Table 1. This diameter can be either the shank diameter or the minor root diameter at the threads as evaluated. If the shear plane is in the threads, the minor root diameter shall be used. 3. For steel side plate connections, the calculated Mode IV yield value shall be permitted to be used to determine the calculated allowable reference lateral design value, regardless of which yield mode governs the calculation, where provided Mode IV yielding is consistently observed during the test and the steel side plate is at least as thick as the tested steel side plate. 4. For steel side plate connections, the steel dowel bearing strength, F es, shall be permitted to be taken as 2.4F u/1.6 for hot rolled steel plate specified in the Specification for Structural Steel Building (ANSI/AISC 360), or 2.2F u/1.6 for cold-formed steel specified in the North American Specification for the Design of Cold- Formed Steel Structural Members (AISI S100). 5. Wood properties shall be in accordance with the NDS. 6. The dowel bearing length shall be determined per Section 11.3.4 of the NDS. D shall be taken as the shank diameter. The reference lateral design value shall be taken as the lesser of the calculated value or the average ultimate test value divided by 3.2. 3.4.3 Values Determined by Testing: This section is applicable to connections where the side plate member is wood, wood structural panel or steel and where the reference lateral design values are determined solely by testing. The recognized reference lateral design value may exceed the calculated capacity used based on Section 3.4.2 in this criteria, when the reference design value is taken as shall be the average ultimate test value divided by 5.0 and reduced by Rs (defined in Section 3.4.4), as applicable. 3.4.4 Adjustment of Test Values Based on Steel Side Plate Properties: If the yield point of the steel from which the tested steel side plate is formed is larger than the specified value, the test results shall be adjusted downward by a Test values for connections where the side member is a steel plate shall be adjusted to account for the measured tensile strength and thickness of the steel. The adjustment factor, R s, shall be determined from the following equation: where: R s = R s 3.0 2.5 Fu spec t spec Fu tested t tested 1.0 = Steel ratio. (F u spec) = Published ultimate Minimum specified tensile strength of the side plate steel, psi. (F u tested) = Measured ultimate tensile strength of the side plate steel used in the test, psi. (t spec) = Specified minimum side plate thickness, inch. (t tested) = Measured thickness of tested side plate thickness, inch. 3.5 Reference Fastener Pull-through Values: Fastener head pull-through testing shall be conducted in accordance with Sections 4.6 4.2.1, 4.2.2 and 4.2.5. If the fastener is to be used with sheathing, the sheathing types for which recognition is sought shall also be tested for pullthrough. The reference fastener head pull-through design value shall be taken as the ultimate load for each tested configuration, divided by a factor of 5.0. Alternatively, if the fastener has a straight, nontapered shank that extends to an integral washer head, the pull-through design value may be calculated using bearing provisions set forth in Section 3.10 of the NDS. 3.6 Adjustment of Reference Design Values Determination of Wet Service Factor: 4
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ALTERNATE DOWEL-TYPE THREADED S (AC233) 3.6.1 For fasteners intended for connections in wood that is unseasoned or partially seasoned, or for connections that are exposed to wet service conditions in use, wet service factors, C M, for the connections shall be established by comparing the results of withdrawal and lateral fastener tests specified in Sections 4.3 and 4.5 4.2.3 and 4.2.4, respectively, for wet (greater than 25 percent moisture content) versus dry (10 to 14 percent moisture content) wood samples. Where recognition is sought for use in wet service conditions, withdrawal tests shall be performed using fasteners having the minimum thread length and diameter, in wood members having the minimum and maximum specific gravity; and lateral load tests shall be performed using the minimum fastener length and diameter, with wood members of the minimum and maximum specific gravity ranges, and the minimum baseline side member thickness. The wet service factor shall be determined as the ratio of average test values of wet and dry samples for each specific gravity. The wet service factor determined for withdrawal shall also be considered applicable to head pull-through values. In no case shall the wet service factor be greater than what is specified in Table 10.3.3 of the NDS. 3.6.2 3.7 Minimum Spacing, Edge and End Distance: Minimum spacing, end and edge distances in units of length (i.e., inches) shall be derived from the load tests of Section 3.4. Alternatively, confirmatory lateral tests may be run to establish end and edge distance criteria. These tests shall be performed in accordance with Section 3.4 on connection configurations having maximum fastener diameter, minimum baseline side member thickness, minimum main member thickness, and minimum and maximum specific gravity. A comparison of the results from the confirmatory tests (i.e., with minimum end and edge distances) to those of the corresponding configurations tested under Section 3.4 shall indicate that the former are greater than or equal to the latter. In no case shall the spacing, edge and end distances be less than specified in Table C11.4-7 C11.1.4.7 of the NDS Commentary for fasteners with shank diameters less than 0.250 inch, or less than minimum values specified in NDS Tables 11.5.1A through E for fasteners with shank diameters equal to or greater than 0.250 inch. 4.0 TEST METHODS 4.1 General Fastener Strength Tests: 4.1.1 Shear and Tensile Strength: In the immediate vicinity of the location in which the fastener is driven, each wood member shall be free of knots, sloped grain and other growth characteristics that may affect the test results. The specific gravity and wood species of the wood materials shall be determined in accordance with ASTM D 2395. The moisture content of the wood samples shall be determined in accordance with ASTM D 4442 or D 4444 (handheld moisture meters). One sample specific gravity and moisture content calculation shall be provided within the submitted test reports. Tensile and shear tests of fasteners shall be conducted in accordance with AISI S904. Alternatively, shear tests of fasteners may be conducted in accordance with NASM1312-20. A minimum number of samples shall be tested to achieve a precision of 5 percent at 95 percent confidence interval, with a minimum sample size of 10 (refer to ASTM D 2915). 4.1.2 Bending Yield Strength: Wood samples shall be conditioned to reach equilibrium with a moisture 5 content of 10 to 14 percent when testing for dry in-service conditions. When testing for wet in-service conditions, wood samples shall have a moisture content greater than 25 percent. The bending yield strength of fasteners shall be determined in accordance with ASTM F 1575, and the following: 4.1.2.1 The 5 percent diameter bending yield strength shall be defined by the section at the root diameter. 4.1.2.2 The fastener shall be placed on the cylindrical bearing points for testing so that the transition zone between shank and thread is as close as possible to the midpoint between the bearing points, with the load applied at the transition or in the threaded section. 4.1.2.3 The fastener designation, overall length, length of thread, root diameter, and bending yield strengths shall be recorded. 4.1.2.4 A minimum of ten samples shall be tested. 4.2 Fastener Metal Strength: Connection Tests: Tensile and shear tests of fasteners shall be conducted in accordance with AISI S904-08 (Standard Test Methods for Determining the Tensile and Shear Strength of Screws). Alternatively, shear tests of fasteners may be conducted in accordance with NASM1312-20. A minimum number of samples shall be tested to achieve a precision of 5 percent at 95 percent confidence interval, with a minimum sample size of 10 (refer to ASTM D 2915). 4.2.1 Wood Test Member Requirements: 4.2.1.1 Growth Characteristics: In the immediate vicinity of the location in which the fastener is driven, each wood member shall be free of knots, sloped grain and other growth characteristics that may affect the test results. 4.2.1.2 Specific Gravity: The specific gravity of each wood member used in the connection tests shall be determined in accordance with ASTM D 2395, on an ovendry weight and volume basis. One sample specific gravity calculation shall be provided within the submitted test reports. 4.2.1.3 Moisture Content: Wood samples shall be conditioned to reach equilibrium with a moisture content of 10 to 14 percent when testing for dry in-service conditions. When testing for wet in-service conditions, wood samples shall have a moisture content greater than 25 percent. The moisture content of the wood samples shall be determined in accordance with ASTM D 4442 or D 4444 (handheld moisture meters). One sample moisture content calculation shall be provided within the submitted test reports. 4.2.2 Sample Size: A minimum number of samples shall be tested to achieve a precision of 5 percent at a 75 percent confidence interval, with a minimum sample size of 15 specimens and a maximum sample size of 40 specimens. There is an implied limit on the COV of 27 percent. If 40 specimens are tested with a COV above 27 percent, the product has failed the test. Alternatively, a minimum of 10 specimens may be tested, provided a precision of 5 percent at a 95 percent confidence interval is achieved. In this case, there is no limit on the maximum sample size.
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ALTERNATE DOWEL-TYPE THREADED S (AC233) 4.2.3 4.3 Withdrawal Load Test: Fastener pullout strength shall be tested in accordance with ASTM D 1761. Each sample shall have the same embedment length, which shall be equal to the length of the threaded portion of the shank for partially threaded screws and two-thirds of the shank length for screws that are threaded along the entire shank. A minimum number of samples shall be tested to achieve a precision of 5 percent at a 75 percent confidence level, with a minimum sample size of 15 specimens and a maximum sample size of 40 specimens. Alternatively, a minimum of 10 specimens may be tested, provided a precision of 5 percent at a 95 percent confidence level is achieved. 4.4 Bending Yield Strength: The bending yield strength of fasteners shall be determined in accordance with ASTM F 1575, and the following: 4.4.1 The 5 percent diameter bending yield strength shall be defined by the section at the minor thread diameter. 4.4.2 The fastener shall be placed on the cylindrical bearing points for testing so that the transition zone between shank and thread is as close as possible to the midpoint between the bearing points, with the load applied at the transition or in the threaded section. 4.4.3 The fastener designation, overall length, length of thread, minor thread diameter, and bending yield strengths shall be recorded. 4.2.4 4.5 Lateral Load Testing: Lateral resistance and fastener slip shall be tested in accordance with ASTM D 1761, and the following: 4.5.1 1. Friction between the main and side members shall be minimized by the use of a friction-reducing barrier. Alternatively, fasteners shall be inserted to a tightness that permits the wood members of the test assembly to rotate relative to each other with only mild pressure. 4.5.2 The sample size for the lateral load tests shall be sufficient when the tested maximum loads have reached a consistency to achieve a precision of 5 percent at a 75 percent confidence level, with a minimum sample size of 15 specimens and a maximum sample size of 40 specimens. Alternatively, a minimum of 10 specimens may be tested, provided a precision of 5 percent at a 95 percent confidence level is achieved. 4.5.3 2. The failure mode shall be reported for each test. Typical failure modes for lateral load testing include faster withdrawal, head pull-through, side member splitting, bearing failure in the main or side member, and screw fracture. 4.2.5 4.6 Pull-through Test: Fastener head pullthrough capacity shall be tested by means of a test setup in which the fastener installed in the side member is pulled through. Modifications of the test procedure for fastener withdrawal described in ASTM D 1037 may be used. A minimum number of samples shall be tested to achieve a precision of 5 percent at a 75 percent confidence level, with a minimum sample size of 15 specimens and a maximum sample size of 40 specimens. Alternatively, a minimum of 10 specimens may be tested, provided a precision of 5 percent at a 95 percent confidence level is achieved. 5.0 QUALITY CONTROL 5.1 Documentation complying with the ICC-ES Acceptance Criteria for Quality Documentation (AC10) shall be submitted. 5.2 Third-party follow-up inspections are required under this acceptance criteria. 5.3 A qualifying inspection shall be conducted at each manufacturing facility when required by the ICC-ES Acceptance Criteria for Inspections and Inspection Agencies (AC304). 6.0 EVALUATION REPORT RECOGNITION 6.1 The evaluation report shall include tables similar to those shown in this acceptance criteria, as required by Sections 6.1.1 through 6.1.5. Tables shall be prepared by a registered design professional in accordance with Section 4.1 of the ICC-ES Rules of Procedure for Evaluation Reports. 6.1.1 There shall be a table providing fastener specifications dimensions, specified bending yield strength and allowable fastener shear and tension strengths determined in accordance with Section 4.1.1. Refer to Table 1 for an example. 6.1.2 There shall be a table providing reference withdrawal design values (W). Refer to Table 2 for an example. 6.1.3 There shall be a table providing reference lateral design values (Z) for single shear (two-member) connections. Refer to Table 3 for connections consisting of two wood members having identical specific gravity, and Table 4 for connections consisting of one wood member and one steel side plate member. 6.1.4 There shall be a table providing reference fastener head pull-through design values. Refer to Table 5 for an example. EXCEPTION: In cases where it can be demonstrated that withdrawal values will always control for connections having the minimum recognized side member thickness and the maximum thread penetration into the main member, the head pull-through design value table may be omitted from the evaluation report. 6.1.5 There shall be a table providing the minimum fastener end and edge distances and spacing as determined in accordance with Section 3.6.2 3.7. Refer to Table 6 for an example. 6.2 The evaluation report shall include the allowable fastener metal strength determined in accordance with Section 4.2. 6.2 6.3 The evaluation report shall include statements similar to the following, as applicable: 6.2.1 6.3.1 The allowable load for a single-screw connection in which the screw is subject to tension is the least of: (a) the reference withdrawal design value given in Table #, adjusted by all applicable adjustment factors; (b) the reference head pull-through design value given in Table #, adjusted by all applicable adjustment factors; and (c) the allowable screw tension strength given in Table #. 6.2.2 6.3.2 The allowable lateral load for a singlescrew connection is the lesser of: (a) the reference lateral design value given in Table #, adjusted by all applicable 6
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ALTERNATE DOWEL-TYPE THREADED S (AC233) adjustment factors, and (b) the allowable screw shear strength given in Table #. 6.2.3 6.3.3 Connections containing multiple screws must be designed in accordance with Sections 10.1.2, 10.2.2 and 11.6 of the NDS. 6.2.4 6.3.4 Where the screws are subjected to combined lateral and withdrawal loads, connections shall be designed in accordance with Section 11.4.1 of the NDS. 6.2.5 6.3.5 When the capacity of a connection is controlled by fastener or steel side plate metal strength, rather than wood strength, the metal strength is not permitted to be multiplied by the adjustment factors specified in the NDS. Design of connections having steel side plates shall comply with Section 10.2.3 of the NDS. 6.2.6 6.3.6 When designing a connection, the structural members must be checked for load-carrying capacity in accordance with Section 10.1.2 of the NDS, and local stresses within the connection must be checked against Appendix E in the NDS to ensure the capacity of the connection and fastener group. 6.2.7 6.3.7 When use is in structural composite lumber (SCL) products, the minimum fastener end and edge distances and spacing must be in accordance with Table _# of this report or in accordance with the recommendations of the SCL manufacturer, whichever is more restrictive. # TABLE 1 SPECIFICATIONS OVERALL LENGTH 1 LENGTH OF THREAD 2 MINOR THREAD DIAMETER 3 SHANK DIAMETER 3 OUTSIDE THREAD DIAMETER 3 ALLOWABLE STEEL STRENGTH Bending Yield Strength 4, F yb (psi) Tension (pounds) Shear (pounds) For SI: 1 inch = 25.4 mm; 1 psi = 6.9 kpa. 1 For purposes of measuring overall fastener length, countersinking type shall be measured from top of head to bottom of tip. Washer type shall be measured from underside of head to bottom of tip. 2 *Length of thread includes tip. **Length of thread excludes tip. See detailed illustration. 3 Minor thread, shank and outside thread diameters are shown in table with manufacturing tolerances in brackets [ ]. 4 Bending yield strength determined in accordance with ASTM F 1575 using the minor thread diameter. TABLE 1 DIMENSIONS AND STRENGTHS OVERALL LENGTH 1 THREAD LENGTH 2 ROOT DIAMETER SHANK DIAMETER OUTSIDE THREAD DIAMETER BENDING YIELD STRENGTH 3, F yb (psi) ALLOWABLE STEEL STRENGTH Tension (lbf) Shear (lbf) For SI: 1 inch = 25.4 mm; 1 lbf = 4.4 N; 1 psi = 6.9 kpa. 1 For fasteners with countersinking type heads, overall fastener length is measured from top of head to bottom of tip. For fasteners with washer type heads, overall length is measured from underside of head to bottom of tip. 2 *Length of thread includes tip. **Length of thread excludes tip. See detailed illustration. 3 Bending yield strength determined in accordance with ASTM F 1575 using the root diameter. TABLE 2 REFERENCE WITHDRAWAL DESIGN VALUES (W) 1 Tabulated Withdrawal Design Values (W) Are in Pounds per Inch of Thread Penetration into Side Grain of Main Member THREAD LENGTH 2, L For SI: 1 inch = 25.4 mm; 1 lbf/in = 175.13 N/m. W (lbs. lbf/in.) FOR SPECIFIC GRAVITIES OF: 0.67 0.55 0.5 0.46 0.43 0.36 0.31 1 Values shall be multiplied by all applicable adjustment factors (see NDS). (OR if fastener strength controls connection strength:) Values must not be multiplied by any adjustment factors. 2 Reference withdrawal design values are to must be multiplied by the length of thread penetration in the main member. *Length includes tapered tip. **Length excludes tapered tip. 7
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ALTERNATE DOWEL-TYPE THREADED S (AC233) TABLE 3 REFERENCE LATERAL DESIGN VALUES (Z) FOR SINGLE SHEAR (TWO-MEMBER) CONNECTIONS 1 For Sawn Lumber or SCL with Both Members of Identical Specific Gravity SIDE MEMBER THICKNESS, t s For SI: 1 inch = 25.4 mm; 1 lbf = 4.4 N. PENETRATION 2, p REFERENCE LATERAL DESIGN VALUE (Z) FOR SPECIFIC GRAVITIES OF: (pounds lbf) 0.67 0.55 0.5 0.46 0.43 0.36 0.31 Z Z s Z m Z Z Z s Z m Z Z Z s Z m Z Z Z s Z m Z Z Z s Z m Z Z Z s Z m Z Z Z s Z m Z 1 Values shall must be multiplied by all applicable adjustment factors (see NDS). (OR if fastener strength controls connection strength:) Values must not be multiplied by any adjustment factors. 2 For 1997 UBC and 2000 IBC/IRC values: when penetration, p, into the main member is less than 8D (D = shank diameter) the values in the table shall be multiplied by the following penetration depth factor: C d = P/(8D) 1.0. TABLE 4 REFERENCE LATERAL DESIGN VALUES (Z) FOR SINGLE SHEAR (TWO-MEMBER) CONNECTIONS 1, 2 with Steel Side Plate SIDE MEMBER THICKNESS, t s For SI: 1 inch = 25.4 mm; 1 lbf = 4.4 N. PENETRATION 3, p REFERENCE LATERAL DESIGN VALUE (Z) FOR SPECIFIC GRAVITIES OF: (pounds lbf) 3 0.67 0.55 0.5 0.46 0.43 0.36 0.31 Z Z Z Z Z Z Z Z Z Z Z Z Z Z 1 Values shall must be multiplied by all applicable adjustment factors (see NDS). (OR if steel side plate strength or fastener strength controls connection strength:) Values must not be multiplied by any adjustment factors. 2 Minimum steel side plate tensile strength F u = ksi. 3 For 1997 UBC and 2000 IBC/IRC values: when penetration, p, into the main member is less than 8D (D = shank diameter) the values in the table shall be multiplied by the following penetration depth factor: C d = P/(8D) 1.0. MINIMUM SIDE MEMBER THICKNESS TABLE 5 REFERENCE PULL-THROUGH DESIGN VALUES (P) 1, 2 P (lbs. lbf) FOR SPECIFIC GRAVITIES OF: 0.67 0.55 0.5 0.46 0.43 0.36 0.31 For SI: 1 inch = 25.4 mm; 1 lbf = 4.4 N. 1 Values shall be multiplied by all adjustment factors, as applicable to reference withdrawal design values, W, in accordance with the NDS. (OR if fastener strength controls connection strength:) Values must not be multiplied by any adjustment factors. End distance Edge distance Spacing between fasteners in a row Spacing between rows For SI: 1 inch = 25.4 mm. CONDITION TABLE 6 CONNECTION GEOMETRY REQUIREMENTS 1 Loading toward end Loading away from end Loading perpendicular to grain Any load direction Loading parallel to grain Loading perpendicular to grain In-line rows Staggered rows 2 MINIMUM DISTANCE OR SPACING (Fastener Diameter 1) (Fastener Diameter 2) (Fastener Diameter 3) 1 End distances, edge distances and screw spacing must be sufficient to prevent splitting of the wood, or as required by this table, whichever is the more restrictive. 2 Values for spacing between staggered rows apply where screws in adjacent rows are offset by half of the spacing between screws in a row. 8