June 1, 2017 TO: PARTIES INTERESTED IN LOAD BEARING THERMAL BREAK ASSEMBLIES INSTALLED BETWEEN CONCRETE BALCONIES AND CONCRETE FLOORS SUBJECT: Proposed Revisions to the Acceptance Criteria for Load Bearing Thermal Break Assemblies Installed Between Concrete Balconies and Concrete Floors, Subject AC464-0617-R1 (WG/WU) 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. Include expanded polystyrene (EPS) boards as an acceptable Load Bearing Thermal Break Assembly (LBTBA) insulation material along with mineral wool, consistent with the European Assessment Document (EAD) upon which the AC464 Annex 1 Supplemental Assessment Document (SAD) is based. 2. Require EPS boards to be protected by fireblocking conforming with the International Building Code (IBC) Section 718.2.1 to prevent fire propagation from floor to floor. 3. Require that the EPS boards be shown to comply with ICC-ES Acceptance Criteria for Foam Plastic Insulation (AC12). See Section 3.3. 4. Other editorial corrections in Annex 1 - SAD. While the Evaluation Committee will be voting on the revised criteria during the 30- day comment period, we will seriously consider all comments from the public and will pull the criteria back for reconsideration if public comments raise major issues. In that case, we would seek a new committee vote; further revise the draft and post it for a new round of public comments; or put the revised criteria on the agenda for a future Evaluation Committee hearing. 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 and, in memo form,
AC464-0617-R1 2 the responses of our technical staff. 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 3205, or Will Utsey, P.E., Senior Staff Engineer, at extension 5699. You may also reach us by e-mail at es@icc-es.org. Yours very truly, WG/raf Encl. cc: Evaluation Committee William Gould, P.E. Vice President
www.icc-es.org (800) 423-6587 (562) 699-0543 A Subsidiary of the International Code Council PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR LOAD BEARING THERMAL BREAK ASSEMBLIES INSTALLED BETWEEN CONCRETE BALCONIES AND CONCRETE FLOORS AC464 Proposed June 2017 Previously approved October 2015 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. Acceptance criteria are developed for use solely by ICC-ES for purposes of issuing ICC-ES evaluation reports. Copyright 2017 ICC Evaluation Service, LLC. All rights reserved.
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR LOAD BEARING THERMAL BREAK ASSEMBLIES INSTALLED BETWEEN CONCRETE BALCONIES AND CONCRETE FLOORS (AC464) 1.0 INTRODUCTION 1.1 Purpose: The purpose of this acceptance criteria is to establish requirements for load bearing thermal break assemblies installed between concrete balconies and concrete floors to be recognized in an ICC Evaluation Service, LLC (ICC-ES), evaluation report under the 2015 International Building Code (IBC) and the 2015 International Residential Code (IRC). The bases of recognition are IBC Section 104.11 and IRC Section R104.11. The reason for the development of this criteria is to provide guidelines for evaluation of the structural and thermal properties of proprietary load bearing thermal break assemblies, which connect concrete slab balconies with concrete floors. 1.2 Scope: This acceptance criteria applies to proprietary load bearing thermal break assemblies (LBTBAs) consisting of reinforcing steel, stainless steel, mineral wool or expanded polystyrene (EPS) insulation, and proprietary concrete compression shear bearing (CSB) elements. The intended use of the assemblies is to act as a thermal break (minimize thermal bridging) when connecting an external reinforced cast-in-place concrete slab (or balcony concrete slab) to an internal cast-in-place reinforced concrete slab. The connection is also intended to transfer bending moment, or shear forces or a combination of bending moments and shears. Fireblocking is necessary to protect the LBTBA EPS insulation and prevent fire propagation from floor-to-floor. This criteria focus on the structural performance of the load bearing thermal break assemblies and the structural behavior of the interface between the load bearing thermal break assemblies and the connected concrete slabs. The criteria also address thermal break capabilities. The cast-in-place external and internal concrete slabs, to which the load bearing thermal break assemblies are connected, shall be designed and constructed in accordance with the IBC (including ACI 318) and are beyond the scope of this criteria. In addition to the IBC and IRC requirements, this criteria relies on a Supplemental Assessment Document (SAD) identified in Annex 1, attached to this criteria. The requirements in Annex 1 are intended to evaluate the LBTBAs and LBTBA elements through testing and analysis and to provide a means to establish a structural model for the transfer of forces through the LBTBA to the attached concrete slabs. The descriptions and requirements in the attached SAD are part of this criteria, unless noted otherwise in Sections 2 through 4 of this criteria. 1.3 Codes and Referenced Standards: 1.3.1 2015 International Building Code (IBC), International Code Council. 1.3.2 2015 International Residential Code (IRC), International Code Council. 1.3.3 ACI 318-14, Building Code Requirements for Structural Concrete, American Concrete Institute. 1.3.4 ASTM E119-2012A, Standard Test Methods for Fire Tests of Building Construction and Materials, ASTM International. 1.3.5 ASTM C33/C33M-13, Specification for Concrete Aggregates, ASTM International. 1.3.6 ASTM C150-12, Specification for Portland Cement, ASTM International. 1.3.7 European Assessment Document EAD 050001-00-0301, edition September 2014, European Organization for Technical Approvals (EOTA). 1.3.8 Additional applicable reference documents as noted in Section 4 of Annex 1. 1.4 Definitions: 1.4.1 SAD: The Supplemental Assessment Document edited from the referenced EAD described in Section 1.3.7 and attached to this criteria as Annex 1. 1.4.2 Load Bearing Thermal Break Assembly (LBTBA): A product consisting of reinforcing steel, stainless steel, mineral wool or expanded polystyrene (EPS) insulation with fireblocking, and proprietary concrete compression shear block elements, as defined in the SAD. Fireblocking shall conform to IBC Section 718.2.1. 1.4.3 Additional Terms used in the SAD: See Section 1.3 in Annex 1. 2.0 BASIC INFORMATION 2.1 General: The following information shall be submitted: 2.1.1 Product Description: Description of the reinforcement bars, proprietary concrete compression shear block (CSB), mineral wool insulation material, and casing for concrete shear bearing, including product specifications, dimensions, tolerances, manufacturing process, material and mechanical properties. 2.1.2 Installation Instructions: Complete installation instructions for the proper placement of the LBTBAs. 2.1.3 Packaging and Identification: A description of the method of packaging and field identification of the LBTBAs. Identification provisions shall include the evaluation report number. 2.1.4 Field Preparation: Information concerning methods of preparing the LBTBAs and concrete for installation shall be described. 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: Test reports shall comply with AC85 and additional requirements prescribed in the SAD. 2.4 Product Sampling: Sampling of the elements described in Section 2.1.1 of this criteria and the complete load bearing thermal break assemblies, for tests under this criteria shall comply with Section 3.1 of AC85. Page 2 of 3
PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR LOAD BEARING THERMAL BREAK ASSEMBLIES INSTALLED BETWEEN CONCRETE BALCONIES AND CONCRETE FLOORS (AC464) 2.5 Conversion Factors: The evaluation report shall describe appropriate products, such as steel reinforcement provided at the job site, in US customary units consistent with the IBC and the SAD. 3.0 DESIGN, TESTING AND PERFORMANCE REQUIREMENTS 3.1 Design: Design of the exterior and interior concrete slabs, and the connections for transferring of loads between the exterior and interior slabs, through the LBTBA, shall comply with ACI 318. 3.2 Descriptive Information, Testing and Performance Requirements: Descriptive information, testing and performance requirements for the LBTBAs shall comply with Annex 1attached to this criteria. A test plan shall be developed in accordance with Clause 2.2.1 in Annex 1. The testing and analysis shall include consideration, at a minimum, but not limited to, for the following limit states. Bending moment Shear Tension in steel reinforcement Concrete edge failure Bearing resistance 3.3 Expanded Polystyrene (EPS) Insulation Board: EPS boards shall be shown to comply with ICC-ES Acceptance Criteria for Foam Plastic Insulation (AC12). 4.0 QUALITY CONTROL 4.1 The products shall be manufactured under an approved quality control program with inspections by ICC- ES or by a properly accredited inspection agency that has a contractual relationship with ICC-ES. Quality documentation complying with the ICC-ES Acceptance Criteria for Quality Documentation (AC10) and Section 3 in Annex 1 shall be submitted. 5.0 EVALUATION REPORT RECOGNITION The evaluation report shall include the following: 5.1 Product information described in Section 2.1 of this criteria. 5.2 The structural design methodology or specific assembly structural capacities described in Clauses 2.2 4.2 and 2.2.5.2 of Annex 1attached to this criteria. 5.3 Insulation (thermal break) details and information. 5.4 Requirements that job site special inspection shall conform to Sections 1705.1.1 and 1705.3 of the IBC and applicable portions of ACI 318, including specific requirements for the LBTBAs. 5.5 Typical construction details of the LBTBAs. 5.6 A statement that the design and installation of the LBTBAs must be in accordance with the evaluation report and the manufacturer s installation instructions. 5.7 A statement that complete construction documents, including plans and calculations verifying compliance with the evaluation report, must be submitted to the code official for each project at the time of permit application. The construction documents and calculations must be prepared and sealed by a registered design professional. Page 3 of 3
Annex 1 SUPPLEMENTAL ASSESSMENT DOCUMENT (SAD) BASED ON EAD 050001-00-0301 (European Assessment Document) Load bearing thermal break assemblies (LBTBAs) which form a thermal break between concrete balconies and internal floors Proposed June 2017 Previously approved October 2015
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 2 of 27 Table of contents 1 SCOPE OF THE SAD 3 1.1 Description of the construction product 3 1.1.1 General 3 1.1.2 Materials 3 1.1.3 Dimension Limitations 3 1.1.4 Structural model 3 1.2 Information on the intended use of the construction product 5 1.2.1 Intended use 5 1.2.2 General assumptions 5 1.3 Specific terms used in this SAD 6 1.3.1 Materials 6 1.3.2 Symbols 7 1.4 Marking of the product 8 2 ESSENTIAL CHARACTERISTICS AND RELEVANT ASSESSMENT METHODS AND CRITERIA 8 2.1 Essential characteristics of the product 8 2.2 Methods and criteria for assessing the performance of the product in relation to essential characteristics of the product 8 2.2.1 General 8 2.2.2 Load bearing components 9 2.2.4 Load bearing capacity 10 2.2.5 Stiffness and deformation 20 2.2.6 Thermal actions (external slab) 20 2.2.7 Thermal resistance 22 2.2.8 Reaction to fire 22 2.2.9 Resistance to fire 23 2.2.10 Concrete durability 23 2.2.11 Resistance to seismic actions 23 2.3 Criteria for the determination of the product-type(s) 23 3 ASSESSMENT AND VERIFICATION OF CONSTANCY OF PERFORMANCE 24 3.1 System of assessment and verification of constancy of performance 24 3.2 Tasks of the manufacturer 24 4 REFERENCE DOCUMENTS 26 Annex A Identification of the construction product 27 A.1 Means of identification 27
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 3 of 27 1 SCOPE OF THE SAD 1.1 Description of the construction product 1.1.1 General This SAD applies to load bearing thermal break assemblies (LBTBAs) consisting of mineral wool insulation material or expanded polystyrene (EPS) insulation material used with fireblocking, load bearing and ancillary components (such as plastic housing) and includes requirements for testing and design procedures for incorporating the assemblies between concrete slabs, which are designed in accordance with ACI 318. The LBTBA is also referred to in this SAD as the product. 1.1.2 Materials The load bearing components consist of common reinforcing steel, ribbed stainless reinforcing steel, plain stainless steel reinforcement and a proprietary concrete compression shear bearing (CSB). Common reinforcing steel and stainless reinforcing steel components transfer tension, compression or shear forces. The proprietary fiber reinforced concrete compression shear bearing transfers compression and shear forces. The thermal break material is mineral wool or expanded polystyrene (EPS) insulation and is a non-load bearing component. Fireblocking shall conform with IBC Section 718.2.1. 1.1.3 Dimension Limitations The following dimensional limits shall be justified by testing and/ or design provisions of ACI 318. The depth of external and internal slabs shall be h 6.30 inches (h 160 mm). Dimensional limitations for the following components: Compression reinforcement Diameter 0.24 inches 0.79 inches (6 20 mm) Number per meterre n 2/m of assembly Axial edge distance c 1 2 inches (c 1 50 mm) Tension reinforcement Diameter 0.24 inches 0.79 inches (6 20 mm) Number per meterre n 2/m of assembly Axial edge distance c 1 2 inches (c 1 50 mm) Shear force reinforcement Diameter 0.24 inches 0.79 inches (6 20 mm) Number per meterre n 2/m of assembly Axial edge distance c 1 6 inches (mm) Mandrel diameter D 6inches (mm) Inclination 30 α 60 The bends of the shear force reinforcement shall be started at a distance of at least 2 inside the concrete. Concrete compression shear bearing (CSB) Number per meterre n 2/m of assembly Axial edge distance c 1 3.15 inches (c 1 80 mm) 1.1.4 Structural model The structural models given in the Clauses below must be justified by testing and analylsis. The structural models use a strut-and-tie approach. Also included are concrete compression shear bearings with capacities to transfer compression and shear forces.
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 4 of 27 1.1.4.1 Structural model with shear bars The structural model to be applied to transfer forces through the LBTBA and between two concrete slabs is a strut-and-tie model. According to the forces and moments to be transferred by the product, bending and shear, a typical model is shown in Figure 1. Thermal insulationn Section for design Z M l Z Q M r V I V r D Support external slab internal slab Figure 1: Strut-and-tie structure to transfer bending and shear force Schematic example 1.1.4.2 Structural model with concretee compression shear bearing The structural model to be applied to the assembly for the purpose of transferring forces through the assembly and between two concrete slabs is a strut-a and-tie model with a proprietary concrete compression shear bearing (CSB). The concrete compression shear bearing transfers compression and shear forces. According to the forces and moments to be transferred by the product, bending and shear or shear only, two typical models are shown in Figure 3 and Figure 4. Figure 3: Strut-and-tie structure with concrete compression shear bearing (CSB) to transfer bending and shear force Schematic example
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 5 of 27 Figure 4: Strut-and-tie structure with concrete compression shear bearing (CSB) and shear reinforcement to transfer shear force only Schematic example 1.2 Information on the intended use of the construction product 1.2.1 Intended use The intended use of the product is to connect external slabs of reinforced concrete with internal slabs, e.g. floor slabs or walls of reinforced concretee in buildings. The design of external and internal slabs is not part of this evaluation. In particular the product is intended to be used for: minimizing thermal bridges in buildings, transferring static and quasi static bending moments, tension, compression and shear forces. 1.2.2 General assumptions Information regarding issuess such as manufacturing, packaging, transport, storage, maintenance, repair or use which might have an influence on the performances of the product when being installed shall be providedd in the ESR or a document referred to in the ESR. 1.2.2.1 Design and installation of the product Design and installation shall comply with this criteria and the standards and regulations in force at the job site. Instructions for proper installation of the assemblies shall be prepared by the product manufacturer which shall include at least: Orientation of the LBTBA within the slab, Expansion joints within the external slab, Final check of the LBTBA for complete and proper installation. Execution shall follow the indications given in this criteria and SAD and take into consideration the standards and regulations in force at the job site. 1.2.2.2 Packaging, transport, storage of the product Materials shall be handled and stored with care, protected from accidental damage. Bending of reinforcing steel and misalignment of reinforcing steel and compression bearing shall be avoided. On site, the LBTBA shall be stored free from ground, on a rigid, clean surface, to keep them dry and sound.
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 6 of 27 The ESR holder shall provide written instructions related to transportation, storage and handling of the products, in order to avoid damage. It is the responsibility of the ESR holder to ensure that the information on these provisions is given to those who are concerned. 1.3 Specific terms used in this SAD 1.3.1 Materials Insulation material mineral wool thermal break insulation of mineral wool (MW) as defined in the product standard EN 13162 (or ASTM C726), or expanded polystyrene (EPS) as defined in the product standard EN 13163 (or ASTM C578) (to be provided with the assembly) common reinforcing steel reinforcement steel defined in EN 1992-1-1 or deformed reinforcement complying with ACI 318 (to be provided with the assembly or at the job site) stainless reinforcing steel ribbed reinforcing steel made of stainless steel according to EN 10088-1 (to be provided with the assembly) stainless steel stainless steel according to EN 10088-1 (to be provided with the assembly) concrete compression shear bearing, CSB a proprietary element consisting of high strength fiberre reinforced concrete or mortar complying with the manufacturer s specifications, with capacities to transfer compression and shear forces via special shaped load bearing surfaces (to be provided with the assembly). Layers of plastic between concrete of bearing and adjacent slabs are admissible (to be provided with the assembly). compression bearing steel ribbed stainless steel bar (to be provided with the assembly), common reinforcing steel, or stainless reinforcing steel, subjected to compression forces which are transferred to the concrete by bond. concrete of the slabs normal weight concrete having a minimum compressive strength of 3000psi according ACI 318.
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 7 of 27 1.3.2 Symbols The following symbols are used in this SAD and appropriate documents referenced by the criteria and this SAD. angle between axes of shear force reinforcement and the horizontal c linear coefficient of thermal expansion cc coefficient taking account of long term effects on the compressive strength water vapour diffusion resistance factor D thermal conductivity 0 upper limit of strength in fatigue test T temperature difference reduction factor for relevant buckling mode value to determine the reduction factor A wear resistance of concrete compression shear bearing A gt elongation at maximum force A s,nom nominal cross sectional area of the common reinforcing steel bar c 1 axial edge distance CSB concrete compression shear bearing c distance to slab surface D compression bearing, either in steel or in concrete f R relative rib area F lateral force for cyclic displacement test k n factors according to -See Table 6 L 2, L 3 distances to the edges of the thermal insulation material m 28d mass of the specimen at 28 days (after storage under water) m n mass of the specimen after n freeze-thaw cycles M u moment determined in test M t calculated moment M td moment calculated with design strength values of materials n number of components per meterre R e yield strength R e,nom nominal yield strength of the common reinforcing steel bar R m tensile strength R m,nom nominal tensile strength of the common reinforcing steel bar s joint distance of expansion joints t joint thickness of thermal insulation material v h lateral displacement V u shear force determined in test V t calculated shear force V td shear force calculated with design strength values of materials w 1, w 2, w 3 elongation value for vertical displacements w 4 elongation value for horizontal displacements in cyclic displacement test Z tension reinforcement-see Clause 1.1.4 Z Q shear reinforcement-see Clause 1.1.4
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 8 of 27 1.4 Marking of the product Every load bearing thermal insulation assembly shall be clearly identifiable before installation and shall be marked by: Number of the ICC-ES Evaluation Report (ESR), Name or identifying mark of the manufacturer, Name of the assembly as identified in the ESR, 2 ESSENTIAL CHARACTERISTICS AND RELEVANT ASSESSMENT METHODS AND CRITERIA 2.1 Essential characteristics of the product Table 1 shows how the performance of this product is established in relation to the essential characteristics. Table 1 Essential characteristics of the product and methods and criteria for assessing the performance of the product in relation to those essential characteristics Essential characteristic Method of verification and Expression of product No assessment performance (1) (2) (3) (4) Basic Works Requirement 1: Mechanical resistance and stability 1 Load bearing capacity 2.2.4.1 2.2.4.2 2 Stiffness and deformation 2.2.5.1 2.2.5.2 3 Thermal actions (external slab) 2.2.6.1 2.2.6.2 Basic Works Requirement 2: Safety in case of fire 4 Reaction to fire 2.2.8.1 2.2.8.2 5 Resistance to fire 2.2.9.1 2.2.9.2 Basic Works Requirement 3: Safety and accessibility in use 7 Same as for Basic Works Requirement 1 Basic Works Requirement 5: Energy economy and heat retention 9 Thermal break resistance 2.2.7 2.2.7 Basic Works Requirement 6: Protection against seismic actions (TBD) 10 Design for seismic actions 2.2.11.1 2.2.11.2 SAD Basic Works Requirement 7: Sustainable use of natural resources Not specified in this version of SAD. General aspects relating to the performances of the construction product 13 Concrete durability 2.2.10 2.2.10 2.2 Methods and criteria for assessing the performance of the product in relation to essential characteristics of the product 2.2.1 General Verifications according to Clauses 2.2.4 to 2.2.11 shall be accomplished by calculation and/or by large scale tests. A plan shall be submitted to ICC-ES for review prior to commencing testing and analysis. The plan shall consider the following:
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 9 of 27 To establish limit state capacities, testing shall be used unless limit state capacities can be determined by calculations as noted in the remaining part of this Clause 2.2.1. For determination of a limit state capacity of the product, for limit states that are not at the interface between the product and the adjoining concrete slabs, if the limit state capacity can be established by either Euro code or ACI 318, calculations for determination of limit state capacities can be used. For using Euro code equations to determine a limit state capacity, since Euro code uses partial safety factor and characteristic values, justification shall also be submitted verifying the safety index of the limit state, derived by the Euro code, is equal to or exceeds ACI 318 requirements. For determination of limit state capacities related to limit states at the interface between the product and the surrounding concrete slabs, calculations can be used to establish the limit state capacities provided the limit state capacity can be established by ACI 318 and IBC Section 1604.4. Seismic design requirements of the IBC See Section 3.2 in the criteria text for limit states information Drawings shall be submitted where necessary to clarify the intent of the testing. 2.2.2 Load bearing components As noted in this Clause, the material specifications for the components depend on whether the components are part of the LBTBA delivered to the job site or are separate components used at the job site to complete the construction. 2.2.2.1 Common reinforcing steel As common reinforcing steel only ribbed reinforcing steel is used. The nominal yield strength of the common reinforcing steel shall be at least R e,nom 400 MPa (58ksi) and at maximum R e,nom 600 MPa (87ksi). The steel reinforcement is used to transfer tension and compression forces. 2.2.2.1.1 Method of verification Depending on the use-lbtba or job site, the common reinforcing steel shall comply with a specific ASTM standard or be tested according to EN ISO 15630-1 with regard to: Yield strength, Ratio tensile strength to yield strength, Elongation at maximum force, Relative rib area, Bendability, Mass per meterre. 2.2.2.1.2 Method of assessing The common reinforcing steel shall conform to a specific ASTM standard or EN 1992-1-1, Table C.1. The minimum value for yield strength shall be 400 MPa (58ksi). 2.2.2.2 Stainless steel and stainless reinforcing steel The yield strength of the stainless steel and stainless reinforcing steel shall be at least R e 450 MPa (65.3KSI). The stainless steel can be plain bar or ribbed reinforcing steel. The steel reinforcement can be used to transfer tension and compression forces. 2.2.2.2.1 Method of verification Depending on the use-lbtba or job site, the stainless steel and stainless reinforcing steel shall comply with a specific ASTM standard or be tested according to EN ISO 15630-1 with regard to:
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 10 of 27 Yield strength, Ratio tensile strength to yield strength, Elongation at maximum force, Relative rib area, Bendability, Mass per meterre. 2.2.2.2.2 Method of assessing The mechanical properties of the stainless steel and stainless reinforcing steel shall comply with a specific ASTM standard or conform in analogy to EN 1992-1-1, Table C.1. Stainless steel of the minimum strength class S460 shall be used. The minimum value for yield strength of the stainless reinforcing steel shall be 450 MPa (65.3ksi). 2.2.2.3 Concrete compression shear bearing The concrete compression shear bearing is a proprietary suitable shaped element of fiber-reinforced concrete to transfer the compression and shear forces of the load bearing thermal insulation element. The end faces of the element can be provided with a specific geometry and additional components to facilitate movement between the external and internal slab. 2.2.2.3.1 Method of verification The dimensions of the concrete compression shear bearing shall be determined with suitable measurement equipment according to its specification. The compression strength can be determined with prisms used for flexural bending tests according to EN 196-1 (or ASTM C109). For concrete compression shear bearings flexural strength shall be determined with prisms of the concrete according to EN 196-1. 2.2.2.3.2 Method of assessing The tolerances shall meet the specification of the concrete compression shear bearing. The characteristic maximum force and the characteristic compressive and flexural strength of the concrete compression shear bearing shall be declared as a 5 % fractile at a probability of 0.90 (onesided). For evaluation EN 206-1 applies. 2.2.3 Thermal insulation material Thermal insulation products of mineral wool (MW) according to EN 13162 (or ASTM C726) or expanded polystyrene (EPS) according to EN 13163 (or ASTM C578) are used. 2.2.3.1 Plastic cover The function of the plastic cover is to protect the insulation element from damage. The plastic cover does not contribute to the load bearing capacity of the load bearing element. 2.2.4 Load bearing capacity 2.2.4.1 Method of verification 2.2.4.1.1 General Load bearing capacity shall be determined in accordance with Clause 2.2.1. The calculations shall be verified in large scale tests. See Clause 2.2.1 for additional requirements. The assembly of the load bearing thermal insulation element including its dimensions shall be given in drawings. All structural component dimensions shall be identified, including the minimum and maximum of each dimension. The following shall be considered by calculations and or testing: failure of tension bars failure of shear reinforcement or concrete, failure of compression shear bearing, in compression and shear, concrete edge failure.
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 11 of 27 As noted in Clause 2.2.1, a plan shall be submitted for review by ICC-ES prior to commencing any testing. 2.2.4.1.2 Load bearing capacity of the components 2.2.4.1.2.1 Butt welded bars Butt welding one stainless steel bar or stainless reinforcing bar with two common reinforcing steel bars. Job site welding shall comply with the appropriate American Welding Society standards. In case of bars with the same diameter testing according to EN ISO 17660-1 applies. In case of bars with different diameters the load bearing capacity of the welded bars has to be calculated and tested, taking into account the different diameters and the different yield strengths of the common reinforcing steel bars and the stainless steel bar. 5 samples per diameter combination have to be tested and evaluated according to EN ISO 6892-1 and following EN ISO 17660-1. 2.2.4.1.2.2 Buckling test of compression bars The length of the specimen shall result in a free length of at least 2 maximum thickness of the thermal insulation material. The total length of the specimen shall consider the device to hold in place the specimen in the testing machine. The end planes of the specimen shall be flat and square cut. The specimen shall be placed in a testing machine with a device capable to efficiently hold it in place throughout the test. Loading shall be by the head of the testing machine, travelling at a constant speed. Maximum load shall be attained not before 1 minute after the test has started. 5 specimens per size of the compression element shall be tested. The characteristic value as a 5 % fractile of the maximum force shall be declared. 2.2.4.1.3 Large scale tests 2.2.4.1.3.1 General Large scale tests are necessary to verify the load bearing capacity of the LBTBA elements. For products intended to transfer bending moments bending tests shall be performed and for products intended to transfer shear forces only shear tests shall be performed. The tests to be performed are quasi static tests. According to the intended detail of verification, the following tests are required, general or specific verification. 2.2.4.1.3.2 General verification The tests for general verification shall be performed with the maximum intended number of tension reinforcement, shear reinforcement, compression bearings and compression shear bearings and the smallest intended concrete compressive strength. 5 large scale bending tests for products transferring bending and shear 5 large scale shear tests for products transferring shear only 2.2.4.1.3.3 Detailed verification to create a design concept If specific combinations of tension, shear and compression elements require particular failure mode to be examined to verify design concepts or deviations from the configurations for general verification deem it necessary for verification, tests in accordance with Table 2 shall be conducted. Typical examples are the following: Buckling load is determined in testing, Edge distances smaller than determined in Clause 1.1.3, Anchorage or length of lap splice is smaller than required by ACI 318, Change of failure mode from concrete failure of slab to failure of proprietary compression shear bearing.
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 12 of 27 Table 2: Tests for detailed verification to create a deisign concept No Type of Verification Number of tests Remark (1) (2) (3) (4) 1 2 3 5 6 7 Tension reinforcement Shear reinforcement Compression reinforcement 3 3 3 Proprietary concrete compression shear 3 bearings Concrete edge failure of the internal slab 3 Failure of anchorage of tension or shear reinforcement 3+3 3 (+3) 8 Others 3 Steel failure in test or measuring elongation of tension reinforcement and verification of the design concept Steel failure in test or measuring elongation of shear reinforcement and verification of the design concept If the buckling load is verified by calculation or by buckling tests on the compression bearings (see the Clause 2.2.4.1.2.2) this is a reference test to confirm the assumptions. design concept independent on the concrete strength design concept dependent on the concrete strength 3 with minimum specified concrete strength and 3 with maximum specified concrete strength If the anchorage is different from the ACI 318 at least three tests with a minimum specified concrete strength shall be performed. If the design concept of anchorage depends on the concrete strength, three further tests on the specified maximum concrete strength shall be performed. Other differences from the ACI 318 are evidenced by each case of three tests. The applicability of the design concept to other load bearing thermal break assemblies, e.g. assemblies without an offset and assemblies with an offset between external and internal slab, shall be verified by additional testing. A test plan shall be submitted to ICC-ES for review prior to commencingemcing any testing. 2.2.4.1.3.4 Specimen requirements for large scale and quasi-static testing The design of the specimens shall be such that the maximum load per meter (39.4 inches) is tested. The width of the specimen is at least one meterre (39.4 inches) or 5 h whichever is greater. Where h is the thickness of the slab. The specimen shall have the minimum slab thickness of 160 mm (6.3 inches). Due to less rotation in the joint, the test results can be applied to larger slab thicknesses with h <= 500 mm (19.7 inches). However, one specimen with the maximum thickness shall be tested to verify the assumption. The specimen shall in general have the maximum thickness of the thermal insulation material. Due to less rotation in the joint, the test results can be applied to smaller joint thicknesses. The edge distance of the compression bearings to the surface of the slab shall be the minimum value. At least one specimen shall have compression bearing with a minimum axial edge distance. The concrete strength of the specimen shall cover the designated concrete strength class with a tolerance of ± 5 N/mm 2 (725 psi).
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 13 of 27 With f ck,cyl = 0,8 f ck,cube150 The mean values of tested concrete compressive strengths, as defined in ACI 318, shall be used. The results may be interpolated between two concrete strength classes. The age of the test slabs shall be at least 7 days. The concrete mix design shall follow recommendations for proportioning in ACI 318. Proportions may be varied to achieve desired specified compressive strength. No cementitious additives shall be added to the concrete test members. Portland cement shall comply with ASTM C150. Concrete aggregates shall comply with ASTM C33. In order to determine the material properties of the specimens, tests according to Table 3 shall be performed. Reinforcement anchorage and bar splices shall comply with ACI 318. The tensile strength of the concrete slabs shall be determined and compared with the measured values of the concrete compressive strength. If the measured tensile strength is greater than the calculated, more detailed studies are required. Additional information regarding the test procedure such as specific test procedures, test specimen size, support conditions, loading and conditions of acceptance, shall be inclulded in the test plan referenced in Clause 2.2.1. Table 3: Evaluation of material properties Compliance with or equivalency to ACI 318 requirements shall be provided. No Item Specimen Number Testing procedure (1) (2) (3) (4) (5) 1 Compressive strength of the concrete slab at time of testing Cube 150 mm (5.9 inches) or cylinder 160/320 mm (6.3/12.6 inches) 3 EN 12390-3 2 Flexural strength or Tensile splitting strength of the concrete of the slab at time of testing Prism 150/150/700 mm (5.9/5.9/27.6 inches) or Cylinder 150/300 mm (5.9/11.8 inches) 3 EN 12390-5 or EN 12390-6 3 Compressive and flexural Prism 160/40/40 mm strength of concrete compression (6.3/1.57/1.57 inches) shear bearing at time of testing 10 1) EN 196-1 4 Strength characteristics of common reinforcing steel Steel bar 3 EN ISO 6892-1 5 Strength characteristics of stainless steel Steel bar 1) A smaller number is also acceptable for a small scatter of the test results, provided justification is submitted. 3 EN ISO 6892-1 2.2.4.1.3.5 Full scale test rig To consider indirect load transmission, the support of the supported slab shall have a distance (L 3 according to Figures 5 to 8) to the edge of the thermal insulation material of at least the thickness of the slab. The force is applied by a line load. For shear tests the load shall have distance of at least twice the thickness of the slab from the edge of the thermal insulation material. During the test the following measurements and observations shall be performed and recorded:
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 14 of 27 The loads applied, The force in the support of the external slab in shear tests, The absolute displacement at the end of the slab, The relative displacement acrosss the joint, The relative horizontal displacement across the joint in cyclic displacement tests, Optionally strain of the tension bars, Optionally strain of the shear bars, Formation of cracks and crack widths for any load level, The failure mode. However, displacement transducer may be removed before failure to safeguard the integrity of the transducers due to failure of the specimen. The test rig with installed specimen is shown in Figure 5 and Figure 6 for bending tests and in Figure 7 and Figure 8 for shear tests. 2.2.4.1.3.6 Testing procedure The expected load bearing capacity and the serviceability load shall be calculated. The load is applied taxed away (strained controlled). Every load step shall be maintained for at least 3 minutes, this is followed by an unloading, to approximately 1 to 5 kn/ /m (68.5 lbf per foot to 343 lbf per foot), for at least 1 minute. The serviceability load is first applied 10 times, and then the calculated design capacity is applied 3 times. Finally the load is increased until failure of the specimen. Figure 5: Model for bending testing
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 15 of 27 Figure 6: Test rig for bending test Figure 7: Model for shear testing
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 16 of 27 Figure 8: Test rig for shear test 2.2.4.2 Method of assessing 2.2.4.2.1 General A design concept considering all failure modes ( see Clause 2.2.4.1.1) shall be established. This design concept shall be applied to the results of the tests performed as follows. 2.2.4.2.2 Load bearing capacity The load bearing capacities are calculated according to the design concept with the mean values of the strength of the materials, i.e. mean concrete compressivee strength, mean yield strength, etc. The calculated capacities of the slab, M t and V t, are related to the test results, M u and V u, by M M u t and V V u t All tests with the same failure mode are evaluated together by calculating the mean value, the coefficient of variation and the 5 %-fractile. For the evaluation of the tests with concrete edge failure a standardization of the test values is carried out on the actual tensile strength of concrete. The mean value of the calculated concrete tensile strength is the basis for the evaluation with: f ctm f ck, cyl 2 3 N / mm² or f ctm 27. 6 f 2 3 ck, cyl psi (2.9) If the calculation of the bearing capacity of the concrete edge according to the design model is not linearly (with exponent) dependent on the compressive strength of concrete, a conversionn of the compressive strength in the tensile strength of the standardization of the test values is not required. (2.8) M,m m 1 n n i1 M M u t i and V,m m 1 n n i1 V u V t i mean value (2.10)
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 17 of 27 v M 1 n 1 M, m n i1 M M u t i M, m 2 100 coefficient of variation (2.11) v V n 1 1 V, m n i1 V u Vt i V, m 2 100 coefficient of variation (2.12) vm vm M,5% M, m 1 kn and V,5% V, m 1 kn 100 100 5%-fractile (2.13) Where M, m V, m M, 5 % V, 5 % v V, v M mean value of relative moments mean value of relative shear force 5 %-fractile of relative moments 5 %-fractile of relative shear force coefficient of variation of relative moments and shear forces M M u t V u V t k n i i relative moment of test i (2.14) relative shear force of test i (2.15) factors according to EN 1990, Table D.1, for an unknown coefficient of variation For verification of concrete edge failure the coefficient of variation shall be taken according to Table 4. Table 4: Concrete edge failure Coefficient of variation Compliance with or equivalent to ACI 318 requirements shall be provided. No Subject Coefficient of variation v (1) (2) (3) 1 For number of tests < 10 2 For number of tests 10 max{ v according to evaluation of test results 10 % (v according to evaluation of test results) The mean values M, m and V, m and the fractile values M, 5 % and V, 5 % shall be employed to validate the design model. 2.2.4.2.3 Design strength Compliance with or equivalencyecey to ACI 318 requirements shall be provided. The load bearing capacities are calculated according to the design concept with the design values of the strength of the materials. f cd f ² cm cc 4 N / mm design concrete compressive strength of the slab (2.16) c or f f 580 psi cd cm cc c
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 18 of 27 f yd f yk design yield strength of reinforcing steel (2.17) s f cd, CB cc fck, CB c design compressive strength of compression bearing (2.18) Where f cm mean concrete compressive strength of the slab characteristic yield strength of reinforcing steel f yk f ck, CSB cc characteristic concrete compressive strength of the concrete compression shear bearing coefficient taking account of long term effects on the compressive strength, according to Table 5 c partial safety factor for concrete, c = 1,50 s partial safety factor for reinforcing steel, also applicable for ribbed steel passing through the thermal insulation material, s = 1,15 M0 partial safety factor for plain steel, where it passes through the thermal insulation material, M0 = 1,0 2.2.4.2.3.1 Evaluation of concrete failure mode If no tests are performed to notice behavior of concrete edge failure and failure of compression shear bearing the coefficient cc shall be 0.80 (brittle failure according to Table 5). Table 5: cc Additional information shall be provided justifying the factors in Table 5 if no tests are conducted. Compliance with or equivalency to ACI 318 requirements shall be considered in the justification. No Subject cc (1) (2) (3) 1 2 Concrete edge ductile failure brittle failure Concrete compression shear bearing ductile failure brittle failure 1,00 0,80 1,00 0,80 In order to classify the concrete edge failure and/or the failure of compression bearing as a ductile failure, tests are required according to Clause 2.2.4.2.3.1.1. 2.2.4.2.3.1.1 Method of verification Tests according to 2.2.4.1.3 are carried out achieving concrete failure mode of concrete edge or concrete compression shear bearing respectively. After the maximum load is achieved, specimen is unloaded to approximately 1 to 5 kn/m (68.5 lbf per foot to 343 lbf per foot) for at least 1 minute. Ductile behavior is verified if the calculated design capacity can be applied 3 times without significant increase of cracks or damage. At least 3 tests per failure mode are required. 2.2.4.2.3.1.2 Method of assessing 2.2.4.2.2.1.2.1 General A design concept considering all failure modes ( see Clauses 2.2.1 and 2.2.4.1.3) shall be established. This design concept shall be applied to the results of the tests performed as follows. 2.2.4.2.3.1.2. Load bearing capacity The load bearing capacities are calculated according to the design concept with the design values of the strength of the materials. The calculated capacities of the slab, M td and V td, are related to the test results, M u and V u, by
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 19 of 27 M M u td and V V u td (2.19) All tests with the same failure mode are evaluated together by calculating the mean value, the coefficient of variation and the 5 %-fractile. n n 1 M u 1 M d n i M and V u, V d 1 td n i V mean value (2.20), 1 td i i V Md 1 n 1 M, d n i1 M M u td i M, d 2 100 coefficient of variation (2.21) V Vd n 1 1 V, d n i1 V V u td i V, d 2 100 coefficient of variation (2.22) VMd VVd Md,5% M, d 1 kn and Vd,5% V, d 1 kn 100 100 5%-fractile (2.23) Where M, d V, d Md, 5 % Vd, 5 % mean value of relative moments, determined with the design strength of the materials mean value of relative shear force, determined with the design strength of the materials 5 %-fractile of relative moments, determined with the design strength of the materials 5 %-fractile of relative shear force, determined with the design strength of the materials V Vd, V Md coefficient of variation of relative moments and shear forces, determined with the design strength of the materials M M u td relative moment of test i (2.24) i V V k n u td relative shear force of test i (2.25) i factors according to EN 1990, Table D.1, for an unknown coefficient of variation For verification of concrete edge failure the coefficient of variation shall be taken according to Table 6. Table 6: Concrete edge failure Coefficient of variation Compliance with or equivalency to ACI 318 requirements shall be provided. Subject Coefficient of variation v For number of tests < 10 For number of tests 10 max{ v according to evaluation of test results, 10 %} (v according to evaluation of test results)
Supplemental Assessment Document, approved October 2015Proposed June 2017 Page 20 of 27 The partial safety factors are to be taken according to the recommended values of the Eurocodes. Information shall be submitted verifying the partial safety factors are equivalent to the safety factors required by ACI 318. For verification of failure of the compression shear bearings, the coefficient of variation shall be taken from the mean variation of the laboratory tests and an unknown population standard deviation. If they are for the compression shear bearings experience on a large scale for the load capacity and their variations, a known population standard deviation can be recognized. M,5% and V,5% have to be larger than the corresponding partial safety factors given above. The large scale tests shall confirm the applied strut-and-tie model for the product together with the edge distances. 2.2.4.2.4 Extension of results If no particular assessment for specific dimensions or different numbers and combinations of components has been performed, the design concept and results obtained by the tests according to Clause 2.2.4.1.3 can be extended to the following, provided verification by analysis and testing on the upper and lower bounds of parameters that affect the assemblies performance is submitted. Dimensions: smaller thickness of thermal insulation material greater thickness of slab, but not greater than 500 mm (19.7 inches) Tension reinforcement: Diameter smaller nominal diameter than tested number smaller number than tested axial edge distance c1 50 mm (2 inches) Shear force reinforcement: diameter smaller nominal diameter than tested number smaller number than tested axial edge distance c1 6 diameter of mandrel D 6 Compression shear bearing: numbers smaller number than tested axial edge distance c1 80 mm (3.15 inches) distance to the slab surface c larger distance than tested Hence no further testing is required if the limitations above are met, provided verification by analysis and testing on the upper and lower bounds of parameters that affect the assemblies performance is submitted. 2.2.5 Stiffness and deformation 2.2.5.1 Method of verification The tests given in Clause 2.2.4 shall be evaluated for stiffness and deformation. 2.2.5.2 Method of assessing For stiffness, a design concept shall be established and verified with the test results from Clause 2.2.4.1.3 and the evaluation from Clause 2.2.4.2.3. 2.2.6 Thermal actions (external slab) 2.2.6.1 Method of verification The in-plane lateral displacement of the external slab due to temperature changes shall be tested in at least one large scale test with cyclic lateral displacement for each region of nominal diameter for which the minimum width of the joint is to be specified in the evaluation report. Details regarding the test protocol and analysis shall be submitted to ICC-ES for review prior to commencing any testing.