AAMA TIR-A8-2016 Structural Performance of Composite Thermal Barrier Framing Systems.pdf

1、AMERICAN ARCHITECTURAL AAMA TIR-A8-16 Structural Performance of Composite Thermal Barrier Framing Systems MANUFACTURERS ASSOCIATION Copyright by the American Architectural Manufacturers Association (AAMA). This document was purchased for China National Institute of Standardization on Tues Dec 20 201

2、6. It may not be reproduced, republished or distributed in any format without the express written consent of AAMA. 1.0 FOREWORD . 1 2.0 INTRODUCTION . 1 3.0 THERMAL BARRIER MATERIALS 4 4.0 DESIGN GUIDELINES 5 5.0 ENVIRONMENTAL IMPACT 22 6.0 TESTING . 23 7.0 APPENDICES . 33 8.0 ATTACHMENTS . 61 9.0 R

3、EFERENCES 70 AAMA. The Source of Performance Standards, Products Certification and Educational Programs for the Fenestration Industry. All AAMA documents may be ordered at our web site in the “Publications Store”. 2016 American Architectural Manufacturers Association These printed or electronic page

4、s may NOT be reproduced, republished or distributed in any format without the express written consent of the American Architectural Manufacturers Association. This document was developed and maintained by representative members of AAMA as advisory information. AAMA DISCLAIMS ALL WARRANTIES WITH REGA

5、RD TO THIS INFORMATION, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL AAMA BE LIABLE FOR ANY DAMAGES WHATSOEVER FROM THE USE, APPLICATION OR ADAPTATION OF MATERIALS PUBLISHED HEREIN. It is the sole responsibility of the user/purchaser to evaluate the accuracy, co

6、mpleteness or usefulness of any information, opinion, advice or other content published herein. AAMA TIR-A8-16 ORIGINALLY PUBLISHED: 1990 PRECEDING DOCUMENT: TIR-A8-08 PUBLISHED: 9/16 American Architectural Manufacturers Association 1827 Walden Office Square, Suite 550, Schaumburg, IL 60173 PHONE (8

7、47) 303-5664 EMAIL webmasteraamanet.org WEBSITE www.aamanet.org Copyright by the American Architectural Manufacturers Association (AAMA). This document was purchased for China National Institute of Standardization on Tues Dec 20 2016. It may not be reproduced, republished or distributed in any forma

8、t without the express written consent of AAMA.AAMA TIR-A8-16 Page 1 1.0 FOREWORD The worldwide manufacturers of fenestration products have several materials from which to produce their component products. Aluminum is one of the preferred materials of choice. However, because of aluminums high therma

9、l conductivity, improved thermal performance for this material is of prime importance. Many thermal barrier designs, which accomplish this end, have been used or are in use currently. The method used in all cases is to interrupt the continuity of the framing system with the inclusion of a low conduc

10、tance material. This is commonly referred to as a thermal barrier. With a properly designed thermal barrier product, the transfer of the thermal energy through an architectural framing system is reduced. This interruption of energy flow has obvious benefits in substantially reducing the total energy

11、 consumption of the building of which the end product is a part. The thermal barrier will also effectively improve the resistance of the framing members to condensation or frost formation. These thermal barrier systems allow aluminum to provide thermal performance comparable with other framing mater

12、ials. Though there are several thermal barrier systems in use today, the scope of this document will address the composite thermal barrier systems that are the most widely used, as known by this documents authors. Guidelines for these framing systems are offered on cavity design, thermal barrier mat

13、erial, selection, testing manufacturing, fabrication, installation and environmental performance. The intent of this report is to provide the design professional with sufficient information to intelligently evaluate composite thermal barrier systems. 2.0 INTRODUCTION 2.1 The primary units of measure

14、 in this document are metric. The values stated in SI units are to be regarded as the standard. The values given in parentheses are for reference only. 2.2 This document was developed in an open and consensus process a nd is maintained by representative members of AAMA as advisory information. 2.3 D

15、efinition of Framing with a Structural Thermal Barrier An aluminum composite framing member consisting of an interior and exterior extruded aluminum section. The two sections are joined by a structural thermal barrier material to improve the thermal performance of the composite section. FIGURE 1 Typ

16、ical Poured and Debridged Thermal Barrier Aluminum Extrusion 2.3.1 Definition of Poured and Debridged Design An aluminum composite framing member, consisting of single extruded aluminum sections separated by a thermoset material providing a structural thermal barrier. The thermoset material is poure

17、d into the cavity of the extrusion. After curing, the extruded bridge is removed. The resultant framing member is a composite member consisting of interior and exterior aluminum sections separated by a structural, insulating thermal barrier. (See Figures 1, 2a and 2b). Copyright by the American Arch

18、itectural Manufacturers Association (AAMA). This document was purchased for China National Institute of Standardization on Tues Dec 20 2016. It may not be reproduced, republished or distributed in any format without the express written consent of AAMA.AAMA TIR-A8-16 Page 2 FIGURE 2a: Typical Poured

19、and Debridged Single Cavity Thermal Barrier Composite Profile FIGURE 2b: Typical Poured and Debridged Dual Cavity Thermal Barrier Composite Profile 2.3.2 Definition of Mechanically Locked Design An aluminum composite framing member, consisting of individual interior and exterior extruded aluminum se

20、ctions separated by a preformed thermal barrier. First, both the interior and exterior aluminum extrusions are knurled. The structural thermal barrier material is then inserted into the knurled extruded cavity of both the interior and exterior portions and after rolling (crimping) the mechanical loc

21、king process is complete. (See Figures 3 and 4). FIGURE 3: Typical Mechanically Crimped In Place Thermal Barrier Extrusions Copyright by the American Architectural Manufacturers Association (AAMA). This document was purchased for China National Institute of Standardization on Tues Dec 20 2016. It ma

22、y not be reproduced, republished or distributed in any format without the express written consent of AAMA.AAMA TIR-A8-16 Page 3 FIGURE 4: Typical Mechanically Crimped In Place Thermal Barrier Composite Section 2.4 History Throughout the world, aluminum extrusions have become the preferred constructi

23、on material for windows and doors. The reasons for the popularity of aluminum are many. Aluminum extrusions are lightweight with one of the highest strength to weight ratios of any material. For the designer, they offer an unlimited variety of shapes. They are produced at close dimensional tolerance

24、s, providing for excellent operational fit and structural stability. Aluminum is not subject to warping, rust or vermin damage. Aluminum accepts many finishes allowing for a wide variety of color applications. Aluminum is the most recycled material used for framing. However aluminum is one of the mo

25、st thermally conductive metals. This high thermal conductance has been a cause of concern related to the use of aluminum in fenestration products, principally energy loss and associated condensation. In response to these concerns, designers have devised methods to separate the exterior metal surface

26、s from the interior metal surfaces, thus greatly reducing the heat and cold transfer. These techniques generally incorporated some type of insulating medium with structural properties. 2.4.1 History of Poured and Debridged Thermal Barriers In 1962, the Soule Steel Company of San Francisco announced

27、a “new method of insulating aluminum windows and curtain-wall systems, which eliminates internal frost build-up in cold climates and is up to 50 percent cheaper than former, less efficient techniques.“ Soule called this system Artic Wall. This development was an important milestone, because the Soul

28、e technique resulted in the first window product to be produced economically with excellent control of dimensional tolerance. The first notable application of this technology which later became known as poured and debridged was for windows and curtain-walls in the construction of the State Office Bu

29、ilding in Fairbanks, Alaska, in 1962. 2.4.2 History of Mechanically Locking Thermal Barriers The mechanical locking thermal barrier system originated in Europe in the early 1970s, by Ensinger GmbH and Wicona, in order to meet the needs of a specific project, developed the structural thermal barrier

30、system. The first known installation of a mechanical locking thermal barrier was in 1978. The first usage in the United States came a little over ten years later, in the spring of 1991. The thermal barrier was used in the Jackson County Public Hospital. It was the first use of a mechanical locking t

31、hermal barrier that had been produced in the United States. These windows went into service in the spring of 1991 and are still in service as of the date of this printing. Along with the advancements in insulating glass, improved sealants, weather stripping and high performance finishes, thermal bar

32、riers have provided a great impetus for the growth of aluminum as the preferred material for architectural framing. Since the early seventies, thermal barriers have achieved such universal acceptance that they are now considered a standard way to produce energy efficient fenestration framing product

33、s. To ensure continued reliability and technical improvements of thermal barriers, AAMA organized the Thermal Barrier Structural Task Group at its October 1981 Annual Meeting. This committee was comprised of experts in the field, including design engineers, process engineers, corporate and marketing

34、 managers and chemists. It was decided at this meeting that the main responsibility of the task group would be to prepare a Technical Information Report (TIR) for the manufacturers of windows, doors, curtain walls, storefronts, skylights and other glazed architectural products that would establish g

35、uidelines, performance standards, processing recommendations and test methods for thermal barriers. Copyright by the American Architectural Manufacturers Association (AAMA). This document was purchased for China National Institute of Standardization on Tues Dec 20 2016. It may not be reproduced, rep

36、ublished or distributed in any format without the express written consent of AAMA.AAMA TIR-A8-16 Page 4 Given the significant innovations and changes in thermal barrier design, AAMA charged the Thermal Barrier Task Group to update the current TIR-A8-90. The mission of the Task Group was to revise an

37、d expand the TIR-A8-90 document to include innovations in products and testing. This document is the result of that effort. 2.5 Effect on Condensation Resistance Factor (Crf) and Thermal Transmittance (U-factor) The thermal barrier serves to isolate the aluminum on the exterior of the framing system

38、 from the aluminum on the interior. A properly designed system will still maintain the structural integrity of the framing while not permitting a thermal short circuit between exterior and interior metal. A thermal barrier provides an effective method of limiting the formation of condensation and fr

39、ost on the interior frame. Condensation at this point can damage interior trim and wall covering or at the very least be a nuisance to the building owner. The ability of a framing system to resist condensation formation is expressed by the Condensation Resistance Factor (CRF). AAMA document 1503, “V

40、oluntary Test Method for Thermal Transmittance and Condensation Resistance of Windows, Doors and Glazed Wall Systems” provides guidance to the design professional on determining the proper Condensation Resistance Factor requirements for a project. In general, framing systems with thermal barriers ha

41、ve significantly better condensation resistance than those without. Like CRF, the coefficient of thermal transmittance (U-factor) for the glazed framing system will also improve when thermally broken sections are utilized. The thermal barrier effectively reduces the amount of heat transfer from one

42、side of the extrusion to the other. The effect of thermal sections on the U-factor of the composite glazed product will depend upon the ratio of the metal area to the glass area. 3.0 THERMAL BARRIER MATERIALS Any material that improves the thermal performance of an aluminum window frame without comp

43、romising the structural integrity of the window may be used as a thermal barrier. All products used for thermal barrier applications must have a set of minimum performance properties. Properties such as tensile strength, elongation, impact resistance, thermal conductivity, flexural modulus, adhesion

44、 properties and heat deflection temperatures should all be considered during the design and application stage. After reviewing all of the technical data, a product that meets the general product parameters should be selected and then run under typical plant conditions in extrusions designed for the

45、particular application. Samples of these extrusions should then be tested to confirm that the product will perform to the expected level. Regardless of the type of thermal barrier product or material chosen, care must be taken in its design and application as the performance properties needed for ea

46、ch application can vary significantly. The manufacturer should be consulted throughout all aspects of this process. This remains the key to the success of any product chosen. It is important to note that an excellent material will not perform in a poorly designed thermal barrier cavity, nor will a p

47、oor material perform in a properly designed cavity. Both the cavity design and the material must be correct. In this specification we will discuss two thermal barrier materials, one being a poured urethane (a mix of two components, used in a poured-and-debridged system) and the other being a preform

48、ed, engineered profile extruded into a thermal barrier shape. There are other materials that may be used as composite thermal barrier materials but they will not be discussed here in detail; however the analytical procedures in this document would still be applicable. The final thermally separated c

49、omposite extrusion must exhibit the following properties: 1. Resistance to deflection must be adequate to meet the requirements of the intended application at the anticipated loads and ambient conditions. 2. Resistance to torsion must be greater than the expected forces caused by the loads on the frame. 3. Resistance to shear must be greater than the expected forces caused by the differences in inside and outside temperatures, weight of the glazing material and structural composite action of the assembly. 4. Resistance to wind loading must be adequate to withstand the continuous pump