DOWNLOAD PDF ARCHITECTURAL FABRIC STRUCTURES

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1 Chapter 1 : Portable Buildings, Fabric Buildings - Sprung Structures Shelter Rite architectural fabric covers the steel frame and provides the weather-resistant features of the structure. The membrane is a heavy reinforced polyester fabric coated with a weather and sunlight-resistant compound. Blackout fabric[ edit ] Blackout material, also known as blockout material, is an opaque fabric. Blackout fabric consists of a laminate that sandwiches an opaque layer between two white exterior layers. Heating and lighting of a structure may be controlled because the fabric does not allow light to permeate the top or walls. Fabric roof in Tulsa, Oklahoma[ edit ] Topcoatings[ edit ] Most fabrics used for fabric structures have some form of topcoating applied to the exterior or coating to make cleaning easier. Topcoating provides a hard surface on the outside of the material, forming a barrier that aids in preventing dirt from sticking to the material, while allowing the fabric to be cleaned with water. As the material ages, the topcoating will eventually erode, exposing the fabric to dirt and making it more difficult to clean. The thicker the topcoating, the longer it will last. However, coatings that are too thick will embrittle and crack when folded. There are several commonly used topcoatings: PVF film lamination is made up of polyvinyl fluoride commercially known as Tedlar. It consists of a film layer laminated to the PVC fabric during the manufacturing process. The result is a thicker fabric that can resist weather and chemical agents better than competing fabrics. Its self-cleaning ability repels such things as acid rain, graffiti, and bird droppings. Because of these characteristics it can often be found in use in industrialized areas, desert regions, and coastal zones. The thicker coating has a slow erosion rate, resulting in a life expectancy of approximately 25 years depending upon environmental conditions. This topcoating is flexible, which creates a strong and consistent bond to the PVC. PVF coated fabrics may be manufactured in a variety of colors, but are also subject to minimum manufacture runs. PVF coating also makes the fabric non-weldable. Seams are not overlapped, but instead are butted with an extra welded seam, then applied to the underside of the fabric that does not have a topcoating. Acrylic topcoating is the most economical and widely available topcoating used. Its spray-on application provides a glossy finish and a resistance to UV degradation. Because the coating is thin, the material is both easy to fabricate and is reparable by high frequency or hot air welding. Depending on environmental conditions, an acrylic topcoating will give the fabric a life span of 10 years or more. Acrylic topcoats are ideal for fabric structures, and can be found on products used as tradeshow pavilions, temporary concert halls, and portable warehouses. PVDF topcoating is composed of a mix of fluorine, carbon, and hydrogen. The combination of the fluorine and carbon provides superior resistance to UV degradation and chemical damage than that of the acrylic topcoat. PVDF coated fabrics also maintain color longer than do those coated with acrylic. PVDF fabrics resist algae and fungi, and also have self-cleaning properties that make them easy to maintain. These coated fabrics are flexible, resist cracking, are easily handled, and generally have a life span of 15 to 20 years depending upon environmental conditions. Because white is the only standard color, other color choices are limited and must be specially manufactured. Because of the chemical properties of the coating, it must be abraded off to expose the PVC before welding. This, too, increases fabrication costs. On site repairs are also difficult, as the membrane must be manually abraded before repair. The finished fabric may be welded without having to abrade the material, which reduces costs. However, because the PVDF is diluted, longevity and the ability to withstand environmental factors are reduced. This results in a general life expectancy of 10 to 15 years. These materials are also available in colors, but are subject to limited manufacturing runs. The effectiveness of TITAN W compared to coatings based on acrylic lacquering and PVDF has been shown by numerous tests on deterioration by atmospheric agents, both accelerated and outdoors weathering test. The result is a coating that gives the fabric the following advantages: Less yellowing and colour variation Longer lasting physical properties Better preservation of flexibility Better self-cleaning properties With these additional advantages, the fabrics coated with TITAN W lacquering will offer better durability compared to the existing coatings used. In addition to the above-mentioned characteristics, fabrics with TITAN W lacquer are high frequency and hot air weldable. Fabric properties[ edit ] When discussing fabric properties for use on a structure, there are several terms that are commonly used: Tensile strength is a Page 1

2 basic indicator of relative strength. It is fundamental for architectural fabrics that function primarily in tension. Tear Strength is important in that if a fabric ruptures in place, it generally will do so by tearing. This can occur when a local stress concentration or local damage results in the failure of one yarn, which thereby increases the stress on remaining yarns. Adhesion strength is a measure of the strength of the bond between the base material and coating or film laminate that protects it. It is useful for evaluating the strength of welded joints for connecting strips of fabric into fabricated assembly. Flame retardancy does not have the same meaning as flameproofing. Fabric that contains a flame-retardant coating can withstand even a very hot point source. However, it can still burn if a large ignition source is present. Free Form Tensile fabric allows one to use free form in building construction as it is flexible material. Structural properties[ edit ] When deciding on a fabric it is imperative to keep certain fabric properties in mind. These include stress versus strain unit load versus unit elongation, expected service life, the mechanisms of joining the material together welding, gluing, etc. Stress versus strain data should be obtained in both uniaxial and biaxial forms. This information characterizes the fabric in terms of stiffness, elasticity, and plasticity. Cost savings to fabric buildings[ edit ] There can be multiple advantages to fabric structures over traditional buildings in certain scenarios. In some cases, no lighting is required as the fabric used is generally translucent, which makes it an energy efficient solution. You can move them, either on wheels or relocate them completely. They cost about half of what a traditional structure costs. When discussing fabric properties for use on a structure, there are several terms that are commonly used: General solar, optical, and thermal performance data Acoustical data. Page 2

3 Chapter 2 : Fabric structure - Wikipedia Fabric Architecture's wide experience in tensile fabric structures including fabric canopies for external and interior projects provides unrivalled design innovation and technical expertise. This test is no longer available for credit Architectural Fabric Structures: The Design Process Designing and building a fabric structure should involve close collaboration among the owner, the designer, the engineer, the manufacturer and the contractor, and should include the input of all parties at the earliest possible stage. Successful fabric architecture requires a strong beginning platform of thoughtful design and qualified engineering that meets intentions for longevity and permanence, in addition to building code requirements and industry standards. Multiple factors must be considered at the outset, including integration of the fabric structure with the site location and the project orientation, as well as its interaction with other site activities and functions. Designers and engineers look at the project holistically and consider an extensive array of criteria, including form, function, economy, material, production, transport and maintenance. The main stages involved in the realization of a typical fabric architecture project are outlined below. A fabric structure begins with an idea, which will determine its form, and its plan, elevations and sections. The idea can be as simple or as intricate as desired. Image courtesy Shade Structures, Inc. The fabric structure begins with an idea, which will determine its form. But what will the structure actually look like? Animation in CAD format can represent the actual final product and is the starting point for converting the concept into reality. Geometry and Structural Analysis. The CAD model is imported into specialty non-linear engineering software which enables analysis that will determine if the structure is stable, whether the membrane is shaped correctly, and if it is over-stressed or in a position to pond. Further, it can provide sufficient information on the sizing and weight of the elements for an accurate cost estimate. Once the required centerline geometry of the structure has been determined, it is modeled in 3D using highly specialized software to define a final equilibrium shape that meets the requirements of the client. The equilibrium shape is then analyzed under various loading conditions to determine the steel, cable and fabric requirements. The fabric requirements are carefully engineered in terms of seam layout and membrane details. This is a test where a small sample of fabric from the roll being utilized for a specific project is tested to ensure it has the assumed industry standard tensile properties. Typically, architectural membranes elongate less than 1 percent over the life of the fabric. When the fabric is received for production, it is in a relaxed state. This compensation factor is applied during the cutting of the fabric to the desired shape. Membrane and Hardware Details. The engineering and analysis process also includes determining the type, size, capacity etc. These membrane details can include items such as fabric corner reinforcements, perimeter cable pockets or cuffs, membrane plates, turnbuckles, clamping and cables, etc. Fabric comes in rolls of certain widths. In order to arrange the patterns in the most efficient way and to avoid unnecessary fabric waste, nesting is necessary. This is a process in which the designed fabric patterns are superimposed on pieces that represent the fabric roll, and the size and orientation are manipulated to achieve the best layout possible. The fabric shape is then patterned. Patterning is the art of representing three-dimensional shapes by connecting a series of flat, two-dimensional templates into one fabric assembly. The size and shape of the panels are determined by engineers using specialized software, and then provided to fabricators who cut and assemble the fabric. Selected to meet the specific project requirements, fabrics have varying degrees of translucency, light reflectivity, UV and weather protection, and non-combustibility. Certain fabrics offer self-cleaning surfaces and all are easily maintained to preserve their appearance and ensure a long life. Strong, durable seams applicable to the individual fabric are critical, and include heat sealing, radio frequency RF sealing and sewn seams utilizing heavy-duty thread, depending on the membrane selected for the structure. Advanced computer controlled cutting technology provides precision load analysis and tight tolerances. Based on fabrication drawings, material is purchased, actually fabricated and packaged for delivery to the site. Some of the more complex projects require installation engineering and input before the construction process begins, and may include things such as specialized hydraulic tensioning components, rigging design and sequencing plans. Steel fabrication should be certified by the International Accreditation Page 3

4 Service IAS board as meeting, or exceeding, the highest standards in the steel fabrication industry. Some steel plants are equipped with state-of-the-art machinery, including robotic welding, computerized roll benders, custom swagers, massive sand blast booths and powder coat ovens and booths, with highly specialized tools and equipment used to cut raw steel and fabricate plates. Photos courtesy of Shade Structures, Inc. The proper components and details are critical to the successful installation of a fabric structure. Load requirements will help determine the type of details and components that are required for support, and whether they are off-the-shelf or custom made. The forms are derived from the bridge building and yacht racing industries, making them both ultra strong and light weight. Several basic forms come into play with fabric structures. A base plate serves as a connection to the ground, wall or the adjacent structural system. It is welded to the bottom of a compression member. Mast or arch structures will require cleats, tabs and gussets, along with struts and bale rings for maximum stability. It is important to note that the membrane plate is one of the most critical components to design and produce. It is the link from the membrane to the structural support and is used to accept the membrane catenary cables. Ease of obtaining a permit will depend on the city and county in which the structure must be installed. Most cities do require a building permit for the shade structures. Quality fabric structures should be fully engineered to meet or exceed the local building code requirements. Typically the turnkey provider will assist in obtaining the necessary documents to obtain a permit. The complexity of the installation depends on the intricacy of the structure and a number of other issues. Some fabric structures do not require permanent foundations and need minimal site preparation. That said, installation is a very important part of the process and essential to the service life and functionality of the fabric structure. The erection procedure must be considered and often takes into consideration site surveys, site preparation, reports on soils and water tables, and weather conditions, particularly wind gusts. Generally they are designed and engineered to meet the wind load requirements of the area in which they are to be used, which normally range from 90 to mph. Site and soil conditions will determine the foundation configuration. Spread footers are used where the soil is unstable and more support is necessary, such as in areas of high water tables, sugar sand, coral rock, or where a soils analysis indicates other unfavorable conditions. By using a pier foundation, the soil friction values can help reduce its size. Spread footings are constructed of concrete and often reinforced with rebar or steel for additional support. Because of their size, they require additional concrete, rebar and dirt removal, and thus spread footings are generally more expensive than other types of foundations. The complexity of the installation depends on the intricacy of the fabric structure. Proper mounting types must also be considered. If these elements are used, anchor bolts are required. It is also advisable to have a plan for unloading materials, installation and tensioning in order to minimize delays and potential problems on site. All this being said, with the many facets and integrated details of a tensile fabric structure, and in order to maximize results and help assure a successful project, an experienced and qualified design-build tension fabric company should be involved in the project from the onset of conceptual design, and should continue to be involved throughout the entire process, including final installation. Fabric Choicesâ Finding the Right Material Architects may want to review the options in terms of several environmental parameters including natural ventilation, reduction in direct sunlight, heat loss or gain, admittance of natural light and contribution to LEED credits. Often the choice of fabric will be climate dependent. For example, in a mixed and hot humid climate, the appropriate approach would encompass rain protection, passive cooling, shading, ventilation, day lighting and reduced heat gain. In snow areas, the slope and snow load of the structure must be considered. Generally speaking, architectural fabrics have a woven substrate that is finished with a coated material. This substrate is what gives fabric its tensile strength. Following are the most popular fabrics on the market today. Teflon coated fiberglass PTFE. This product is a woven fiberglass substrate, and is used for large-scale permanent structures with a required life span of more than 25 years. The Teflon coated material comes to the site as buff in color but bleaches to a milky white over time by exposure to UV rays, typically four to eight weeks. The biggest drawback of the Teflon coated material is its stiffness; the material is brittle and must be handled very carefully to avoid breaking the fibers. Advantages include its longevity, self-cleaning attributes and fire rating. The most recognized and accepted material used for architectural application is Teflon coated fiberglass or PTFE. Photo courtesy of Shade Structures, Inc. PTFE fabrics are used for permanent structures Page 4

5 requiring long life spans. Hence the following costs are presented for general consideration relative to the listed fabrics and for reference only, and should NOT be used for project-specific budgeting without an experienced industry professional. The stated range is based on the fabric area rather than the plan area. Chapter 3 : CE Center - Architecture Extraordinaire: A Primer on Fabric Structures From funnels, arches, towers, and conference walls to video walls and fabric rooms, Formulate Architectural Structures are designed to impress. With plentiful space for branding and messaging, these structures provide an easy way to captivate audiences at trade shows, events and in permanent environments. Chapter 4 : PTFE vs. ETFE Architectural Fabric - FabriTec Structures Eide Industries Inc. is a custom manufacturer of commercial shade structures, awnings, canopies, tension structures, architectural designed structures, industrial sewn canvas products, cabanas, transporter canopies and framed protective covers. Chapter 5 : Tensile Membrane Structures & Fabric Structures FabriTec Structures Architectural Fabric Products We design and build fabric structures across the globe, from iconic architectural fabric structures that define a building, to standard fabric canopies that make a statement. Chapter 6 : SEFAR Architecture TENARA Fabric evolution of fabric structures in architecture in the US and elsewhere, using fabric structures in permanent buildings of increasing size and importance. Chapter 7 : Tensile Fabric Structure Types - Tensile Structure Systems Fabric Structures in Architecture covers the varying ways textiles and their properties are used in building construction, with particular focus given to tensile structures. The text begins with the fundamental principles of textiles, including the origins of fabric architecture, then progressing to a discussion of the modern textiles of today. Chapter 8 : Fabric Architect - Home Fabric Architect (FA) designs and builds custom fabric canopies, awnings, shade structures, carports and architectural fabric structures for people who want "one of a kind" protection from the Elements (rain, wind, snow). Chapter 9 : Architectural Umbrellas - Birdair, Inc. FabriTec Structures builds tensile membrane structures that range vastly in scope and service from massive stadiums and amphitheaters to building entryways and covered walkways. Our core designs include mast supported, arch and frame supported, and point supported fabric structures. Page 5