Technical Guide for Tensile Surface Structures- Part 1
The Architects’ Task: “The search for the natural in architecture does not restrict the possibilities; it extends them”
Classification of Materials
The coated textile industry produces a wide range of membranes, differing in strength properties. For PVC coated polyester fabrics, conventional classifications have been derived to assist architects and engineers in the selection of membrane material. Two variations of the types have been accepted-Messe Frankfurt and French Design Guide. Messe Frankfurt is more fabric content dependent (yarn linear density & yarn number, also known as fabric count). The French Design Guide reference is more directly dependent on membrane mass (g/M2) as its index. Both accomplish the goal of categorizing membrane properties for fabric selection in a structure or surface.
Please note that no one fabric exactly fits into any one of these categories. Each category is broad enough to identify the relevant membrane attribute needed in the structure. In this case, it is both weight and strength properties.
Further note- these categories do not specify the actual textile structure (woven or weft inserted warp knit), however the five measured attributes would indicate tensile properties that are characteristically one textile structure versus another.
| TYPE | Type I | Type II | Type III | Type IV | Type V |
| SURFACE WEIGHT (G/M2) |
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| French Design Guide | 720 | 1000 | 1200 | 1400 | 2000 |
| WG Messe Frankfurt | 800 | 900 | 1050 | 1300 | 1450 |
| YARN LINEAR DENSITY (DTEX) |
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| French Design Guide | - | - | - | - | - |
| WG Messe Frankfurt | 1100 | 1100 | 1670 | 1670 | 2200 |
| TENSILE STRENGTH warp/weft (kN/m) |
|||||
| French Design Guide | 60/60 | 84/80 | 110/104 | 120/130 | 160/170 |
| WG Messe Frankfurt | 60/60 | 60/60 | 115/102 | 149/128 | 196/166 |
| TRAPEZOIDAL TEAR TEST warp/weft (N) |
|||||
| French Design Guide | - | - | - | - | - |
| WG Messe Frankfurt | 310/350 | 520/580 | 800/950 | 1100/1400 | 1600/1800 |
| YARN NUMBER warp & weft (yarns/cm) |
|||||
| French Design Guide | - | - | - | - | - |
| WG Messe Frankfurt | 9/9 | 12/12 | 10.5/10.5 | 14/14 | 14/14 |
| TYPE | Type I | Type II | Type III | Type IV | Type V |
| Shelter Rite Products |
|
8028 | 9032 | 9440 |
Under Development |
The five main parameters used in this global standard are weight (g/m2), linear density (dtex), tensile strength (strip tensile @ break), trapezoidal test (resistance to tear), and yarn number (the fabric yarn count in both warp and weft directions).
The table above notates the “Type” category for each Seaman Shelter Rite architectural product. Consult the Technical Library of the website (use the proper unit conversions) for further details of each product. This will steer you to the correct fabric selection for your project. When you’re ready, use our Material Selection Guide to help nail down the details for your project.
Reference- European Design Guide for Tensile Surface Structures (2004); Brian Forster & Marijke Mollaert; TensiNet Publication
