Civil Engineering Reference
In-Depth Information
2.1.2.5 Polyethylene
Polyethylene coatings are used for cost effective alternative to more durable coated
fabrics when a shorter lifespan is acceptable such as temporary shelters and ground
sheets. Polyethylene coatings are available in a quite wide range of colours with a
relatively high translucency or with a blackout fabric. They are generally used
combined with polyethylene woven slit weaves and can be welded easily.
2.1.2.6 Synthetic Rubbers
The use of coatings based on synthetic rubbers for architectural fabrics is relatively
restricted due to the cost. Neoprene is one of the most common rubber coatings for
architectural uses thanks to its
flexibility over a wide temperature and the resistance
to corrosion, degradation and abrasion. It is used for high quality in
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atables for
heavy duty applications such as boats and tents.
2.1.2.7 Low E Coatings
Due to the increasing demand of coated fabrics with better thermal performance, the
so-called lowE (low emissivity) coatings are becoming more popular for architectural
fabrics. They are mainly based on the same technology used for insulating glass and
consist of an ultra-thin metallic coating based on
fluorinated tin oxide or thin silver
layer(s). The result is a considerable reduction of the heat losses from the interior.
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2.1.3 Coated Fabrics
Coated fabrics are the result of the combination of the fabric and the coating. The
coating is generally applied on both sides and can be the result of several layers and
materials. The yarns can be combined according to different geometries which lead
to different properties, depending on the
final use. According to the principle used
they can be divided into woven fabrics, knitted fabrics and non-woven fabrics.
Woven textiles are the most used type of fabric for architectural uses; the
structure is based on two types of yarns: the warp and the
fill. The warp yarns are
positioned on a loom and the weft yarns are passed over and under in order to make
cloth. The weaving process can follow different patterns, leading to different aspects
and properties. The most common are the plain weave, the basket weave, the satin
weave and the twill weave. During the weaving process the yarns undergo different
levels of curvature, depending on the pattern adopted, with a consequent reduction
in their tensile resistance.
Knitted fabrics, divided into warp-knit and weft-knit, include several types of
fabrics obtained through the interlocking of loops of yarn rather than interlacing two
