Triaxial weaving produces material which is structurally superior to many
sorts of rectangular weaving. Since the structural elements run in three
directions, the resulting fabric is much more resistant to shearing forces
and doesn't easily crimp.
History
Triaxial weaving is part of the traditional craft of basketry. Its use has
been dated back to around 5,700 BC in Japan. For details about that, see [here].
Video
Here are some of the most common types of triaxial weaving:
Sparse triaxial weave
This fabric is sparse. It typically has about half as many structural
elements per unit area - when compared with a rectangular woven fabric made
using the same elements.
One of the feature of this fabric that it has holes in it. While this makes it
unsuitable for some applications, it does help with
applications which require holes or ventilation - such as chair fabric, linen
baskets and lightshades.
Alternatively, it is appropriate where a light material is required -
that is still very strong.
In Japan, this pattern is known as Mutume (six knitting).
This fabric is often known as the basic triaxial weave.
This sort of weave is one of the lightest simple weaves known. Its relative
density (compared with the density of a single flat sheet) is about 1.00.
Sparse triaxial weave
Here is a rendering of this fabric made using bamboo strips.
Dense triaxial weave
This fabric has three layers of material at any point. It is thus stronger
than a rectangular woven fabric made using the same elements. It is very
regular and isotropic.
Its relative density is 3.00. It looks much the same from behind.
In Japan, this pattern is known as Tessen (wire knitting).
Unfortunately, this fabric is relatively difficult to manufacture.
It can be thought of as three "sparse" triaxial weaves interwoven.
For more details, see the page of experiments.
Dense triaxial weave
Here is a rendering of this fabric made using bamboo strips.
Herringbone triaxial weave
This sort of triaxial weaving is not isotropic - but it is fairly common -
perhaps as a result of being relatively simple to manufacture.
This pattern is based on an ordinary biaxial weave. Its relative density is
2.0. It looks much the same from behind.
In Japan, patterns like this one are known as Asanoha (crushed hemp knitting).
This is one of the triaxial fabrics can be constructed with different angles
betwee the fibres. For an example of that, see the
page of experiments.
It would be nice if there was a more isotropic version of this fabric.
I have a separate page about my efforts to locate such a fabric here.
Herringbone triaxial weave
Here is a rendering of this fabric made using bamboo strips.
Medium triaxial weave
This sort of triaxial weaving can be thought of as being composed of two
mirror versions of the basic sparse fabric, interwoven with each other. Its
relative density is 2.0. It looks much the same from behind.
Medium triaxial weave
Here is a rendering of this fabric made using bamboo strips.
3D structures
Triaxial weaving can be used to make curved surfaces in three dimensions. The
locked intersections and the resistance to shearing forces helps to keep the
resulting structires rigid. Fabrics with C6 symmetry can be used -
including the main sparse, medium and dense weaves. The hexagonal geometry
lends itself to hexagon and pentagon constructions - using a similar geometry
to that used in geodesic spheres.
Sparse triaxial woven sphere
Medium triaxial woven sphere
Sparse triaxial woven sphere
These computer-generated sphere images were constructed using AntiPrism and Springie
Sepak Takraw ball (dense triaxial woven sphere)
This shows a traditional woven sphere - used in playing ball games in the
east.
Removing elements
Variations can often be constructed by regularly removing elements.
Sparse herringbone triaxial weave
This fabric is based on the Herringbone triaxial weave. Alternate
white elements have been removed.
Using colour
Dense triaxial weave (Star of David)
Dense triaxial weaving patterns allow for some pleasing aesthetic variations.
Here is a "Star of David" pattern - created by using a third of the woven elements
of a different colour to the rest.
Surface effects
Chequerboard triaxial weave
This pattern is similar to the second herringbone pattern - however, the twill
arrangment is slightly different - and the yellow fibres spend most of their
time near the top of the pattern. The result looks a little like the
dense triaxial weaving pattern - though in this case, the yellow rhombuses are
as numerous as the red and blue ones combined. The pattern resembles a
chequerboard - hence the name
This fabric is not very symmetrical. However, it does have some pleasing
aesthetic properties.
This pattern is based on a 2,2 twill pattern. Its relative density is 3.00.
The front and back of this fabric look quite different - the yellow fibres are
almost invisible from the back. If you want to add a second layer of
fibres in one direction to a dense fabric, using this fabric with yellow
fibres on both sides may be a good way of doing that.
Triaxial fabrics often have good strain resistance, planar shear resistance,
tear resistance, abrasion resistance and bursting resistance. For details, see
the page about properties.
Applications
What applications are suitable for using triaxial techniques?
The main selling points of triaxial weaving are:
Light weight;
Low material cost;
Isotropy;
Shear-resistance.
These are desirable traits for many applications.
In particular, light shades, basketware, hats and high-performance applications
demanding isotropic strain resistance seem particularly attractive
applications for this sort of weaving.
Construction
Sparse triaxial weaving uses three sets of parallel fibres, known as the
warp, the whug and the weft.
The whug is not present in conventional rectangular weaving. During
construction it acts very much like a second warp.
The warp can be laid down in simple parallel lines. The whug is then
laid down on top of it - again in simple parallel l ines.
Finally the weft is woven in and out of both layers - to create the final
fabric.
Patents
Triaxial fabrics - and their production methods - have been the subject of
many patents. We maintain a list of some of them
here.