What is a helical structure?
A helical structure demonstrates the form of a helix or spiral. A helix is a three-dimensional shape like a wire wound uniformly in a single layer around a cylinder (imagine a spring) or a cone (imagine a corkscrew or spiral staircase).
The helix is an important form in biology, the DNA molecule is known for its two intertwined helices, and many proteins consist of helical molecules.
Helical structures in biology
Helical structures in textiles
Helical structures appear in textiles primarily via the act of twisting or braiding:
the condition of a yarn or similar structure when the component elements have a helical disposition such as results, for instance, from relative rotations of the yarn ends.
Spun yarns are produced by twisting or spinning drawn staple fibres into long threads known as singles, these singles can be further twisted together to form ply yarns. During twisting, the fibres on yarn surface take a roughly helical configuration around the yarn. Staple fibres are held together in a spun yarn by a force called friction.
Friction is the resistance created when one surface or object moves (or rubs) over another.
BRAIDING or PLAITING
the process of interlacing three or more threads in such a way that they cross one another in diagonal formation. Flat, tubular or solid constructions can be formed in this way.
Helical structures aid
Consider the Glass Sea Sponge…
The Euplectella aspergillum (Venus’ flower basket) is a type of glass sea sponge that inhabits the Pacific Ocean at depths that range between 40-5,000 meters. This remarkable creature is primarily made of fine glass, which is a brittle material that crumbles easily, like chalk.
Rather than make itself strong by forming a solid glass structure the sea sponge uses spiral shaped ribs or filaments that form a hollow cage which can withstand crushing pressures (500 atmospheres - 1 atmosphere is roughly 6kg per square inch).
This is because of the cleverly designed helical structure in which the filaments are arranged not just vertically and horizontally but also diagonally. This helical design forms a dense net that prevent the structure from collapsing under pressure and twisting from the deep-water currents.