Environmentally influenced self-assembly 

Bio-molecular self-assembly by Skylar Tibbits – exploring the potential for individual elements to self-organise into structures

Nature offers another arena to inspire current buildinpractices: epigenesis.

Epigenesis is the process by whicgrowth is significantly influenced by the environment; it is an additional determinant of growth to genetics.

A straightforward example would be the way that trees grow partly in response to the forces that act on them. A branch joining the trunk is subjected to stress in windy conditions and will grow thicker in the affected areas in response.

Because buildings generally do not yet grow in any sense that is truly comparable to biology, there are verfew existing examples of epigenesis in architecture. On that comes close is the proposal for the Biorock Pavilioby Exploration, based on the technology pioneered by marine biologist Thomas J. Goreau and engineer/ architect Wolf Hilbertz.

This uses electro-deposition in seawater to form accretive mineral structures. An electrical current, low enough to be safe for marine lifeis passed through a steel frame submerged in seawaterresulting in dissolved minerals being deposited on thestructure.

To date, the technology has only been used to restore coral reefs by growing mineral structures onwhich corals can become established and flourish. The Biorock Pavilion is intended to be a smalauditorium that will be grown in seawater and then floated to the surface and transported to an urban location, where it will be a venue for small-scale performances.

Design team member Professor Julian Vincent suggested using strain gauges to determine the amount of current supplied to each member, making the growth process epigenetic. Since the rate of accretion is partly determined by the current, the members that were subjected to greater strain would be the ones that would grow more in response.

The rate of accretion can be as high as 50 mm per year anddepending on the speed of deposition, the compressivstrength can exceed that of reinforced concrete. The minerals continue to be deposited for as long as the current passes through the frame and damaged areas will repair themselves.

Offshore wind turbines could use small amounts of surplus electricity to reinforce their foundations with Biorock, or build reefs that help to restore marine ecosystems.

 

The Biorock Pavilion, which is to be grown in seawater in a way that is comparable to epigenesis

The work of the MIT Self-Assembly Lab has explored ways in which elements can be ‘programmed’ to selfassemble into predetermined forms or self-adapt to particular conditions, often through passive forms of energy, such as ambient heat, vibration or magnetic fields.

They define self-assembly as ‘a process by which disordered parts build an ordered structure through only local interaction’.

The founder of the Lab, Skylar Tibbits, has proposed that one of the most useful applications of this approach would be for construction in extreme environments where it may not be safe or feasible for humans to go.

 

Book reference:

Biomimicry in Architecture by Pawlyn, Michael