This experiment shows how microorganisms might help create unconventional composite materials for structural systems.
But what about new and unconventional building materials made with textiles, developed with the help of bacteria? London-based architect and designer Bastian Beyer of the Royal College of Art, in collaboration with designer Daniel Suarez of University of the Arts Berlin, created this self-supporting column out of knitted textile fibres, which was solidified with sporosarcina pasteurii bacteria to form a rigid layer of calcite:
As Beyer explains:
The material offers an alternative to petrochemically derived composite materials as it is based on natural fibres and solidified by a natural process. While it can't structurally compete with high tech fibres such as carbon or glass fibres it offers a novel, sustainable and bio-derived composite with an inherent new aesthetic and characteristics for architectural design. [..] Knitted textile systems allow for much more complex shapes which can be applied as for example spatial dividers, shading features, reinforcement and potentially even structural roof or wall systems.
The process to create the 62-inch (160-centimetre) tall column involved three main steps: first, a design was worked out on a computer in terms of its geometrical and structural layout, as well as the patterning on the form itself (the column includes four different knitting patterns). Second, a human craftsperson then created the forms by hand, using jute and polyester fibres on a custom-designed circular hand-loom.
The third and final step consisted of putting the knitted column in a rotating "bioreactor," where it was then sprayed with an active solution of the sporosarcina pasteurii bacteria. A secondary irrigation system was then utilized to spray a solution of calcium chloride and urea to catalyze the calcification process, which hardens the whole object. For this particular project, the process took about three days of eight successive spraying sessions to bond all the fibres together, in order to get the right level of load-bearing hardness.
The idea was to take advantage of naturally occuring "textile microbiomes," says Beyer:
A textile microbiome is a community of microorganisms inhabiting a specific fibrous substratum. Generally, almost every textile material is inhabited by a distinct microbiome as fibres offer, due to their increased surface area and moisture content, a suitable environment. These microbiomes are in constant (biological) exchange with their environment which varies in their activity depending on external and internal conditions. By utilizing this property of textiles to "host" specific microbiomes and designing a distinct tailored textile microbiome whose activity and reactiveness can be determined and controlled, novel bio-active and responsive composites can be generated.
During the development process, Beyer experimented with various knitting patterns and fibre densities to see how they might affect the bio-calcification process. Having garnered an Autodesk/ACADIA Emergent Research Award, the project was undertaken as part of a larger research project called ArcInTex, with support from Eurecat and Soletanche Bachy.
Ultimately, the goal here is to explore how microorganisms can alter the structural properties of these unconventional building materials -- possibly paving the way for new, high-performing self-assembling or self-repairing materials in the future. To see more, visit Bastian Beyer and Instagram.