Earthworks and building foundations symbolically and physically anchor
buildings to their location. Whether buildings seem to grow from their context
or float over their sites, local ground conditions and bearing capacity dictate
the manner in which a building’s vertical loads are transmitted to some type of
footing. Akin to the manner in which a snowshoe spreads a person’s weight
onto a larger surface area, building foundations and footings distribute loads
onto a larger footprint. Foundations require soil that is stable enough to
support loads and that it remains so, in order to keep the building standing
throughout its life.
Traditionally concrete, stone or in some cases carbonized or treated
timber, were used to affix a building into position. Rot resistant materials
such as concrete and stone are more commonly employed as foundations are
susceptible to water infiltration, frost heaving, or soil instability.
Recently, insulated concrete formwork is integrating conventional construction
as the formwork reduces waste while increasing the wall’s thermal performance.
As ecosystems become increasingly fragile, researchers are developing
innovative ways to improve foundation strategies. Rising flood plains, melting
permafrost, sinking water tables are just some of the issues pressuring traditional
monolithic foundations. A research group lead by architect Dr. Martyn Dade-Robertson from Newcastle University
is proposing a type of bacteria to reinforce soil weaknesses by creating a type
of bio-concrete, which could respond to changing conditions over time adjusting
support structures as needed.
Before integrating this type of self-adapting soil becomes common,
lightweight, multipoint, space frame and modular structures are also being used
in fragile conditions to reform standard concrete foundations and
footings. Platforms are built from triangulated structures onto which
buildings are attached as a structure to a large raft. Triodetic structures, a Canadian
firm well known for their space frame assemblies, has begun marketing and
employing this type of raft foundation for a diversity of applications. Space
frame foundations can be tailored to different sites. Buildings can sit lightly
on fragile soils reducing local soil disturbance. Assembled from steel tubes
and connectors, this type of foundation could conceivably be adjusted to
changing conditions over time. Further this type of dry assembly of
prefabricated components allows the structure to be dismounted and redeployed
in other conditions.
Multi-Point foundation system by Triodetic |
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