Environmental Engineering Reference
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the latter. That's MIT scientist Tom Knight once wrote that those differences could
be illustrated by the following example ''A biologist goes into the lab, studies a
system and finds that it is far more complex than anyone suspected. He's delighted,
he can spend a lot of time exploring that complexity and writing papers about it.
An engineer goes into the lab and makes the same finding. His response is: 'How
can I get rid of this?''' Meaning that contrary to biologists engineers excel at
eliminating irrelevant complexity in order to build something that works and is
fully understood (Brown
2004
;Rai
2010
).
Three
examples
below
highlight
the
importance
of
biotechnologies
and
biomimetics for civil engineering.
The first one relates to Ordinary Portland cement (OPC) concrete, a typical civil
engineering construction material, being the most used material on the Planet
Earth. Its production reaches 10.000 million tons/year and in the next 40 years
will increase around 100 % (Pacheco-Torgal et al.
2013a
). Currently around 15 %
of the total OPC production contains chemical admixtures to modify their prop-
erties, either in fresh or hardened state. Concrete super plasticizers based on
synthetic polymers include melamine, naphthalene condensates or polycarboxylate
copolymers. Environmental concerns justify a growing trend to the use of
admixtures based on renewable bio-based feedstocks and or capable of biodeg-
radation. Examples of biopolymers used in concrete include for instance ligno-
sulfonate, pine root extract, protein hydrolysates or even vegetable oils.
Biotechnological admixtures processes made in fermentation processes by using
bacteria or fungi seem to receive an increase attention. This includes sodium
gluconate, curdlan or Welan gum (Planck
2004
,
2005
).
An important biomimetic application for civil engineering concerns bio-
inspired structural design. For instance, deployable structures can be mentioned
among shape morphing structures that can change shape like the wing of the
insects or the petals of the flowers or like the movable structure of human body
(Friedman and Ibrahimbegovic
2013
). These structures were born by the appli-
cation of the basic ideas of tensegrities, as the foldable bridge realization, proposed
by Rhode-Barbarigos et al. (
2012
). The tensegrity concept was born from the
exceptional work of the inventor Buckminster Fuller (
1962
) aiming at maximal
structural efficiency. He coined the word ''tensegrity'' from tensile integrity and
defined it as ''islands of compression inside an ocean of tension'' (Kawaguchi
2002
).
Snelson (
1965
) also worked on the tensegrity field termed as ''floating com-
pression'' system and much later the cell biologist and bioengineer Ingber (
1998
)
defined this concept as ''the architecture of life.''
Another important biomimetic civil engineering-related issue concerns biomi-
metic building ''skins.'' The kinetics and adaptability implicit in this concept are
quite the opposite of current trends on passive building design approach (Loonen
et al.
2014
; Schleicher et al.
2014
; Reichert et al.
2014
). Of course this concept
would not make any sense in a heavy polluted city but only in a biophilic city. The
concept of biophilia, popularized by Harvard myrmecologist and sociobiologist
E.O. Wilson is defined as—the innately emotional affiliation of human beings to
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