The Civil Engineering Contractor February 2018 | Page 29

INSIGHT
L
andfills are often seen as the solution
to disposing of plastic. Back in 2009, a
graduate from RPI Masters of Architecture
in the US, Henry Miller, observed that many
areas cut their plastic recycling programmes for
the cheaper solution of landfills, and noticed the
shocking number of brownfield sites that were
simply being abandoned.
Miller’s idea was to use plastic waste as an
aggregate in concrete and create another, useable
product. By reclaiming cement and soil from
the brownfields and mixing it with ground-up
plastic, Miller was able to create a material just
as strong as conventional concrete and, at the
time, netted him first place in the ‘Component
Category’ of the second annual Concrete
Thinking for a Sustainable World competition.
While on the other side of the globe, Australian
researchers from James Cook University (JCU)
have successfully reinforced concrete with
plastic waste rather than using steel. The lead
researcher from JCU found that short pieces of
recycled plastic can be added as reinforcement
in this material, and assured that “using recycled
plastic, we were able to get more than a 90%
saving on CO 2 emissions and fossil fuel usage
compared to using the traditional steel mesh
reinforcing.” He added that recycled plastic has
“obvious environmental advantages over using
virgin plastic fibres”.
According to the research, the concrete was
reinforced by using recycled polypropylene
plastic, and various tests show that the result
could be used to build footpaths and precast
elements such as drainage pits and concrete
sleepers. 
Plastic in-roads
Supplementing aggregate with waste plastic is
gaining traction, and the futuristic concept of a
plastic road is fast becoming a reality.
The idea for plastic roads originated from
VolkerWessels, a Netherlands-based construction
firm. According to the company, plastic roads would
be a “virtually maintenance-free product” that is
“unaffected by corrosion and the weather”. The roads
could handle temperatures as low as -40°C and as
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