The Civil Engineering Contractor October 2018 | Page 25

ON SITE
fly ash, and silica fume delivered at a
60–70mm slump. We can guarantee
strengths from 25 to over 80mpa.
The core results for this site showed
compressive strengths ranging from
70–80mpa, says Strever.
Sustainability continues to grow as
a driving force in the decision-making
of owners and specifiers regarding
construction materials and placement
strategies. Because shotcrete is simply a
method of placing concrete, it offers all
of the sustainability benefits of concrete
as a building material in addition to a
long list of advantages that are unique
to the shotcrete method of placement,
explains Strever:
• Formwork savings of 50–100%
over conventional cast-in-place
construction;
• Formwork does not have to be
designed for internal pressures;
• Complex shapes require very
little, if any, formwork;
• Crane and other equipment
savings or elimination;
• Labour savings of at least 50% in
repair applications;
• New construction speed savings
of 33–50%;
• Speed of repair reduces or
eliminates downtime;
• Better bonding to the substrate,
which enhances durability;
• Adaptability to repair surfaces
that are not cost-effective with
other processes; and
• Ability to access restricted
space and difficult-to-reach
areas, including overhead and
underground.
The business model for wet shotcrete
is more suited to relatively large jobs,
where 25m 3 to 40m 3 has to be placed
a day or the formwork is excessively
complicated (conical structures, for
example). “The cost of equipment and
labour on site does not vary much with
quantities, so it can get expensive on
smaller quantities,” Strever explains.
“It requires some planning of quantities
to make best use of the shotcrete
method.”
Dustin Strever, director of
Shotcrete Africa.
List of contractors
Client: South Point
Contractor: Liviero Building
Architect: LYT Architects
Civils: ADA Consulting
Quantity surveyor:
Ethics Quantity Surveyors
Earthworks consultant:
ADA and Crossman Pape
Earthworks contractor:
Harrowgate
Geotechnical:
VNA Piling, Shotcrete, Crossman &
Pape, and ADA
Asbestos removal:
Dracon Demolitions
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