Concrete future - Concrete Mix Design, Quality Control and Specification - page 300

Boat ramp
An extremely innovative application made possible under a research
and development (R&D) project by QLD Transport and Main Roads,
Department of Maritime Safety. The existing in situ concrete boat ramp
at Rocky Point, Bundaberg, was due for replacement due to severe dete-
rioration. Wagners were awarded an R&D tender to replace the ramp
using an entirely novel form of construction material: precast concrete boat
plank units made from grade 40 geopolymer concrete and reinforced with
glass fibre reinforced polymer (GFRP) reinforcing bar. The approach slab
on ground to the ramp was made from site cast geopolymer and similarly
reinforced with GFRP. The project was successfully completed during
November and December 2011, as seen in Figure 13.6. The precast ramp
units were manufactured at Wagners precast facility in Toowoomba, while
the site cast geopolymer for the approach slab was batched in Toowoomba,
trucked to site with a 6.5-hour transit time, and then activated with the
chemical activators on site. A unique feature of this particular geopoly-
mer is that the entire batch constituents can be mixed in a truck bowl and
remain completely dormant until the activator chemicals are added.
Precast bridge decks
One of the earliest fully structural applications of this geopolymer was the
Murrarie Plant site bridge. This is a composite bridge structure made from
pultruded fibreglass girders acting compositely with a grade 40 geopolymer
bridge deck. The bridge was prefabricated at Wagners Toowoomba CFT
factory and brought to site for installation in 2009, as seen in Figure 13.7.
The bridge has been successfully in service since that date with continual
concrete agitator truck loadings and no signs of distress.
The Bundaleer Road Bridge, West Moggill, Brisbane, was constructed
and installed during May and June 2012, as shown in Figure 13.8. This
project is another example of a composite pultruded girder and grade 40
Figure 13.6 Boat ramp constructed with both precast and in situ geopolymer concrete.