Nelson Retaining Wall
Nelson Retaining Wall
TRANSIT MIX and Allied Concrete Ltd Nelson have completed the supply of spray mix for a retaining wall along Rocks Road Nelson.
The
spray mix was used on a near vertical rock face to consolidate the bank
in behind three new apartment blocks, one of which has been completed
with two others still in progress.
The
first spraying was done for Lacklan Construction from Wellington. This
was to retain a 1200 square metre rock face which was 80 metres long.
The next spraying was completed for Kidson Construction of Nelson and
the third spraying was for Gibbons Construction of Nelson. Total
sprayed altogether on the three projects was close to 900 cubic metres.
Allied Concrete’s Peter Stringer explains why Microsilica was included
in the mix. “Because of the slope of the banks to be spayed,
Microsilica was used to help hold the sprayed concrete in place and
also to add density to the product, giving a more water resistant
structure.”
“The sites were cut into terraces, and as the spraying on one face was
completed the next face was cut out ready for mesh and spraying,” added
Peter. “The thickness of the sprayed concrete walls ranged from 100mm -
500mm in cavities. Anchors were spaced 300mm apart and drilled up to 14
metres into the rock, using 32mm bar to hold the finished spray job in
place.”
“These were the first major sprayed retaining walls in the Nelson area. “Testing of the mix – with the use
of Microsilica – was completed before the commencement of the project with very good results.”
“The end result has been a product that has met the requirements for
this length of wall which is near vertical throughout the entire
length. All the contractors involved were very pleased with the
finished product.”