and installation of the Acrylic ‘windows’, which
not only had a long lead time, but had been the
subject of an extensive international pre-contract
assessment. After numerous rounds of pricing and
due diligence on quality, an Italian firm, Clax Italia
srl, was appointed. Conventional JBCC contracts,
guarantees and the like all had to be translated into
Italian prior to si gnature.
The tank further had to be constructed in such a
manner, and to exact tolerances, so as to minimise
construction joints and to allow not only a perfect
fit for the acrylic panels, but to also facilitate
water tightness in order to achieve an acceptable
finish for waterproofing. The co-ordination of
the tank design and construction between the
client, engineers, main contractor, waterproofing
specialists and the acrylic supplier (who undertook
his own installation), was key to success of the
tank construction.
Apart from the requirements of the tank, the
project entailed the provision of new filtration plant
rooms, workshops and ‘back of house’ facilities for
the TOAT portion of the project for fit out by TOAT
staff. A further aspect of the development was
the construction, within the aquarium extension,
of an independently operated events space, and
facilities, that overlook the main acrylic window.
GROUND FLOOR PLAN
FIRST FLOOR PLAN
KEY TO PLANS
1 OCEAN EXHIBIT TANK
2 TUNNEL
3 DOUBLE VOLUME
4 EXHIBITION SPACE
5 LIFE SUPPORT
6 OFFICES
7 STAFF
8 CHEMICAL STORE
RIGHT:
SECTION AA
BELOW:
SECTION BB
52
9 REFUSE ROOM
10 DELIVERIES
11 DELIVERY AREA
12 WORKSHOP
13 TOILETS
14 CONFERENCE LOBBY
15 CONFERENCE ROOM
16 PLANT ROOM
17 STORE
18 PUMP ROOM
19 EXISTING AQUARIUM
20 OCEAN
21 ONE & ONLY HOTEL
22 DOCK ROAD
23 KITCHEN
24 ROOF DECK
25 EXISTING BUILDING
26 DIVING POOL
27 FEEDING / MEDICAL POOL
28 COVERED WALKWAY
PROJECT CHALLENGES
Excavation in Rock
It had been noted, during the geotechnical
investigation, that the underlying bedrock would
require drilling and blasting below 1.5m. This
was, however, not a concern until such time it
was realised through design review and the
identification of servitude access constraints
raised by the V&AW and the adjacent One &
Only Hotel that the storm water line needed
to be rerouted. This entailed excavating in hard
rock for almost 50m. At that point, blasting was
no longer feasible due to the advanced status of
the structural work and excavation continued by
pneumatic means and local shot blasting only. This
had a dramatic impact on the structural time line
and constrained the tank construction works.
Acrylic Removal and Waterproofing
The tank concrete was tested for water tightness
before the overall waterproof liner was installed,
but waterproofing membranes were installed
locally to the reveals so as to seal the acrylic
panels to the membranes. This, unfortunately, led
to water ingress behind these membranes due to
water pressure. This resulted in the Italian team
having to be mobilised and the acrylics having to be
removed again to effect repair of the waterproofing
membranes. During this time, the specification of
the waterproofing was re-considered.
An extensive review period followed to
identify not only the right product, but also the
Two Oceans Aquarium