size modules that can be transportable within
the road systems in Singapore. The size and
dimensions of each module is controlled by the
transportation constraints. Therefore, during the
early design stage, the initial early involvement
with all stakeholders, client, consultants,
authorities were all-important and played a part
in the successful implementation of the project.
Other considerations like hoisting weight limit
of the tower crane and access were all studied,
planned and not left to chance.
The weight of PPVC modules ranges from 18
to 30 tons. There are in total 1,866 PPVC modules
for the whole project: 862 in Tower 1 and 1004 in
Tower 2. Please refer to Figure 1 Modularisation
Plan for Tower 1 and 2.
For this project, the size of PPVC modules
were designed to be transportable under the
local traffic authorities’ guidelines. Care had
been taken to avoid traffic police escorts, which
would inevitably increase costs and also take
more time. Focus was on a just-in-time delivery
system where the timing for continuous seamless
lifting of modules into place did not disrupt the
construction schedule.
Overall, after much cost-benefit analysis
and deliberation over various options of the
manufacturing process, a single-minded approach
or process was adopted for the PPVC: from
concrete carcasses to fit-out works carried out in
factories, and afterwards assembling and stitching
the modules on site with minimum wet works.
Process, Factory and Installation
Basically, the typical PPVC module is a precast
six-sided RC module comprising a floor slab, a
ceiling slab, two side structural walls and two end
non-structural wall/doors. The PPVC concrete
carcasses with embedded M&E services’ pipes
were all manufactured off-site. To ensure water-
tightness, stringent quality checks were put in
place. For example, early structural ponding tests
were carried out at the precast factory to check for
water-tightness of the concrete floor structures.
The completed PPVC concrete carcasses were
delivered to the fit-out factory in Singapore for
architectural finishing (floor finishes, wall finishes,
painting, window frames & glazing, doors and
wardrobes and cabinets) and M&E fit-out works
(water & sanitary pipes, electrical conduits &
ducting, electrical sockets and light switches).
Figure 1: PPVC Modularisation
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