INGENIEUR
Design Codes and Standards
Design of the structures are based on the following
design codes and standards:
Loading
SS EN 1991-1-1: 2008 – General Actions
– Densities, Self-weight, Imposed Load for
Buildings
SS EN 1991-1-4: 2008 – General Actions –
Wind Actions
NA to SS EN – Singapore National Annex to
the relevant Eurocodes
Design
SS EN 1990: 2008 – Basis of Structural
Design
SS EN 1992-1-1: 2008 – Design of Concrete
Structures
NA to SS EN – Singapore National Annex to
the relevant Eurocodes
Tower Lateral Load Performance
ETABS software was used to model the
performance of the tower blocks under lateral load.
The building top displacement and inter-storey drift
ratio are controlled to be less than 1/500.
Tower Robustness
The tower blocks were checked for robustness
under notional horizontal load until such that
they were capable of resisting a ultimate notional
horizontal load applied at each floor or roof level
simultaneously equal to 1.5% of the characteristic
dead weight of the structure, between mid-height
of the storey below and mid-height of the storey
above in accordance with SS EN 1992-1-1:2008
and the Singapore National Annex.
Structural ties such as horizontal floor ties and
vertical ties were provided and checked to comply
with the provisions in SS EN 1992-1-1:2008 and
the Singapore National Annex.
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Durability
The structures were designed to Structural Class
S4 (Design working life of 50-years) with Exposure
Class XC3 (Corrosion induced by carbonation -
moderate humidity) to SS EN1992-1-1:2008 and
the Singapore National Annex.
Fire Resistance
The structures were designed for a fire resistance
of 1.5 hours. Fire compartmentalisation was
achieved by the separation of floors by the floor
slabs, separation of vertical compartments by
RC wall or rated partition; for plumbing risers
located within the PPVC units, the horizontal
compartmentalisation was maintained with the
risers segmented into separate compartments at
each floor.
PPVC Modularisation
Conceptually, the idea was to think of the tower to
be made up of modules that can be assembled
on site. So naturally the starting point was to
envisage the building as ‘’Lego-blocks” or bite-