42
CONSTRUCTION WORLD
NOVEMBER
2016
FORMWORK AND SCAFFOLDING
Il Dritto (The Straight One), Lo Storto (The Twisted One)
and Il Curvo (The Curved One) – the names given to the
three skyscrapers at Milan´s Piazza Tre Torri, the core of the
ambitious CityLife urban development project. Lo Storto, The
Twisted One, is the future administrative building of the Generali Insur-
ance Group. The 44 floors of the 170 m high-rise office building gracefully
wind their way upwards. It was designed by the recently deceased star
architect, Zaha Hadid. Likewise part of the CityLife project, the Hadid
Residences also feature her distinctive style and clear design language.
The concrete shell of the striking Generali Towers was completed in
April 2016 – after a construction phase of only 17 months. With the help
of project-specific PERI formwork operations, it was possible to finish
ahead of the originally planned schedule by a full three months. This was
because the formwork and scaffolding specialists at PERI Italy developed
an execution solution with consistently safe and thereby fast operating
sequences. In spite of the complicated building geometry, the standard
storeys could be realized in continuous weekly cycles.
One climbing system as protection panel and
climbing formwork
The PERI project solution was based in particular on the RCS Rail Climbing
System. On the one hand, this was used as a climbing protection panel
for the top floors under construction at any one time. In addition, the
RCS system served as climbing formwork for the building’s core. Through
the rail-guided climbing operations, the climbing units were securely
connected to the building at all times which ensured the climbing proce-
dure was always carried out quickly and safely even during windy condi-
tions. By means of mobile climbing hydraulics, the units could be lifted to
the next section each time without requiring a crane.
Climbing combination for the core
The floor slabs revolve around the centrally-positioned core of the high-
rise building whose complicated ground plan geometry is composed
of circular and angular external walls as well as contrasting slender
internal walls. Furthermore, the external walls of the core taper in 15 cm
increments from a massive 90 cm at the base to a much thinner 30 cm in
the upper floors.
The PERI climbing formwork solution was based largely on the
crane-independent working RCS Rail Climbing System, combined with a
self-climbing ACS Platform Unit along with crane-climbed CB Climbing
Platforms and BR Shaft Platforms. With the help of the ACS technology,
the placing boom could also be guided upwards. The reinforced concrete
walls were formed accordingly using TRIO Panel Formwork and VARIO
Girder Wall Formwork, supplemented by project-specific special form-
work elements.
Maximum safety and fast shuttering times
The RCS P Climbing Protection Panel secured the leading edges of the
twistedly-arranged floors so that the walls, columns and slabs could be
safely formed at all times. In addition, the increased feeling of safety –
due to the gap-free enclosure – accelerated the construction progress
ensuring that forming operations could continue throughout inde-
pendent of wind and weather.
For realizing the 32 cm thick floor slabs, SKYDECK Panel Slab Form-
work complete with the drophead system was used. In the process, fast
shuttering times with short striking times were achieved. Problem-free
adaptation to suit the slab geometry which changed from storey to storey
as well as shuttering the columns was carried out by means of standard
compensation elements.
PROKIT anti-fall protection usefully supplemented the PERI execu-
tion solution and consistently implemented the safety concept in all
floors for all shell construction operations and finishing work. With side
mesh barriers, posts and slab feet, flexible use without any additional
planning effort for accommodating the complex building geometry also
proved to be unproblematic.
TWISTED
high rise architecture
The 170 m high office tower in Milan elegantly
winds its way upwards and bears the signature
of Zaha Hadid. Through the interplay of
perfectly coordinated formwork and scaffolding
solutions on the basis of a well thought-out
safety concept, the shell construction could be
completed within just 17 months.
>
The 170 m high office tower bears – as does the residential development
section of the Milan CityLife project – the handwriting of the recently
deceased star architect, Zaha Hadid. (All hotos: PERI GmbH)
The 44 storeys elegantly wind their way upwards from the ground.
I