Construction World July 2015

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Professor Kourosh Kayvani, Aurecon's global building
design leader and one of Australasia's leading structural
engineers, discusses the key historic developments,
technological advances, current trends and engineering
considerations of high-rise buildings.
Where the tall building phenomena started
Vertical habitation isn’t a new trend. It’s one that has been driven by
urbanisation and bustling, overpopulated cities for centuries. While the
high-rise buildings that we know today became possible with the inven-
tions of elevators, newer building materials and structural engineering
systems, multi-storey construction dates back to the Roman Empire
and vertical cities have been around for centuries.
PROJECT PROFILE
A living example is the 16th century Yemeni city of Shibam with mud
brick tower houses of five to eight stories high built to protect the occu-
pants from Bedouin attacks.
Social, economic and technological developments in the latter
parts of the 19th century created the environment for modern high-rise
buildings to emerge in the North American cities of New York
and Chicago.
Daring engineering feats of the 1800s
In 1852, Elisha Graves Otis built the first ‘fall safe’ hoisting system (the
elevator) allowing vertical transportation of people and goods in multi-
storey buildings. This invention made the construction of skyscrapers
possible and as a result greatly altering the way modern cities were
planned and constructed.
In 1885, the Home Insurance Building in Chicago (originally 10
stories and 42 m high) demonstrated the use of the first steel framed
gravity system. It was the first tall building to be supported both inter-
nally and externally by a fireproof metal frame, which allowed for large
windows at the ground level of high-rise buildings.
This set the trend for use of steel frame gravity systems in tall build-
ings as the loadbearing masonry system used to that date was very
inefficient economically beyond 15 stories. This limitation is evidently
demonstrated by Monadnock Building (1893) in Chicago which, at 17
stories high, was the tallest in the world at the time and was the first
in use of a portal system for wind bracing. However, owing to its load-
bearing masonry system, it had walls up to 1,8 m thick at the ground
level that made the ratio of its ‘net-lettable-area’ to its total built area
simply too low to be economical.
In 1889, the Eiffel Tower doubled the height of the previously tallest
Washington Monument, rising above 300 m with the use of pre-as-
sembled iron components to create what has since become the iconic
landmark of Paris. This new architectural concept at the time provided
a great boost in general confidence in viability of tall metal structures.
The Ingal Building (now called the Transit Building) built in 1903
in Cincinnati in the United States of America is considered to be the
first reinforced concrete skyscraper. This 16-storey building was built
by monolithically casting the columns, floors and walls in concrete of
relatively low strength by modern standards.
Cincinnati architectural firm Elzner & Anderson designed what was
considered a daring engineering feat at the time (people feared the
building would collapse under wind loads or its own weight), but the
success of the building led to the team creating the tallest reinforced
concrete structure.
From the 1950s through to the 1970s, great technological advance-
ments took place that allowed architects and engineers to aspire to
greater heights. Some of these advancements included high-strength
bolts replacing hot-driven rivets, the emergence of glass-metal curtain
wall façades, the use of electric arc welding in shop fabrication and the
compressive strength of concrete catapulting from 40 MPa in the 1960s
to 65 MPa in the 1970s (and eventually 100 MPa+ in the 1990s).
These technological advances, combined with a deeper under-
standing of structural behaviour and analysis under environmental
loads (particularly wind loads), led to the emergence of supertall build-
ings being built in Chicago during the 1960s and 1970s. These supertall
buildings were conceived by structural engineers as tubular schemes
where the entire structure was designed as a cantilevered tube) or a
bundle of tubes resisting wind loads.
TALL BUILDINGS
– past and present trends
The motivation to build tall has
changed over time, as has the definition
of ‘tall’, the materials we use and the
designs that are possible. The passion,
obsession and necessity of building
supertall and mega tall structures
continues to challenge engineers and
architects to reach new heights and ‘go
where no man has gone before’.
An example of a location that has a large number
of super skinny tall buildings is New York City,
where each apartment is a penthouse that
occupies an entire floor of the building.
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CONSTRUCTION WORLD JULY 2015