Advance construction
technology and structural
Unit-4 Space frames and shell
structures
systems
Presented by sayeeda
sumayya(17091AA051)
Space frames
Bank of China
Tower / I.M. Pei
❖ The Bank of China Tower (abbreviated BOC Tower)
is one of the most recognisable skyscrapers in
Admiralty, Hong Kong.
❖ It houses the headquarters for the Bank of China
(Hong Kong) Limited.
❖ The building is located at 1 Garden Road, in
Central and Western District on Hong Kong Island.
❖ Designed by I. M. Pei and L.C Pei of I.M Pei and
Partners, the building is 315.0 m (1,033.5 ft) high
with two masts reaching 367.4 m (1,205.4 ft) high.
❖ It was the tallest building in Hong Kong and Asia
from 1989 to 1992, and it was the first building
outside North America to break the 305 m (1,000 ft)
mark.
❖ It is now the fourth tallest skyscraper in Hong
Kong, after International Commerce Centre, Two
International Finance Centre and Central Plaza.
Bank of china tower
Structural construction
❖ The structural expressionism adopted in the
design of this building resembles growing
bamboo shoots, symbolising livelihood and
prosperity.
❖ The whole structure is supported by the five
steel columns at the corners of the building,
with the triangular frameworks transferring the
weight of the structure onto these five columns.
❖ It is covered with glass curtain walls.
❖ The structure follows space frame construction.
❖ A space frame is a structure system assembled
of linear elements so arranged that forces are
transferred in a three-dimensional manner.
❖ Bank of china tower is geometric triangular
grid pattern space frame structure.
Geometric triangular grid pattern space frame structure
❖ This structure follows four-way grid pattern.
❖ space frame geometry commonly used is the
triangular grid.
❖ Because of their triangular pattern, these
grids can resist in-plane twist.
❖ But as in square grids, their depth is limited
and, for a large portion of their extent, they
often contain more web members than are
necessary to carry the load.
❖ In order to overcome these disadvantages,
triangular grids may also benefit from the
modifications available to square grids.
Load distribution in triangular grid
Interiors
Construction process
❖ Hoisting of whole space frame by derrick
masts or cranes
❖ The whole space frame is assembled at
ground level so that most of the assembling
work can be done before hoisting. This will
result in increased efficiency and better
quality. For short and medium spans, the
space frame can be hoisted up by several
cranes.
❖ For long-span space frame, derrick masts are
used as the support and electric winches as
the lifting power.
❖ The whole space frame can be translated or
rotated in the air and then seated on its final
position. Under construction
❖ This method can be employed to all types of
double-layer grids.
Shell structure
Cooling towers of
Dukovany power station
❖ The Dukovany Nuclear Power Station is a nuclear
power plant near Dukovany, a village in the Czech
Republic..
❖ It was the second nuclear power plant in
Czechoslovakia (the Bohunice Nuclear Power Plant
in what is now Slovakia was constructed in 1958),
and the first one in what is now the Czech Republic.
❖ It is situated 30 kilometres (19 mi) from the city of
Třebíč, near the Dalešice Reservoir, where the plant
sources its water supply.
❖ In 1970 Czechoslovakia and the Soviet Union ratified
a contract for construction of two nuclear power
plants. Actual construction work began four years
later.
❖ Dukovany Nuclear Power Station has 8 cooling
towers, each 125 metres tall.
❖ A cooling tower is used to remove excess heat that is
generated in large industrial and commercial units
by cooling the area by lowering the temperature.
Cooling tower
Structural construction
❖ FORMS OF CURVATURE: RULED SURFACES :
RULED SURFACES ARE GENERATED BY
SLIDING EACH END OF A STRAIGHT LINE ON
THEIR OWN GENERATING CURVE. THESE
LINES ARE NOT NECESSARILY AT RIGHT
ANGLE TO THE PLANES CONTAINING THE
END CURVES.
❖ HYPERBOLIC PARABOLOID: FORMED BY
SWEEPING A CONVEX PARABOLA ALONG A
CONCAVE PARABOLA OR BY SWEEPING A
STRAIGHT LINE OVER A STRAIGHT PATH AT
ONE END AND ANOTHER STRAIGHT PATH
NOT PARALLEL TO THE FIRST.
❖ STRUCTURAL BEHAVIOURS: DEPENDING ON
THE SHAPE OF THE SHELL RELATIVE TO THE
CURVATURE, THERE WILL BE DIFFERENT
STRESSES. SHELL ROOFS, HAVE COMPRESSION
STRESSES FOLLOWING THE CONVEX
CURVATURE AND THE TENSION STRESSES
FOLLOW THE CONCAVE CURVATURE.
Hyperbolic paraboloid
Construction process
❖ These large cooling towers can be up to 200 metres (660 ft) tall
and 100 m (320 ft) in diameter.
❖ They are often constructed as hyperboloid, doubly-curved
concrete shell structures supported on a series of concrete
struts.
❖ The foundations typically consist of an inclined pond wall
forming a circular ‘tee’ beam with a wide concrete strip. The
beam acts to resist the lateral load of the tower’s shell
structure.
❖ As well as the ‘tee’ beam, piled foundations are normally
required to minimise differential settlement and reduce the
risk of cracking.
❖ The cooling system is housed in the tower’s base which is
typically the bottom 10 metres, the rest of the tower
consisting of an empty shell. The water falls and collects in a
pond at the base of the tower, formed by a base slab and the
pond wall.
❖ In natural-draught cooling towers the open structure at the
base allows a natural movement of air. Mechanical-draught
cooling towers use fans to provide a draught, where it is
necessary to maintain or not exceed a fixed temperature level.
The costs associated with the operation of mechanical-
draught may be higher, but it is more efficient than natural
draught.
Parts of the cooling tower
Direct stresses on a hyperboloid
