DEMAND FOR TALL BUILDINGS COURSE OF DEVELOPMENT OF TALL BUILDINGS STRUCTURAL CONCERNS CONSTRUCTION METHODS FUTURE TALL BUILDINGS

2. CONTENTS
• INTRODUCTION
• DEMAND FOR TALL BUILDINGS
• COURSE OF DEVELOPMENT OF TALL BUILDINGS
• STRUCTURAL CONCERNS
• CLASSIFICATION OF TALL BUILDING STRUCTURAL SYSTEM
• FOUNDATION USED
• CONSTRUCTION METHODS
• FUTURE TALL BUILDINGS
• CONCLUSION

3. INTRODUCTION AND DEFINITION
Tall Buildings as defined by Council On Tall Buildings And Urban Habitat
Buildings higher than 50m is termed
as Tall Building.
Buildings higher than 100m is termed
as skyscraper.
Buildings 300m or higher is termed
as super tall.
Buildings 600m or taller is termed as
mega-tall.

4. Measurement of Height of tall buildings
Height to Architectural top
Height to tip
Highest Occopied floor

5. DEMAND FOR HIGH-RISE BUILDINGS
•Scarcity of land
•Increasing demand for buisness and residential space
• Economic growth
•Technological advancement
•Innovations in structural systems
•Cultural significance and prestige
•Human aspiration to build higher

6. DEVELOPMENT OF STRUCTURAL SYSTEMS
First Generation(1780-1850 )
Second Generation (1850-1940 )
.
Third Generation (1940-present )
HOME INSURANCE BUILDING
EMPIRE STATE BUILDING

7. TALL BUILDING TRENDS IN RECENT TIME
A composite tall building
utilizes a combination of
both steel and concrete
acting compositely in the
main structural elements.
A mixed—structure tall
building is any building
that utilizes distinct steel
or concrete systems
above or below each
other.
Structural material usage from 1930 to 2013

8. STRUCTURAL CONCERNS
The primary structural skeleton of a tall building can be visualized as a vertical cantilever
beam with its base fixed in the ground. The structure has to carry the vertical gravity
loads and the lateral wind and earthquake loads.
Gravity loads are caused by dead and live loads. Lateral loads tend to snap the building
or topple it. The building must therefore have adequate shear and bending resistance
and must not lose its vertical load-carrying capability.
The skyscraper pushes down on into the ground
.But when the wind blows, the columns in the
windy side stretch apart, and the columns on the
other side squeeze together.

9. INTERIOR STRUCTURES
By clustering steel columns and beams in the core, engineers
create a stiff backbone that can resist tremendous wind
forces. The inner core is used as an elevator shaft , and the
design allows lots of open space on each floor
EXTERIOR STRUCTURES
In newer skyscrapers, like the Sears Tower in Chicago,
engineers moved the columns and beams from the core to
the perimeter, creating a hollow, rigid tube as strong as the
core design, but weighing much, much less.
CLASSIFICATION OF TALL BUILDING STRUCTURAL
SYSTEMS

10. INTERIOR STRUCTURAL SYSTEM
•RIGID FRAME
Seagram building
Shear wall core
• SHEAR WALLSTRUCTURE

11. Shangai World
financial
centre
•OUTRIGGER STRUCTURES
INTERIOR STRUCTURAL SYSTEM

13. EXTERIOR STRUCTURES
•Tube system
The different tubular systems are-
1)Framed tube 2)Braced tube 3)Bundled tube 4)Tube in tube

14. •Diagrid systems
Hearst tower , New
York
EXTERIOR STRUCTURES
•Space truss
Bank of China, Hong Kong

15. •Exo skeleton structure
Hotel de las Atres
EXTERIOR STRUCTURES
•Super frame structures

16. • Raft foundation: one of the most common foundation. It is known for
its load distributing capability. With the usage of this type of
foundation the enormous load of the building gets distributed & helps
the building stay upright and sturdy. Loads are transferred by raft
into the ground.
• Pile foundation: used for high rise construction. load
of building is distributed to the ground with the help
of piles. Transfer the loads into the ground with an
Adequate factor of safety.
• Combined raft-pile: the hybrid of 2 foundation. It
Consists of both the pile anw bead raft foundation.
Useful in marshy sandy soil that has loring capacity.
FOUNDATION TYPES

17. CONSTUCTION METHODS AND TECHNIQUES
Slip forming, continuous poured, continuously formed, or slip form
construction is a construction method in which concrete is poured into
a continuously moving form. Slip forming is used for tall structures (such as
bridges, towers, buildings, and dams), as well as horizontal structures, such
as roadways. Slip forming enables continuous, non-interrupted, cast-in-place
"flawless" (i.e. no joints) concrete structures which have superior
performance characteristics to piecewise construction using discrete form
elements. Slip forming relies on the quick-setting properties of concrete, and
requires a balance between quick-setting capacity and workability. Concrete
needs to be workable enough to be placed into the form and consolidated
(via vibration), yet quick-setting enough to emerge from the form with
strength. This strength is needed because the freshly set concrete must not
only permit the form to "slip" upwards but also support the freshly poured
concrete above it.
In vertical slip forming the concrete form may be surrounded by a platform
on which workers stand, placing steel reinforcing rods into the concrete and
ensuring a smooth pour. Together, the concrete form and working platform
are raised by means of hydraulic jacks. Generally, the slipform rises at a rate
which permits the concrete to harden by the time it emerges from the bottom
of the form

18. SLIP FORM CONSTRUCTION
Slipforming is an economical, rapid and accurate
method of constructing reinforced concrete. At its
most basic level, slipforming is a type of movable
formwork which is slowly raised,
allowing the continuous extrusion of concrete.

19. TABLE FORM/FLYING FORM
A table form/flying form is a large pre-assembled
formwork and falsework unit, often forming a
complete bay ofsuspended floor slab. It offers
mobility and quick installationfor construction
projects with regular plan layouts or longrepetitive
structures, so is highly suitable for flat slab,
andbeam and slab layouts. It is routinely used for
residential flats, hotels, hostels, offices and
commercial buildings.
19

20. SYSTEM COLUMN FORMWORK
The column formwork systems now available are normally
modular in nature and allow quick assembly and erection
on-site while minimising labour and crane time. They
are available in steel, aluminium and even cardboard
(not reusable but recycled) and have a variety of internal
face surfaces depending on the concrete finish required.
Innovations have led to adjustable, reusable column forms
which can be clamped on-site to give different column sizes.

21. VERTICAL PANEL SYSTEMS
Crane-lifted panel systems are commonly used on
building sites to form vertical elements and usually
consist of a steel frame with plywood, steel, plastic
or composite facing material. The systems are
normally modular in nature, assembly times and
labour costs are considerably lower than traditional
formwork methods with far fewer components
required. They offer greater opportunities for reuse
for different applications on site. Panel systems are
extremely flexible and the larger crane-lifted
versions can be used for constructing standard
concrete walls, perimeter basement walls, columns
and in conjunction with jump form climbing systems.

22. TUNNEL FORM
Tunnel form is used to form repetitive
cellular structures, and is widely
recognised as a modern innovation that
enables the construction of horizontal
and vertical elements (walls and floors)
together. Significant productivity
benefits have been achieved by using
tunnel form to construct cellular
buildings such as hotels, low- and high-
rise housing,hostels,student
accommodation, prison and barracks
accommodation.

23. FUTURE TALL BUILDINGS
Nothing could be more stunning than the latest generation of skyscrapers, known as the
'supertalls'.A tower has to be over 300 metres high to qualify as a supertall, but there is
no shortage of contenders: at 829.8 metres high, the Burj Khalifa in Dubai is undeniably
the world’s tallest building, but it won’t be for very long as the race to build upwards
continues around the world.
We are entering the era of the “megatall.” This term is now officially being used by the
Council to describe buildings over 600 meters in height, or double the height of a
supertall .

24. CONCLUSION
With the present technology and known materials , it is possible to build more
higher and faster.
It is now possible to build skyscrapers so fast using pre- fabricated units that it
can lead to environmental problems, stress on resources and overcrowding if
not controlled.
To build higher the base of the building will have to be made wider. The
bundled tube system was a great innovation and was able to span great
heights during it's time , to attain the height of burj khalifa the bundled tube
system will need a bigger base when compared with the buttressed core
system.
New improved structural systems and new materials in the future can lead us
to even greater heights and more stable buildings. It’s not technology holding
buildings back. It’s money.

25. THANK YOU !