HIGH RISE

STRUCTURAL SYSTEMS
Architectural Building Construction - SEMESTER - VII (4TH YR) 2017-18
Prof.Sandeepkumar Prajapati
A LOW RISE / HIGH RISE BUILDING AS DEFINED BY
EMPORIS DATA COMMUNITY

-low-rise building (ESN 49213 )

Definition:
A low-rise building is an enclosed structure whose architectural height is below
35 meters, and which is divided at regular intervals into occupiable levels. It
encompasses all regular multi-story buildings which are enclosed, which are
below the height of a high-rise, and which are not entirely underground.

-high-rise building (ESN 18727 )

Definition:
A high-rise building is a structure whose architectural height is between 35 and
100 meters. A structure is automatically listed as a high-rise when it has a
minimum of 12 floors, whether or not the height is known. If it has fewer than 40
floors and the height is unknown, it is also classified automatically as a high-rise

https://www.emporis.com/building/standard/15/low-rise-building
INTRODUCTION AND DEFINITION
High rise is defined differently by different
bodies.

Emporis standards- The International Conference on

“A multi-story structure between 35- Fire Safety –
100 meters tall, or a building of "any structure where the height can
unknown height from 12-39 floors is have a serious impact on evacuation“
termed as high rise.

Building code of Hyderabad,India- Massachusetts, United States

General Laws –
A high-rise building is one with four A high-rise is being higher than 70 feet
floors or more, or one 15 meters or (21 m).
more in height.
Classification according to structural behavior
Structural Loads • Gravity loads
– Dead loads
– Live loads
– Snow loads

• Lateral loads
– Wind loads
– Seismic loads

• Special load cases

– Impact loads
– Blast loads

Wind
Loads

Seismic Loads
STRUCTURAL CONCERNS
STRUCTURAL CONCERNS
Lateral force system
STRUCTURAL CONCERNS

overturning bending shear racking

-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.
-A rigid or semi-rigid frame will deform under lateral loads in two ways: a) cantilever bending and b) shear sway
distortion
-The combination of these represents the actual behavior of the frame structure.
-Stiffening the frame with x-bracing, for example, will cause more cantilever bending and less shear sway
STRUCTURAL CONCERNS
Fighting gravity
-The weight of the building is
supported by a group of vertical
coloumns
-Each floor is supported by horizontal
steel girders running between vertical
coloumns.
-Curtain wall m ade of ste e l a n d
concrete attaches to the outside

Wind resistance
-Buildings taller than 10 storeys would generally require additional steel for lateral
system.
-The most basic method for controlling horizontal sway is to simply tighten up the
structure. At the point where the horizontal girders attach to the vertical column,
the construction crew bolt: and welds them on the top and bottom. as well as the
side. This makes the entire steel super structure move more as one unit, like a
pole, as opposed to a flexible skeleton.
STRUCTURAL CONCERNS
• For taller skyscrapers, tighter connections don't really do the trick
To keep these buildings from swaying heavily. Designers have to
construct especially strong cores through the center of the
building.
• The effects of wind can also be minimized by aerodynamic
shaping of the building. Wind tunnel testing considers appropriate
loading for overall lateral system design and cladding design, and
predicts motion perception and pedestrian level effects.
• Use of damping systems

(as the building becomes taller and the building’s sway

due to lateral forces becomes critical, there is a greater
demand on the girders and columns that make up the
rigid-frame system to carry lateral forces.)
CLASSIFICATION OF TALL BUILDING
STRUCTURAL SYSTEMS
• Can be classified based on the structural material used such as concrete or
steel
• Structural systems of tall buildings can also be divided into two broad
categories:
• 1)INTERIOR STRUCTURES
• 2)EXTERIOR STRUCURES
• This classification is based on the distribution of the components of the
primary lateral load-resisting system over the building. A system is
categorized as an interior structure when the major part of the lateral load
resisting system is located within the interior of the building. Likewise, if the
major part of the lateral load-resisting system is located at the building
perimeter, a system is categorized as an exterior structure. It should be
noted, however, that any interior structure is likely to have some minor
components of the lateral load-resisting system at the building perimeter,
and any exterior structure may have some minor components within the
interior of the building.
 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.
INTERIOR STRUCTURAL SYSTEM
1)RIGID FRAME
-A rigid frame in structural engineering is
the load-resisting skeleton
constructed with straight or curved
members interconnected by mostly
rigid connections which resist
movements induced at the joints of
members. Its members can take
bending moment, shear, and axial
loads.
-Consist of columns and girders joined by
moment resistant connections.
-Can build upto 20 to 25 floors

Seagram building
2)SHEAR WALL STRUCTURE
-Concrete or masonry continuous vertical walls may serve both
architecturally partitions and structurally to carry gravity and
lateral loading. Very high in plane stiffness and strength make
them ideally suited for bracing tall building
-Usually built as the core of the building
Shear wall core -Can build upto 35 Floors
Shear wall system
• A type of rigid frame construction.
• The shear wall is in steel or concrete to provide greater lateral rigidity. It is a wall where the entire
material of the wall is employed in the resistance of both horizontal and vertical loads.
• Is composed of braced panels (or shear panels) to counter the effects of lateral load acting on a
structure. Wind & earthquake load are the most common among the loads.
• For skyscrapers, as the size of the structure increases, so does the size of the supporting wall.
Shear walls tend to be used only in conjunction with other support systems.
3)OUTRIGGER STRUCTURES
• The core may be centrally located with
outriggers extending on both sides or
in some cases it may be located on one
side of the building with outriggers
extending to the building columns on
the other side Shanghai World
• The outriggers are generally in the financial centre
form of trusses (1 or 2 story deep) in
steel structures, or walls in concrete
structures, that effectively act as stiff
headers inducing a tension-
compression couple in the outer
columns.
• Belt trusses are often provided to
distribute these tensile and
compressive forces to a large number
of exterior frame columns.
• An build upto 150 floors
 EXTERIOR STRUCTURES
1)Tube system
•The tube system concept is based on the idea that a building can be designed to
resist lateral loads by designing it as a hollow cantilever perpendicular to the
ground. In the simplest incarnation of the tube, the perimeter of the exterior
consists of closely spaced columns that are tied together with deep spandrel
beams through moment connections. This assembly of columns and beams
forms a rigid frame that amounts to a dense and strong structural wall along the
exterior of the building.

The different tubular systems are-

1)Framed tube 2)Braced tube 3)Bundled tube 4)Tube in tube

 2)Diagrid systems
With their structural efficiency as a varied version of the
tubular systems, diagrid structures have been emerging as a
new aesthetic trend for tall buildings in this era of pluralistic
styles.
Early designs of tall buildings recognized the effectiveness of
diagonal bracing members in resisting lateral forces.
Most of the structural systems deployed for early tall buildings
were steel frames with diagonal bracings of various
configurations such as X, K, and chevron. However, while
the structural importance of diagonals was well recognized,
the aesthetic potential of them was not appreciated since
they were considered obstructive for viewing the outdoors.
Efficiently resists lateral shear by axial forces in the diagonal
members but have Complicated joints
Hearst tower , New York
3)Space truss
Space truss structures are
modified braced tubes with
diagonals connecting the
ex te ri o r to i nte r i o r. I n a
typical braced tube structure,
a l l t h e d i a go n a l s , w h i c h
connect the chord members
– vertical corner columns in
general, are located on the
plane parallel to the facades.
However, in space trusses,
some diagonals penetrate
the interior of the building.

Bank of China, Hong Kong

4)Exo skeleton structure
In exoskeleton structures,
lateral load-resisting systems
are placed outside the building
lines away from their facades.

Due to t h e syste m ’s
compositional characteristics,
it acts as a primary building
identifier – one of the major
roles of building facades in
general cases.

Fire proofing of the system is

not a serious issue due to its
location outside the building
line. Hotel de las Atres
5)Super frame structures
• Superframe structures can create ultra high-rise buildings upto
160 floors.
• Superframes or Megaframes assume the form of a portal
which is provided on the exterior of a building.
• The frames resist all wind forces as an exterior tubular
structure. The portal frame of the Superframe is composed of
vertical legs in each corner of the building which are linked by
horizontal elements at about every 12 to 14 floors.
• Since the vertical elements are concentrated in the corner
areas of the building, maximum efficiency is obtained for
resisting wind forces.
FRAMED-TUBE STRUCTURES
The lateral resistant of the framed-tube structures is provided by
very stiff moment-resistant frames that form a “tube” around the
perimeter of the building.

The basic inefficiency of the frame system for reinforced concrete

buildings of more than 15 stories resulted in member proportions
of prohibitive size and structural material cost premium, and thus
such system were economically not viable.

The frames consist of 6-12 ft (2-4m) between centers, joined by

deep spandrel girders.

Gravity loading is shared between the tube and interior column or

walls.

When lateral loading acts, the perimeter frame aligned in the

direction of loading acts as the “webs” of the massive tube of the
cantilever, and those normal to the direction of the loading act as
the “flanges”.

The tube form was developed originally for building of rectangular

plan, and probably it’s most efficient use in that shape.
THE TRUSSED TUBE Recently the use of perimeter diagonals – thus
the term “DIAGRID” - for structural effectiveness
and lattice-like aesthetics has generated renewed
interest in architectural and structural designers
of tall buildings.
The trussed tube system represents a classic
solution for a tube uniquely suited to the qualities
and character of structural steel.

Interconnect all exterior columns to form a rigid

box, which can resist lateral shears by axial in its
members rather than through flexure.

Introducing a minimum number of diagonals on

each façade and making the diagonal intersect at
the same point at the corner column.

The system is tubular in that the fascia diagonals

not only form a truss in the plane, but also interact
with the trusses on the perpendicular faces to
affect the tubular behavior. This creates the x form Introducing a minimum
between corner columns on each façade. number of diagonals on
each façade and
Relatively broad column spacing can resulted making the diagonal
large clear spaces for windows, a particular intersect at the same
characteristic of steel buildings. point at the corner
column
The façade diagonalization serves to equalize the
gravity loads of the exterior columns that give a
significant impact on the exterior architecture. John Hancock Center introduced
trussed tube design.
BUNDLED TUBE SYSTEM
The concept allows for wider
column spacing in the tubular
walls than would be possible
with only the exterior frame
tube form.

The spacing which make it

possible to place interior frame Sears Tower, Chicago.
lines without seriously
compromising interior space
planning.

The ability to modulate the

cells vertically can create a
powerful vocabulary for a
variety of dynamic shapes
therefore offers great latitude
in architectural planning of at
all building.

Burj Khalifa, Dubai.

TUBE-IN-TUBE SYSTEM Lumbago Tatung Haji Building, Kuala
Lumpur

This variation of the framed tube

consists of an outer frame tube, the
“Hull,” together
with an internal elevator and service
core.

The Hull and core act jointly in

resisting both gravity and lateral
loading.

The outer framed tube and the inner

core interact horizontally as the shear
and flexural components of a wall-
frame structure, with the benefit of
increased lateral stiffness.

The structural tube usually adopts a

highly dominant role because of its
much greater structural depth.
1 Bearing wall system Three types: cross wall system, long wall system and two-way system.
2 Wall-core system Lateral force resistance is shared between load bearing wall structure and service core structures.
2 Wall-core system Lateral force resistance is shared between load bearing wall structure and service core structures.
 3 Core-frame system The structural core acts as a shear wall. The frame may contribute also to the lateral stiffness,
depending on the type of frame. A hinged frame contributes nothing and only
carries vertical loads. A rigid frame contributes significantly.

Core and frame systems provide adequate stiffness up to 30-40 stories. Generally cores are at the center of the building, both
for practical reasons (daylight) and to resist shear forces more effectively. If not centered, they are usually symmetrically located.
Construction materials
Materials used for high rise buildings: concrete, steel, glass, cladding material, high alumina cement used for
roofs & floors. It contains bauxite instead of clay, cement, Portland cement of lime stone, silica.

CONCRETE:- cellular concrete of clay-gypsum &

Advantages are:
invention of light weight concrete.
 Plasticity FERRO CONCRETE:-it is layer of fine mesh
 Easily availability saturated with cement.
 Easy in casting GUNITE:- it is also known as shot Crete.
compressed air to shoot concrete onto (or
 Non corrosive into) a frame or structure. Shot Crete is frequently
 Can be cast in situ used against vertical soil or rock surfaces, as it
eliminates the need for
Disadvantages are: formwork.
 Cost of form GLASS:- float glass with double glass is used in tall
buildings .
 Dead weight
Tempered glass is used in tall buildings instead of
 Difficulty in pouring plain glass, as that would shatter at such height.
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
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.
TABLE FORM/FLYING FORM

A table form/flying form is a l ar ge pr e-

assembled formwork and falsework unit, often
forming a complete bay of suspended floor
slab. It offers mobility and quick installation for
construction projects with regular plan layouts
or long repetitive structures, so is highly
suitable for flat slab, and beam and slab
layouts. It is routinely used for residential flats,
hotels, hostels, offices and commercial
buildings.
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.
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
conjunct i on w i t h j um p f or m cl i m bi ng
systems.
JUMP FORM SYSTEMS
Gener al l y, j ump f or m syst ems c o m p r i s e t h e
formwork and working platforms for cleaning/fixing
of the formwork, steel fixing and concreting. The
formwork supports itself on the concrete cast earlier
so does not rely on support or access from other
parts of the building or permanent works.

Jump form, here taken to include systems often

described as climbing form, is suitable for
construction of multi-storey vertical concrete
elements in high-rise structures, such as shear walls,
core walls, lift shafts, stair shafts and bridge pylons.
These are constructed in a staged process. It is a
highly productive system designed to increase
speed and efficiency while minimising labour and
crane time.

Systems are normally modular and can be joined to

form long lengths to suit varying construction
geometries.

Three types of jump form are in general use:

TYPES OF JUMP FORM
Normal jump/climbing form – units
are individually lifted off the structure
and relocated at the next construction
level using a crane.

Guided-climbing jump form – also

uses a crane but offers greater safety
and control during lifting as units
remain anchored/guided by the
structure.

Self-climbing jump form – does not

require a crane as it climbs on rails
up the building by means of hydraulic
jacks, or by jacking the platforms off
internal recesses in the structure. It is
possible to link the hydraulic jacks
and lift multiple units in a single
operation.
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.
THANKS………………..