It elaborately describes various retractable systems in a stadium and in general. The various types of retractable roofs, retractable seating and retractable stadiums. The materials used and design considerations are also disused sharply.

1. RETRACTABLE SYSTEMS
CONTEMPORARY ARCHITECTURE
Presented by:
Sahabaz, Shadab & Nihal
Recreational Architecture
Ist Semester

2. RETRACTABLE SYSTEMS
RETRACTABLE means something able to be pulled backwards or
inwards. It can also be referred as MOVABLE or SLIDING.
APPLICATIONS
It is used in different type of buildings like residences, sport stadiums, swim centre,
restaurants etc. Places where we wish to provide an open-air experience at the push of
a button.
Retractable Roof in pool Folding Roof in restaurant Retractable Seating Retractable Walls Office Space

3. RETRACTABLE SYSTEMS IN RESIDENCE
• The material used is aluminum (light weight, strong,
non-rustic)
• Polycarbonate (PC) sheets.
• tempered glass
• silent motors.
• rain sensors, wind sensors & timers
• Creates Desirable Outdoor
• Used to cover the patios, decks, swimming pools etc.
• Protects furnishings from fading outdoors and indoors.
• Block sunlight entering the room
• Retractable Skylights open up for maximum fresh air,
circulation, and unmatched views.

4. RETRACTABLE SYSTEMS IN STADIUMS
RETRACTABLE PARTS OF STADIUMS: Retractable Field
The retractable field is also known as a mobile pitch and movable grass
pitch. The introduction of a sliding pitch to the stadium design is a key
element in accommodating both sports within the venue.
A Retractable grass field
• When the pitch is rolled outside, a clean, flat
surface is exposed, which can be utilized for
trade shows, motor sporting events, concerts
etc .
• Turning a sports stadium into an event center
can involve a long, complex process of
removing pieces of a playing field or covering
up the field entirely. A retractable field not only
stores the field in an ideal location, but turns a
lengthy process into a simple and cost-effective
automated motion.

5. A natural grass playing field requires high-energy light and water to grow attractively. An indoor,
closed-atmosphere stadium can certainly house a natural field, but the benefits of an outdoor
atmosphere are still unbeatable.
With the capability to move an entire field outside, a facility owner can take even greater pride in
the look of the natural field.
COMPONENTS:
FOR RETRACTABLE MECHANIZED PART:
• Rail erection stool
• Tracks
• Concrete bed
• Girders
• Wheel box
• Motor
• Corrugated steel
• Concrete slab
FOR NATURAL GRASS PITCH:
• Plastic drainage mat
• Geotextile fabric
• Soil
• Irrigation pipes
• Natural turf

7. RETRACTABLE ROOF operable roofs or retractable skylights.
Used in buildings
•Residences
•Sport stadiums
•Restaurants
•Swim centres
In this method whole roof can be moved or drawn back within a
short time.
Roofing Materials of
Retractable Roof
Structures -
•Glass
•Polycarbonate
•EthyleneTetrafluoroethylene
(ETFE)
•Photovoltaic
Pittsburgh civic arena was the first stadium with
retractable roof structure which inaugurated in 1961 in
United States.
Implementation of such structures is costly,it can be
inferred that United Statesis the first country that
achieved these difficult and complicated structural
systems
Dallas cowboy Stadium Atlanta Stadium

8. Roof designed with tracks so as to convert any interior space into outdoor space. These roof
can be used in residences , bars, swim centres, etc. to provide open air experience.
Some specifications such as flexibility, beautification, and authentication have made suitable
this kind of construction for the wide span roof stadiums. According to this, the most
important view point in these special projects is how to cover the wide span open roofs.
Therefore, identification of structural systems used in these stadiums is important.
Singapore National Stadium

10. TYPES OF RETRACTABLE ROOFS IN
STADIUMS:
• Sliding and over lapping
• Umbrella
• Fan Shapes
• Accordion
Sky Dome Toronto (Sliding & Overlapping) Millers Park (Fan Shaped)
Wimbledon Central Court (Accordian)BC Place Canada (Umbrella)
Retractable roofs are normally
composed of rigid, steel moving
panels. Panels consist of
large steel trusses and are
powered by large, mechanical
drive systems. Retractable roofs
can move in a variety of
directions, including vertical,
horizontal, parallel, fan-shaped
revolving and central revolving.
There also different types of
retractions, including
overlapping, stacking and
folding, and roofs can be divided
into any number of sections.

11. SLIDING - RETRACTABLE ROOFS :
 Steel lattice of the movable roof structure slides along two main transverse beams by means of
wheels and electric motors. With movement of the roof elements the entire playing field opens up,
while stands remain under the fixed part of the roof.
 The stadium or industrial buildings commonly use 2-D panels roofs composed of steel frames with a
covering material as the structural system for their retractable roof.
Atlanta stadium (with 8-sided retractable roof)
Source: www.designboom.com/architecture/new-atlanta-stadium Source: www.designboom.com/architecture/new-atlanta-stadium
The roof of the
covered stadium is
composed of two
or more movable
elements, which
are moved
horizontally in the
transverse
direction of the
building.

12. Bank One Ballpark, Phoenix, Arizona
 The structure was designed to allow for large open concourses to
increase fan comfort. Generally, roofs for stadiums and industrial
buildings have some curvature, either arch like or dome shaped.
 The roof has eight panels-two being fixed and six able to
move. Each half of the roof can move independently and is cable-
driven using gantry crane technology.
 The six telescoping panels consist of trusses fitted with multi-
wheeled bogies at each end, and can be retracted in 4 1/2 minutes,
revealing a 5.3-acre opening to the sky.
 Each panel is supported by the panel beneath it and moves on a
steel wheel guide roller arrangement.
SLIDING & OVERLAPPING - RETRACTABLE ROOFS :
Source: www.ballparks.com
Source: www.pinterest.com

13. SLIDING & OVERLAPPING - RETRACTABLE ROOFS :
Conceptual 3D Form:
 The computer control system adjusts the roof opening in a
fashion similar to that of a camera aperture for the angle of the
sun, allowing the maximum amount of light on the field and the
least on the seats to reduce heat gain.
 The six, 800-ton panels are pulled by four miles of steel cable
attached to two gear boxes and two 200 horsepower electric
motors.
 To reduce the weight of the roof and its effect on the drive
mechanism, high-strength steel (65ksi) was used in the roof
trusses.
 This type of Panel systems are commonly used for large roof
areas, typically in the range of 5,000 m2 to as much as 50,000 m2

14. Source: “Clark Construction” - www.clarkconstruction.com/our-work Source: “The Chicago Curve” - http://www.cmrp.com/blog/
Miller Park in
Milwaukee, Wisconsin,
with its fan-shaped
retraction and
unique geometry,
required a great deal of
wind load studies.
Roof also had to be
designed with particular
attention paid to snow
loading and the various
patterns it could take
FAN SHAPED – RETRACTABLE ROOFS :
Miller Park, with a fan style roof
 The total roof span is covered using 8 panels, where 2 panels are fixed on the either side and other
6 panels are movable or sliding.
 The steel panels rotate around a hinge located at the front of the stadium, behind home plate. The
result is a dynamic, fan-shaped retraction that opens up from center field out until all panels are
stacked above seating areas along the baselines.

15. WORKING-Common concept on which almost all retractable roof work
Roofing Panels are adjusted over carriers (steel trusses) and these carriers roll over the steel rails
which are powered by DC motors. Thrust releasing mechanism is integrated into retractable roof
stadiums or we can say that it works on thrust releasing mechanism. Thrust is a force which drags
the machine. The best example of thrust is the movement of aircraft.
Minute Maid Park, Houston:

17. RETRACTABLE SEATING SYSTEMS
Retractable seating systems are tiers of seating that
fold away in to a space the depth of a single row.
They are most commonly used in multipurpose
spaces wheres eating is not always required, and
can be designed to be stored in situ or in a separate
location.
Retractable Seating in Basketball court
Retractable Seats

18. Applications:
Materials used
• Seat framesare manufactured from steel, which is then
galvanized or thermoplastic- coated to provide protection
against corrosion and wear
• To many existing venues are evolving into multipurpose environments. Its no longer
financially viable for a venue to cater to one event type, and they must be to accommodate
concerts, conventions and seminars, as well as different types of sporting events through
out the year.

19. FUNCTIONAL OPTIONS
Opening, AND closing functions
• Manual opening, which is ideal for smaller
units
• Integral power operation, which uses a
friction drive operated by an attached
pendant or wire less fob
• External power trucks, which are used for
very large venues with multiple retractable
units. Retracted SeatsUnretracted Seats
Retracted SeatsUnretracted Seats

20. ROGERS CENTRE
• Location: Toronto ,Canada.
• Previously known as The Toronto Sky Dome.
• Used for baseball and has the capacity for as
many as 54,000 fans.
• The roof opens in 21 minutes and the
stadium is 91% exposed.
• The roof structure area is 32,374 m2.
• Roof is composed of four steel-framed
dome shaped shells, which rest on a
reinforced concrete base.
• Roof is covered by 1.2 mm woven polyester
reinforced white PVC membrane.
ROGERS CENTRE

21.  Plenary Hall of Hyderabad international Convention Center
Some example in India :
 Retractable system used in Indian Residences

22. Why limited use in India?
Retractable roof that can cover the stadium and protect it from rainfall
so that precious time can be saved and along with it but…
• it is not economical.
• there wont be any impact of Moisture and weather on the Pitch and
henceforth impact of bowlers will be lost
• Stadium is not always completely filled with a full crowd.
CONCLUSION:
•An entire playing field moved to enhance the utilization of a stadium as well as the life of
the field itself.
•Retractable roof system are very useful in maintaining comfortable temperature in
buildings.
•A retractable roof system protects outdoor areas and help the owners to enjoy the
outdoors all year without worrying about the weather

23. SOME MAJOR MANUFACTORING COMPANIES
UNI-SYSTEMS, Minneapolis,United States
Bosch Rexroth, USA
VAHLE
Moog Industrial Group
Avant, china

24. REFERENCES
https://en.wikipedia.org/wiki/Retractable_roof
https://en.wikipedia.org/wiki/Sapporo_Dome
http://www.bloomberg.com/ss/06/08/wow_top10/source/4.htm
http://inhabitat.com/worlds-first-sliding-pitch-makes-tottenham-hotspur-stadium-fit-for-both-us-and-uk-football/
http://www.azcardinalsstadium.com/
http://www.uni-systems.com/files/broch_cardinals_stadium.pdf
http://www.uni-systems.com/files/broch_company_profile.pdf
http://old.seattletimes.com/sports/allstar/safeco/retr_roof.html
http://solutions.uni-systems.com/Specialty-Kinetic-Structures/retractable-flooring.html#sthash.ozB1iOXp.dpuf
https://pdfs.semanticscholar.org/2f16/974bb67830eb3faf34094302b091177576e1.pdf
https://en.wikipedia.org/wiki/Rogers_Centre
http://mercedesbenzstadium.com/

25. THANK YOU