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Presented by:
~ Nor Jauriah bt Othman
~ Fairuz Nadia bt Salim
DESIGN, INNOVATION AND
INVENTIONS
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Example the shapes of objects that
are stable
Trusses
Beam bridges can span
a greater distance with
a thicker beam. But
there is a limit, becausetoo thick a beam will
sag into the river. An
alternate solution is to
build a beam oftriangles, a "truss,"
which is much lighter
than a beam of similar
thickness. A truss is
extremely strong and
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The Arch The arch is used in
tunnels, bridges andmany other structures
because is can bear agreat deal of weight(load). The arch formtransforms the verticalpressure of thestructure above intolateral(sideways) pressure.The Romans used the
arch in many of theirbuildin s.
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The Flying Buttress
The force is
transferred to the
buttress which helps
support the building
so it will be able to
support the roof
without collapsing
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Burj Dubai Dubai,
United Arab Emirates
Taipei 101 Taipei,
Taiwan
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Serpentine GalleryPavilion 2006
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Factorsaffecting the
stability of astructure
Height- The lower the structure, the more
stable the object is
- P is more stable because it isshorter
Base area- The larger the base area, the
more stable the objects is
- L is more stable because it haslarger base area.
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Importance of stability Racing cars are built
low. They have widetyres. The tyres are setwide apart to give thecar a large base area
Some furnitures aremade stable by havingbroad legs that are set
wide apart
Some appliances aredesingned with a largeand heavy base
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Factors that affect the strength of a
structure
The types of materialsused to build it
1) Steel wires - bundledtogether to make
suspension bridge cablesare one material strong intension
2) Stone - strong incompression.
- Ex: The Egyptianpyramids, which are madeof stone blocks, someweighing over a tonne.
The blocks on the bottomsupport the weight of the
How the structuredare placed
- A structure whichcracks, breaks orcollapses easily is notstrong
- A strong bridge is notonly able to stand itsown weight, but also be
able to stand strongwind and vibrations
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A Structure that
withstand demanding
conditions of the
Earth
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WHY EARTHQUAKE?
Most of the damage we associate with
earthquakes involves human-built structures:
people trapped by collapsed buildings or cut off
from vital water or energy supplies
It might seem obvious to say that earthquakes do
most of their damage by shaking the ground.
When the ground beneath a building shakes, it
makes the building sway as the energy of a
quakes wavesmoves through it.
Do you think that a skyscraper would be more
dangerous than a smaller office building?:
http://www.exploratorium.edu/faultline/basics/waves.htmlhttp://www.exploratorium.edu/faultline/basics/waves.html8/14/2019 Topic 2 Stability of Structure
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The taller a structure, the more flexible
it is. The more flexible it is, the less
energy is required to keep it from
toppling or collapsing when the earth's
shaking makes it sway.
Because shorter buildings are stiffer
than taller ones, a three-story
apartment house is considered more
vulnerable to earthquake damage than
a 30-story skyscraper.
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Example
The TransAmerica pyramid inSan Francisco is famous forits architecture: a wide base
that narrows as it goes upincreases the buildingsstability.
A network of diagonal
trusses at its base supportsthe building against bothhorizontal and verticalforces.
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INTRODUCTION
The Transamerica Pyramid is San
Francisco's tallest building.
The Pyramid has 49 stories and a
212 foot spire. The height from
the apex to the ground is 845
feet. The base width is 175 feet.
The pyramid is flanked by a set of
structures that look like wings.
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The Uniqueness of the Building
The unique structuralfeature of this taperedbuilding is the truss
system above the firstfloor.
The photos are courtesyof the EarthquakeEngineering ResearchCenter, University ofCalifornia, Berkeley.
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The Truss System
The truss system supports
both vertical and horizontal
loading.
The building is carefullyengineered to take large
horizontal base shear forces.
The overhead X-bracing
resists torsional movement of
the building about its vertical
axis.
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Roller coaster--one of
the scariest structures
around. But scary as
they are, coasters arebasically just bridges
with incredibly steep
hills. Coasters'
triangular trusses makethem extremely strong
structures.
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REFERENCE
Building that withstand earthquake
http://www.exploratorium.edu/faultline/damag
e/building.html
The TransAmerica
http://www.vibrationdata.com/earthquakes/Pyr
amid.htm
http://www.exploratorium.edu/faultline/damage/building.htmlhttp://www.exploratorium.edu/faultline/damage/building.htmlhttp://www.vibrationdata.com/earthquakes/Pyramid.htmhttp://www.vibrationdata.com/earthquakes/Pyramid.htmhttp://www.vibrationdata.com/earthquakes/Pyramid.htmhttp://www.vibrationdata.com/earthquakes/Pyramid.htmhttp://www.exploratorium.edu/faultline/damage/building.htmlhttp://www.exploratorium.edu/faultline/damage/building.htmlTop Related