Structures

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Structures
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Structures

• A structure is an arrangement of parts
• joined strongly together.
• Most objects are arrangements of parts, e.g.
• atoms, crystals, cells

Atoms / Cells
Crystals
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Structures
Golden Gate
There are many different types of structures in
existence Can you name some structures?
Eiffel Tower
Examples of structures include Buildings,
Bridges, Cranes, Chairs.
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Structures
What do you think contributes to strength in
structures?
This picture shows Buildings, a tower crane and
scaffolding
Tribal Home

• Factors that contribute to strength in
  structures.
• The strength of the material
• The shape of the parts
• The method used to join them together
• The manner in which they are arranged

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Structures

• There are many very strong structures to be found
  in nature.
• How many can you name?

Trees
Spiders Web
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Structures
Naturally strong features in useful designs
Bee honeycomb
Honeycomb floor mat
Mount Everest
Pyramid Egypt
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Structures

• Naturally occurring structures include
• A grass leaf
• A water lily
• A palm tree leaf
• Sea arch
• Car shell

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Structures
Honeycomb used as a core in sandwiched
structures, boards and flooring.

• Grass leaves have a honeycomb
• structure which, although very light,
• are also thick and strong.

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Structures
Water lilies have a web-like structure, which
grows from the centre to the outside of the Leaf
giving it strength.
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Structures

• Palm tree leaves,
• though light, gain their
• strength from thin sheets
• folded into corrugations.

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Structures

• Sea Arch.
• Coastal features, formed
• by weathering

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Structures
Shells provide shelter, and protect.
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Structures
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Structures
Frames are structures made from sections of
materials.
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Structures
A triangle is one of the strongest frame shapes
known to man. The implementation of this concept
in design is known as triangulation.
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Structures

• A strut is the part, which has compressive
  forces acting upon it.
• A tie is the part of a structure which has
  tensile forces acting upon it.

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Structures
Calculating Forces
The frame opposite supports a Mass of 60Kg. Pin A
in the sketch is in equilibrium. Calculate the
size of the forces acting on members B and C in
the frame.
In order to calculate the force of the Mass in
Newtons, the Mass must be Multiplied by 9.81N,
rounded to (10).Therefore force equals 600N.
Triangle of Forces diagram.
The force at B is calculated as 600 Cos 60
(600)(0.5) 300N
The force at C is calculated as 600 Sin 60
(600)(0.866) 519.6N
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Structures
Factor of Safety is used to provide a margin of
lee-way of flexibility over the theoretical
capacity of the item in question.