Structures

Structures

What can you see here?

IDENTIFICATION EXERCISECan you identify the following structures?

IDENTIFICATION EXERCISE   1. Match each building with the corresponding fact and country.2. Differentiate between the present and past tense.

Building

Eiffel tower

Taj Mahal Statue of Liberty 

Big Ben Guggenheim Bilbao 

Facts

It was a present from France.

It was made for the Universal Exposition of 1889. It is the largest four-faced chiming clock in the world. It was built as a masoleum.   

It is covered in titanium panels.

Country

Spain

France

U.S.A

United Kingdom

India

STRUCTURES

• Why do we need bridges?•  Could you think of other kinds of structures?• Do you see any structures in the class?• Could you think of any structures that you use every day?

 DEFINITION OF STRUCTURE

A structure is a group of elements that can support weights without breaking or deforming.

PROPERTIES OF A STRUCTURE

RIGIDITY-A structure maintains its form

STABILITY-A structure cannot turn over.

RESISTENCE-A structure doesn't break easily. 

Types of structures

We can find different kinds of structures in our surroudings.  Structures created by nature are called natural structures.

E.g: Skeletons, rock formations, shells of an animal

Types of structures

Others have been designed and built by man to meet their needs during their evolution. These man-made structures are called artificial structures.  The most common examples of such structures are bridges and buildings.

STRUCTURAL ELEMENTS

Column  - A column is a vertical element that has to support the weight of a structure.  It transfers weight to the ground.

GRAMMAR REVIEW-When do you use have to?

STRUCTURAL ELEMENTSBeam- A beam is a horizontal element that has to support the weight of a structure.  It transfers weight to a column.

STRUCTURAL ELEMENTS

Brace-  A brace is an element that improves the rigidity of a structure.

STRUCTURAL ELEMENTS

Arch- An arch is an element that transfers weight to other structural elements, like columns and beams. 

Forces in Structures

A structure must be able to support, besides its own wheight, other forces and external loads acting on them.  http://www.galileo.org/tips/structures/forces.htmlThese forces are: TensionCompression

Flexion

Torsion

Shear

TENSION FORCES

Forces which cause a member to "stretch".

Compression Forces

Forces than can cause a member to be "squashed".