1 e bil - structures - 2nd part - types of structures

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Types of structures. 2nd part of the unit about structures in Technologies for 1st year ESO

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1

STRUCTURES2nd part

Types of structures

Technologies1st year ESO

Types of structures

1. MASS STRUCTURES

1. Mass structures

They can be made by, piling up or forming similar materials into a particular shape or design.

Sand castles, dams and brick walls are manufactured mass structures.

Advantages: They are hold in place by their own weight. Losing small parts often has little effect on the overall strength of the structure.

Types of structures

2. FRAME STRUCTURES

2. Frame Structures

They have a skeleton of strong materials, which is then filled and covered with other

materials, supporting the overall structure. Most of the inside part of the structure is

empty space.

Buildings made of steel beams and columns are an example of frame structures.

Sometimes the columns and beams are made of reinforced concrete instead of steel.

Concrete is a mixture of cement and stone

aggregate and mixed with a small amount of

water. When steel bars are placed in concrete,

the composite material is called reinforced

concrete. It resists compression and bending.

Types of structures

2. FRAME STRUCTURES

Types of structures

3. TRUSSES

3. Trusses

Trusses are frame structures formed by triangles.

The triangle is the most rigid frame structure and many complex structures are based

on triangles. The technique used in these type of structures is called triangulation.

When forces are applied to a simple four-sided structure, it can be forced out of shape. A structure which behaves in this way is said to be non-rigid

By adding an extra bar the structure can no longer be forced out of shape, and is said to be rigid.

The effect is known as triangulation

Types of structures

3. TRUSSES

Types of structures

4. SHELL STRUCTURES

4. Shell Structures

Structures, which keep their shape and support loads, even without a frame, or solid mass material inside, are called shell structures. These structures use an outer layer of material to provide their strength and rigidity. The shape of a shell structure spreads forces throughout the whole structure, which means every part of the structure supports only a small part of the load, giving it its strength.Examples include: egg cartons, water containers, gas tanks and cars

Types of structures

5. SUSPENSION STRUCTURES5. Suspension structures Suspension structures are those with horizontal planes (road decks, roofs, and even floors) supported by cables (hangers). Suspension bridges are good examples of these structures. In these bridges, cables suspended via towers hold up the road deck.

Types of structures

6. VAULTED STRUCTURES6. Vaulted structuresVaulted structures are those formed with arches. They are usually used to provide a big space with a ceiling or roof. The weight of the ceiling is conducted through the vault into the pillars (or columns) that are supporting it, and from those pillars into the foundation of the building.

Different shapes in the vaulted structures have been used through history and depending on the different cultures.

Types of structures

7. GEODESIC STRUCTURES7. Geodesic structuresGeodesic structures (usuaslly called geodesic domes) are a kind of shell structures in which the shell is formed by polygons (usually triangles).

Types of structures

Think about the type of the structure of the following buildings/objects and what advantages it has

Mass structure

Mass structure

Mass structure

Vaulted structure

Vaulted structure

Vaulted structure

Vaulted structure

Frame structure

Frame structure

Frame structure

Frame structure

Shellstructure

Shellstructure

Shellstructure

Trusses

Trusses

Trusses

Suspension structure

Suspension structure

Suspension structure

Which type of structure is each of the following

pictures?

Take it down in your notebook