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A structure is a 3D shape made from different materials and parts.

Some can be simple to build, such as a wall. Others can be complex, or harder to build, such as a bridge or a building.

The strength of a structure can be affected by the materials it is made from and how its parts are connected together and supported.

Join Fran, Richard and Charlotte as they use triangles to strengthen a frame structure.

Brick and stone are popular, strong building materials. They can be placed on top of each other and joined together to make a structure.

Structures made from these materials are often made stronger by using:

• brick bonding - overlapping the edges of the stones and bricks as they are placed on top of each other
• buttresses - thicker walls near the bottom of the outside of a structure that form a triangle shape

Wood is often naturally strong and it can be strengthened further when needed to help build bigger and more rigid structures.

There are many reasons for using wood to build structures:

• it can be cut easily and made into different shapes and sizes

• it is lighter than other materials such as brick and steel

• it is affordable, many types wood are cheaper than other materials such as brick and steel

• it is a renewable material, as we cut down and use trees, more can be planted for future use

Structures made from metal can be bigger and stronger than those made of stone or wood. Steel is a very strong metal that is used to build tall buildings. Aluminium is a lightweight and cheaper metal.

Metal is often chosen as a building material instead of wood because:

• it is stronger

• it can be made into any shape

• it is more durable and will often last longer

Find out about these different techniques that can be used to strengthen a structure.

Triangulation

Triangles are the strongest shape. They hold their shape when weight is applied because the weight is spread downwards along their sides.

In complex structures, materials are often arranged into triangles – this is called triangulation.

This helps make a structure strong enough to support a heavy weight or to be built on a large scale.

Trusses

A truss is a frame structure made with triangles. Each triangle has beams that are connected and joined at the corners.

The beams work together and spread the load evenly across the whole structure, supporting the load and staying rigid and strong.

This lets truss structures carry heavy weight or reach across long distances.

Beams and columns

A roof needs to hold a lot of weight. It rests on columns and beams. Beams are pieces of material arranged horizontally. Columns are pieces of material that are arranged vertically.

Rain, wind and snow can add heavy weight to a house roof, so columns and beams are used to help evenly spread the load and remain strong.

See if you can spot the features of different structures in this activity.

Take this quiz to find out what you know about strengthening structures.