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Materials Lab

Forces Lab | Materials Lab | Loads Lab | Shapes Lab

About This Lab
This lab simplifies the real-life properties of a selection of materials, in order to illustrate key concepts.

Intro/Instructions
What you build a structure out of is just as important as how you build it! Different materials have vastly different properties. Click on a material at left to find out more about it, and put it to the test.

Wood Properties
Type: Spruce (softwood)

Wood Pros+Cons
Strengths: Cheap, lightweight, moderately strong in compression and tension
Weaknesses: Rots, swells and burns easily

Wood Applications
Bridges, houses, two- to three-story buildings, roller coasters
Example: Son of Beast -- Cincinnati, Ohio

Wood Compression Message
You squeezed this block easily, but it took a lot of effort to make it break. Wood is cheap and pretty strong in compression. That's why people build houses out of wood!

Wood Tension Message
It wasn't easy to break this block of wood because wood is strong when you pull it in the direction of its fibers. It would have been three times easier for you to break this block if you'd stretched it from the top and bottom, across the direction of its fibers.

Plastic Properties
Type: High-strength plastic fabric Ingredients: Long chains of molecules

Plastic Pros+Cons
Strengths: Flexible, lightweight, long-lasting, strong in compression and tension
Weaknesses: Expensive

Plastic Applications
Umbrellas, inflatable roofs over sports arenas
Example: Georgia Dome -- Atlanta, Georgia

Plastic Compression Message
Compared to steel, you squeezed this plastic block easily, but it took a lot of effort to make it break. The long chains of molecules that make up plastic can be pulled and pushed in many directions without failing.

Plastic Tension Message
You stretched this plastic pretty far before it finally broke. The long chains of molecules that make up plastic can be pulled in many directions without snapping. That's one of the reasons why circus tents are made of plastic fabric!

Aluminum Properties
Type: Aluminum alloy Ingredients: Aluminum with magnesium & copper

Aluminum Pros+Cons
Strengths: Lightweight, doesn't rust, strong in compression and tension
Weaknesses: Expensive

Aluminum Applications
Airplane wings, boats, cars, skyscraper "skin"
Example: Petronas Towers -- Kuala Lumpur, Malaysia

Aluminum Compression Message
It was pretty hard for you to break this aluminum block. That's because the magnesium and copper inside this block makes it almost as strong as steel!

Aluminum Tension Message
It wasn't easy to break this aluminum block. That's because aluminum, when combined with metals like magnesium and copper, is almost as strong as steel!

Brick Properties
Type: Ordinary brick Ingredients: Burned clay

Brick Pros+Cons
Strengths: Cheap, strong in compression
Weaknesses: Heavy, weak in tension

Brick Applications
Walls of early skyscrapers and tunnels, domes
Example: Original Thames Tunnel -- London, England

Brick Compression Message
You had to push this brick very hard to make it crumble. Bricks are very strong in compression. That's why early houses were made of brick!

Brick Tension Message
You pulled this brick apart easily! That's because bricks are very weak in tension.

Concrete Properties
Type: Fine-grain concrete Ingredients: Cement, water, small stones

Concrete Pros+Cons
Strengths: Cheap, fireproof and weatherproof, molds to any shape, strong in compression
Weaknesses: Cracks with temperature changes, weak in tension

Concrete Applications
Early arch bridges and domes
Example: Pantheon - Rome, Italy

Concrete Compression Message
You had to squeeze this concrete block really hard to make it break. That's because concrete is very strong in compression.

Concrete Tension Message
You pulled apart the small stones and cement in this concrete block easily. That's because concrete is weak in tension.

Reinforced Concrete Properties
Type: Fine-grain concrete with high-strength steel Ingredients: Steel bars hidden in concrete

Reinforced Concrete Pros+Cons
Strengths: Low cost, fireproof and weatherproof, molds to any shape, strong in compression and tension
Weaknesses: Can crack as it cools and hardens

Reinforced Concrete Applications
Bridges, dams, domes, beams and columns in skyscrapers
Example: Hoover Dam - Nevada/Arizona border

Reinforced Concrete Compression Message
You had to squeeze this block really hard to make it break. That's because concrete and steel are both very strong in compression.

Reinforced Concrete Tension Message
It was hard to pull this concrete block apart because the steel bars inside make it very strong in tension. That's why some of the tallest skyscrapers in the world are made of reinforced concrete.

Iron Properties
Type: Cast iron Ingredients: Iron with lots of carbon

Iron Pros+Cons
Strengths: Molds to any shape, strong in compression
Weaknesses: Weaker than steel in tension, breaks without warning

Iron Applications
Arch bridges, cannons, historic domes
Example: Iron Bridge - Shropshire, England

Iron Compression Message
It wasn't easy for you to squeeze this cast-iron block. Cast iron is strong in compression. That's why early arch bridges were made of cast iron.

Iron Tension Message
It was easy for you to pull this cast-iron block apart. That's because cast iron is brittle -- it snaps without warning.

Steel Properties
Type: High-strength steel
Ingredients: Iron with a touch of carbon

Steel Pros+Cons
Strengths: One of strongest materials used in construction, strong in compression and tension
Weaknesses: Rusts, loses strength in extremely high temperatures

Steel Applications
Cables in suspension bridges, trusses, beams and columns in skyscrapers, roller coasters
Example: Sears Tower - Chicago, Illinois

Steel Compression Message
You had to push extra hard on this steel block to make it bend and break. Steel is stronger than any other material in compression. That's why engineers choose steel beams and columns to support most skyscrapers.

Steel Tension Message
You had to pull this block incredibly hard to make it break because steel is stronger than any other material in tension. That's why the cables in the Golden Gate Bridge are made of steel.

Flash version of this lab


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