Page 32 - English for Construction 2

Properties of materials

Speaking 1 Work n pairs. Imagine you are going to build a driveway to a house. Think
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about the materials and the different layers you will need. Give reasons for your
choices. Use these sketches to help you.

surface

binder

base

sub-base

sub-grade

Listening 2 K ^ X c I Listen to a contractor describing two types of driveway construction.
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List he materials you hear.
stones, ...
3 Here are some adjectives (in italics) hat the contractor uses o describe the
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materials. Write he opposite of the adjectives. Then listen again and check
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your answers.
1 a firm surface
2 coarse sand or grit
3 a strong sub-base
4 tough edging
5 an attractive appearance
6 a rough texture
4 E ! 3 H Listen to a contractor talking about the key properties of asphalt.
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Make notes on what he says about he following.
penetration value - tells you how hard or soft the asphalt is;
depends on the climate
1 cutback
2 porosity
3 noise reduction
4 reflection

5 Match these words to the key properties in 4. Listen again and check
your answers.

cure glare hard sound water

Speaking 6 Work n pairs. Discuss w h y he properties in 4 are mportant in building roads.
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Penetration values tell us how hard or soft the asphalt is. I think harder asphalt
lasts longer, but in hot climates hard asphalt cracks.

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