Page 32 - English for Construction 2
P. 32

Properties      of   materials


                      Speaking  1   Work n pairs. Imagine  you  are  going  to  build  a  driveway  to  a house.  Think
                                         i
                                    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.
                                        t
                                    List he  materials  you  hear.
                                    stones,  ...
                                 3  Here are some adjectives  (in italics) hat the  contractor  uses o  describe  the
                                                                                         t
                                                                    t
                                    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.
                                         i
                                                            t
                                                                                i
                                    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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