Page 37 - 6748

makes it a free movement floor, where vehicles can run anywhere on it. But on the
manufacturing process drawings, it shows precisely specified routes for these automated
vehicles. So, technically, it should be a defined movement floor, where you can just have a few
narrow lanes for the vehicles, which are superflat, and then the rest of the slab is just laid to
normal tolerances.
Lewis: Right. So you're questioning the extra cost of doing everything superflat?
Mei: That's the main thing, yeah. The other thing is quality. To get the best finish on these
superflat floors, it's better to lay narrow widths of slab in fairly long lengths. So, ideally, you
want lanes, rather than big, wide areas.
Lewis: OK. But maybe they want everywhere to be superflat so they can change the layout of the
production line in the future.
Mei: Possibly. But even if they want to do that, the surface can always be modified at a later
date. It’s a thick slab, so there's nothing to stop them grinding a layer off the top. In fact, we
could increase the depth of the steel reinforcement slightly when we pour the slab, so there's
some extra thickness of concrete over it. So, if they did want to grind a thin layer off a section in
future, they wouldn't have problems with shallow cover.
Lewis: Right. Well let’s look into an alternative design for a defined movement floor.

b Complete the following table using the words in the text in Exercise 6b.
Name of dimension Large dimension Small dimension
1 What's the ? Is it ? Is it short?
2 What's the width ? Is it ? Is it narrow?
3 What's the ? Is it high ? Is it low?
4 What's the thickness? Is it ? Is it thin?
5 What's the ? Is it deep ? Is it shallow?

c Mei has done a revised drawing for the floor slab. Read the extract from her email about
the new design and complete the message using the correct form of the words in Exercise
7b.
To: Lewis Rosas
Subject: Revised floor slab drawing
Please find attached a revised drawing for the floor slab, now reconfigured for defined
movement. In order to accommodate guided vehicles 1 080mm (1) (as
specified by the client) we propose a standard (2) of 1 280mm for each
superflat lane. At 14.5m, the (3) of the longest lane on the network is within
the maximum slab run that can be cast in a single concrete pour, thus avoiding construction
joints on straight runs. On curved sections, a standard 8.5m turning radius is used, as per the
guided vehicle manufacturer’s recommendations. In order to allow for the eventuality of future
grinding, we have located the top layer of reinforcement 10mm deeper below the slab surface.
This additional (4) has not, however, been added to the overall slab
(5) , which remains 275mm. The reinforcing bars also remain in 12mm
diameter. As a result, the levels of wall-mounted process installations - many of which need to
be fixed at a precise (6) above finished floor level - are unaffected.

d Which two words in the email relate to circles? What aspects of a circle do they
describe?
8 The manufacturing plant in Exercise 7 will be built from a steel frame. The vertical
elements of the frame will be Universal Columns (UCs). Look at the section of a UC. In
pairs, describe the different dimensions that define a UC profile by explaining what the
letters on the section refer to.

35