IELTS Reading Formula
(MAXIMISER)
117
IEL TS Reading (Activity
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Flowchart com�letion
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Building the Sydney Harbour Bridge:
One of the world's most recognisable and admired engineering
structures is the Sydney Harbour Bridge.
Its great arch, soaring above the blue water of Sydney Harbour,
dominating the skyline, is a truly impressive sight. How was the bridge actually built? The citizens of the
era, who watched its progress over six years of construction, would have
been able to describe the
process in detail, but we in the modem age may not quite appreciate how it was done. It is necessary to
understand the basic structure first. The main components are: * four decorative pillars or pylons (hollow
structures which actually carry no weight) * a
-
soaring double arch, formed of higher and lower sections
known as chords* a series of connected cross girders, supporting the busy roadway*
two rows of
elegant vertical hangers, linking the arch and roadway.
It might be thought that the pylons came first, but in fact each of
the arches was built first, in sections.
During construction, each new chord was attached to the previous one by cables secured to the ground.
As each new chord was added, the arches could be seen cantilevered out into the air above the water.
Each side of the bridge was not started at the same time - the southern part was started first and the
northern part followed seven months later, so any problems that became evident could be rectified. Each
side of the arch was added to until they each rose into the air to the point of meeting. Sitting on top of
the two top arches throughout were the two creeper cranes that lifted workers and essential materials
from pontoons on the water below.
The final point of the arches meeting was achieved in 1928 when first
the lower arch and then the
upper arch were manoeuvred and then riveted into position. After this came the hazardous operation
needed to create the roadway. First, pairs of hangers, up to 60 metres long,
had to be lifted up one by
one from pontoons by the cranes (with workers riding them up into position) and then attached to the
arch. Once each pair of these was safely installed, a 100-ton cross girder was lifted and attached to the
hangers so that the road and railway could be constructed. Only after all this
was complete were the
pylons constructed and then faced with granite by Italian stonemasons. In early 1932, the road and
railway bridge was tested for strength by driving 30 trains onto the track. Finally, on 10 March 1932, in
front of dignitaries and the general public, the big wait was over and the bridge was officially opened.
Complete the flow chart below. Choose NO MORE THAN THREE WORDS for each answer.
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