Environmental Engineering Structure Case Study 2022

Introduction
This report is a case study on one specific civil or environmental engineering
structure or project in a local area. This technical report will entail personally
conducted research, detailed research from internet websites along with data
from recent articles and government documents, all these sources will be
provided in the bibliography section.
This report is centred on the Sydney Harbour Bridge which is located in the
state of New South Wales (NSW) in Australia. The Sydney Harbour Bridge is a
structure that was built in 1932 and serves as a connection between the City
and the Northern Suburbs.
This report will also delve deeper into the components of the Bridge’s history
covering the reasons for construction along with some controversy behind the
designs. The properties of the design and its layout will be outlined along with
the cost estimation for the structure. The Sydney Harbour Bridge also requires
significant annual investments into its maintenance and this procedure will
also be covered. Many factors must be considered when civil engineers and
architects decide to take a project including the proportions, material choice
and the surrounding environment and many more which will be covered in
detail later in this engineering case study report. The Sydney Harbour Bridge
has many components which come together harmoniously in order to provide
the people of the city with such a spectacle to view and also allows for an
easy commute across the harbour. These components are categorized into
the Bridge’s superstructure and substructure, which will be broken down and
discussed in detail under their corresponding sections. The ideas behind the
design and inspiration of the Harbour Bridge were not straightforward and
there was much more behind the construction of the bridge than what meets
the eye. Finally, the safety of the bridge is one of the most crucial
components of a civil structure and cannot be looked over without being given
its own section. Although the bridge has been standing for close to 100 years,
improvements can always be made in order to ensure the long life and
sustainability of a structure which will be discussed with recommendations.
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Table of Contents
History.......................................................................................................................... 4
Properties, Layout and Cost......................................................................................... 5
Maintenance................................................................................................................. 6
Vision and Aesthetics................................................................................................... 7
Superstructure............................................................................................................. 9
Substructure............................................................................................................... 12
Design and Planning................................................................................................... 14
Construction............................................................................................................... 15
Safety and Testing..................................................................................................... 16
Recommendations for Improvement..........................................................................17
Bibliography............................................................................................................... 18
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History
The Sydney HarbourBridge is a steel tied arch bridge, situated in port Jackson
providing a link between Sydney and the suburbs which are on the northern
side of the Harbour. The plans for the bridge were presented by a civil
engineer named John Bradfield, who worked for the NSW Department of Public
Works, in 1912. In the initial plans, John had submitted the option of
constructing either a suspension or a cantilever bridge and had envisioned it
as an essential part of an electric railway system for Sydney. After a year
John’s cantilever design was accepted and he was also appointed as the lead
for the project. However,due to World War I the bridge construction was
delayed until further notice. It wasn’t till 1922 that the funds were finally
available to start construction of the bridge, in this time many advancements
were made in the industry of steel that it was viable to construct an arch
Bridge.
With the plans altered, the contract for construction was given to an English
company Dorman Long and Co, who had appointed Sir Ralph Freeman for the
designs. The design was approved for an arch bridge to connect Dawes Point
on the South with Milsons Point at the Northern end. Here a steel arch bridge
was the preferred choice due to its cost efficiency in comparison to a
cantilever bridge, while also being able to handle significantly greater loads.
Finally, after the approval of the arched steel design, construction had begun
under Bradfield's supervision in 1924. Due to the deep waters of the Harbour,
the use of temporary supports in the middle were impractical and difficult to
deploy. So, the bridge was constructed from both banks and met in the middle
in 1930, however, the bridge was not officially open till the 19th of March
1932. There is still some controversy behind the design of the bridge, despite
the initial submission of the design being made by Bradfield, Freeman
considers himself as the true designer of the Sydney Harbour Bridge and this
claim is supported by some authorities, but this controversy was never fully
resolved. (Sydney Harbour Bridge | Dimensions, Location, History, & Facts |
Britannica, 2022)
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Properties, Layout and Cost
The Sydney Harbour Bridge is a steel tied arch built in 1932, and till today
carries rail and road traffic along with pedestrians across from the Sydney
CBD to the North Shore. The Sydney Harbour Bridge was nicknamed the “Coat
hanger” due to its arched design depicting that of a coat hanger. The
structure is 1,149 m long and measures 48 meters wide and is also the
world’s tallest arched bridge reaching a height of 134 m from the water to its
peak, this bridge also comes in at 6th in the world for longest spanning bridge.
(Institution of Civil Engineers (ICE), 2018) The design for the bridge was
actually greatly inspired by the shape of the Hell Gate Bridge in New York. The
Harbour Bridge is an essential part of hundreds of thousands of people’s daily
commute, as the Harbour Bridge houses 7 vehicle lanes, one 24-hour bus
lane, two train lines, one footpath and a cycle path. (A short history of the
Sydney Harbour Bridge., n.d.)
This structure is an icon of Australia and is also one of the most famous
images of Australia, as this is a distinguishing feature of this country movies
use a shot of this bridge to set the scene frequently. At the time of
construction the Bridge cost 10 million Pounds to build which would come to
around 1.5 billion AUD in today economy.
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