SYDNEY HARBOUR BRIDGE FORM ACTIVE, ARCH STRUCTURE BOOK CASE STUDY – LONG SPAN

Location : Sydney , New South Wales , Australia

Designer : John Bradfield

Total length : 1,149 m

Width : 49 m
Height : 134 m The construction on the northern side was
Longest span : 503 m The half arches were secured by wire ropes, kept 7 months behind the southern side.
Clearance below : 49 m mid-span anchored in inclined U-shaped tunnels cut Reason was that if any problems were
Construction begin : 28 July 1923 into the rock. Anchorage consisted of 128 wire encountered on the southern side steps could
Opened : 19 March 1932 ropes of 70 mm diameter, about 366 m long. be taken to remedy them on northern side.

The arch is composed of two 28-panel arch trusses.

Load diagram
The way this bridge transfers dead/live and environmental loads to the ground ,the loads acting
upon the crossing (shown above in blue), this crossing begins to bend under the weight of the
loads. When the crossing begins to bend this causes the columns (green) to be in tension and
take the weight of the crossing. As the columns get pulled this in turn pulls down the steel frame
structure (black). From here the steel frame structure distributes the weight along its internal Joining the cantilevers changed the structure into a self-supporting 3hinged arch. This
structure until it gets to the cement columns (red). From here the cement columns which are was a temporary condition allowing the bottom chord to take the thrust of the arch while
buried deep into the ground the top chord was completed

• The steel work alone weighs 52,800 tones and its held together by 6 million
rivets - each one driven in by hand.
• Also commonly known as Coathanger bridge ,opened in 1932 i.e 88 years
ago. Taking eight years to construct, it was also nicknamed 'the Iron Lung
because of the 1,400 jobs it provided during The Great Depression
• Concrete used for bridge 95,000 cubic metres. 3 members were used to close the open triangle at the
• Painting is the major maintenance work . The steelwork of the bridge that A temporary hinge arrangement was attached to the ends
needs to be painted is a combined 485,000 m2 of the bottom chords together with the steel spike to align crown. center post maintains the depth of the arch truss at
the two halves. When the ends of the cantilevers met the the top of the bridge by supporting the large top chord
The bridge climb is a must do activity . Riveting. temporary crown unit formed a structural hinge members. After the central post was placed , the 2 top
chords completed arch truss work.
The vertical hangers were
attached to the arch, and these
were then joined with horizontal
crossbeams. The deck for the
roadway and railway were built
on top of the crossbeams, with
the deck from the center of arch.

• At each end of the arch stands a pair of 89 m high

concrete pylons, faced with granite.
• The bridge carries 8 lanes of traffic. • Pylons are the architectural feature of the bridge
• North/South railway lines. and harmonized with the lines of arch.
• A temporary settlement at Moruya, where they
• Pedestrian walkway on the East side.
quarried around 18,000 m3 of granite stonemasons
• Cycle way on the west side. cut, dressed, and numbered the block for the pylon.

SINHGAD COLLEGE OF ARCHITECTURE , PUNE FOURTH YEAR B.ARCH ,DIV - A , 2020-21 SUBJECT:- ABTS SEM-VII AISHWARYA AWCHAR ROLL NO.:-04