Goongoongup Bridge replaced the 1932 built timber Bunbury Bridge which was demolished in 1996.[3] It had replaced the original 1893 structure that was damaged by floods.[1]
The double-track concrete bridge is 407 metres (1,335 ft) long and is supported by eight piers. A dual-use pedestrian/cycle pathway is beneath the main deck.
A six-lane road bridge Windan Bridge opened in 2000 and is situated parallel and 2 metres (6 ft 7 in) upstream from Goongoongup Bridge.
Repairs
Abutment repair work in April 2012
In 2002, movement of soil on the eastern end of the bridge was detected.[4][5] Displacement of 140 mm (5.5 in) on the abutments was measured and engineering reports predicted the displacement would be 300 mm (12 in) by the end of the century and that the abutment piles would yield in 10 to 20 years.
^Prof. Serge Leroueil. "Goongoonup Railway Bridge, Australia". Ottawa Geotechnical Group. ...In 2002, a displacement of 140 mm (5.5 in) of the eastern abutment was measured and an independent report predicted at that time that it would be 300 mm (12 in) by the end of the century and that the abutment piles would yield in 10 to 20 years. The owner of the bridge, the Public Transport Authority, involved experts in structural and geotechnical engineering as well as an engineering firm to examine the situation. First assessment showed several current or potential problems: the bearing capacity of the abutment piles could be exceeded; the abutment bearings were at their limit; the concrete piles of the approach structure were cracked in their upper part and their capacity had to be examined; the raked piles of the closest pier to the abutment were subjected to soil settlement and could have yielded.
^Stewart, D.P. and McInnes, D.B. The impact of lateral soil displacements on the Goongoonup rail bridge, Perth, 8th ANZ Conference on Geomechanics, Canberra, ACT, Australian Geomechanics Society, 1: pp 345-351 (1999)
