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Garratt Road Bridge consists of two adjacent bridges over the Swan River, linking the suburbs of Bayswater and Ascot in Perth, Western Australia. The upstream bridge was built in 1935, while the matching downstream bridge was built in 1972.〔 〕 The site was significant prior to the construction of Garratt Road Bridge – it featured in Aboriginal mythology, and was in the near vicinity of 1880s bridges for pedestrians and trains. From that time there were various proposal to provide a vehicular crossing between Bayswater and Bassendean. Interest peaked in 1928, but plans were delayed due to the Great Depression. The first bridge, designed by Main Roads Chief Engineer Ernest Godfrey, was constructed in 1934–35. It allowed two lanes of traffic to cross the Swan River, alongside pedestrians on an adjacent footbridge. Increasing traffic volume lead to the bridge being widened by in 1962. By the end of that decade, a second bridge was being planned to cope with rising levels of congestion. It was constructed during 1971–72, but with only a 40-year design life as it was expected to be redundant once the planned Beechboro–Gosnells Highway (modern-day Tonkin Highway) opened. From the 1970s, Main Roads has maintained the bridges with procedures that vastly extended the bridges' lifespans, including concrete overlays on the decks, and retrofitting of steel girders. The heritage value of the structure was recognised in 1998, and Garratt Road Bridge was included in the City of Bayswater's Municipal Heritage Inventory. Eleven years later, in 2009, it was added to the state heritage list, and a permanent entry was given on 23 March 2010. ==Description== Garratt Road Bridge consists of a pair of bridges across the Swan River, between Bayswater and Ascot. The upstream bridge, from 1935, carries southbound traffic, pedestrians, and two pipes, while northbound traffic travels on the 1970 downstream bridge. Both bridges are predominantly constructed from timber, and feature "timber piles driven into the river bed linked with timber cross bracing and double beams top and bottom and then spanned by timber logs which in turn support the wooden decking". The original bridge is at a lower height, and some of its beams have been replaced by Rolled Steel Joists. While both bridges have modern steel safety rails, the original white-painted wooden rail is still present along the pedestrian path. The original bridge has approximately 38 spans over 37 piers, along a length.〔 〕 Main Roads Western Australia maintains and controls Garratt Road Bridge. The road is designated Highway H37, while the bridges are designated Structure Number 950 (upstream) and Structure Number 952 (downstream). The original bridge has 38 spans over a length of , a width of , and a deck area of . The road width is , while the footpath width is . The newer bridge has similar measurements: 38 spans over a length of , width of , deck area of , and road width of . The longest spans of each bridges are in length. Garratt Road Bridge is the longest timber bridge still in existence in Western Australia. It may have been the longest ever built in the state,〔 〕 and the downstream bridge was probably the last wooden bridge to be built in Perth. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Garratt Road Bridge」の詳細全文を読む スポンサード リンク
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