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:''For the bridge in Grafton, NSW, see "Grafton Bridge, NSW."'' Grafton Bridge is a road bridge spanning Grafton Gully in Auckland, New Zealand. Built of reinforced concrete in 1910, it connects the Auckland CBD and Karangahape Road with Grafton. It spans about 97.6 metres (320 feet), rises 25.6 metres (84 feet) above the abutments to a height of around 43 metres (142 feet) over the gully. The bridge is listed by the New Zealand Historic Places Trust and on the IPENZ Engineering Heritage Register. In a 2006 poll of 600 alumni of the University of Auckland School of Engineering, the bridge was third in the list of New Zealand engineering achievements, after Manapouri Power Station and ''Black Magic''. Since 2009 the bridge has formed a core part of the Central Connector public transport route between the CBD and Newmarket, and is closed to private vehicles during the day. ==History== Designed by engineers R. F. Moore and Karl Rosegger Agster for the Ferro-Concrete Company of Australasia, the bridge's completion was supervised by the city's engineer, W. E. Bush,〔 The bridge was built between 1908 and 1910 and was the third bridge to cross Grafton Gully. The first, built in 1884, was a cable-stay pedestrian bridge from the bottom of St Martins Lane to Bridge Street in Grafton (the current bridge connects Karangahape Road and Grafton Road). Designed by the City Engineer Edward Anderson, the first bridge proved to be comparatively unstable, at least towards the end of its life when it would appear that maintenance was not kept up. By the time it was approaching 20 years old police were stationed at each end after rugby matches to ensure rowdy crowds did not cause it to wobble alarmingly by jumping or stamping on it.〔 In 1904 a report showed it was not only was it beyond repair but that it was lucky it hadn't collapsed. It was immediately closed and supplemented by a temporary bridge of quite simple design at the bottom of the gully. The old disused bridge stood until 1906. Discussions within Council over the design of the new permanent bridge dragged on for years requiring a rebuild of the temporary bridge and the construction of long flights of wooden steps from St Martins Lane and Bridge Street to make pedestrian access easier. There was conflict over whether any new bridge should be another pedestrian bridge or one that would take vehicle traffic as well. Eventually the decision to build a road bridge was taken. The current bridge was championed by the Mayor Arthur Myers, who advocated for it to be twice as wide as built. Even in its narrower form it was to cost £31,918, resulting in it being called "Myers' Folly" by many at the time, but was also seen to symbolise a commitment to a 'Greater Auckland', indicating leadership in technology development.〔 Many people maintained that the city would never get big enough to warrant the cost of so large a piece of engineering. Conversely Myers predicted that the population of Auckland would double in the next two decades, and he was proved correct. Built of reinforced concrete by the Ferro-Concrete Company of Australasia Ltd, it is believed to have been the biggest arch bridge span of that type at that time. It utilises large 'false piers' on each side of the central arch, which give the appearance of strength in the classical masonry style, but are not required to be anywhere as massive.〔''(Engineering to 1990 )'' - IPENZ, Engineering Publications Co Ltd, Page 6〕 It resembles closely similar bridges of the period, specifically the Howard Taft Memorial Bridge in Washington DC Taft Bridge which took ten years to construct 1897-1907 (as opposed to the two years for Grafton Bridge). In order to dispel doubts about the strength of the still relatively untested type of construction, at the opening in April 1910 two steam rollers were driven across it. This lack of trust also led to a stipulation in the original construction contract that no progress payments should be made, causing the construction company to go into bankruptcy, with the bridge having to be completed by the city. This also added to the final costs, which were around £33,000〔〔(Grafton Bridge ) (from the IPENZ Engineering Heritage Website. Accessed 2008-10-08.)〕 The bridge crosses part of the Symonds Street Cemetery, a historic Auckland cemetery containing the graves of many important early settlers, including the first Governor William Hobson. When the current bridge was constructed the cemetery had been in existence for 70 years and the bridge was inserted in such a way as to require the moving of only eight graves. 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「Grafton Bridge」の詳細全文を読む スポンサード リンク
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