Sir Leo Hielscher Bridges

Construction on the Gateway Bridge commenced on 5 June 1980. The construction of the bridge started before the design was completed, to fast track its construction. It was officially opened on 11 January 1986 by Premier of Queensland Joh Bjelke-Petersen. On this day 200,000 people crossed the bridge by foot as part of the opening activities. In 2001 the bridge was crossed by 27 million vehicles (approximately 73,975 vehicles per day). In early 2010 the single bridge was carrying an average of 100,000 vehicles per day. ==Design==

In 1979, a tender was called by the Queensland Main Roads Department for a new bridge crossing of the Brisbane River. The conforming design main span was designed as a balanced cantilever with two raised post tensioned concrete compression stays located on the median and over each of the two main piers to support the 260-metre span. Due to the proximity of the Brisbane Airport, an overall structural height constraint was provided due to aircraft flight path and clearances. This constraint ruled out the possibility of a conventional cable-stayed bridge due to the height of the pylons that would be required. Due to cost considerations, an alternative design concept was proposed by Bruce Ramsay (Manager Engineering) of VSL. This alternative design required a world record main span of 260 m for a free cantilever, concrete box girder bridge. The concept was adopted by one of the tenderers – Transfield Queensland Pty.Ltd. who was subsequently awarded the project on the basis of this alternative. It held the record span of 260 m for over 15 years. The box girder is still the largest prestressed concrete, single box in the world, measuring 15 m deep at the pier, with a box width of 12 m and an overall deck width for the six lanes of 22 m. As stated above the bridge owes its distinctive shape to air traffic requirements restricting its height to under above sea level (all features of the bridge including light poles) coupled with shipping needs requiring a navigational clearance of . The bridge has six lanes (originally three lanes in each direction, which were subsequently reconfigured to six lanes of northbound traffic after opening of the duplicate bridge). The bridge was financed by funds borrowed by the Queensland Government, and as a result, users of the bridge pay a toll when crossing the bridge in either direction. The bridge is operated and maintained by Transurban Queensland. The total length is . This is divided into a southern approach of , a northern approach of and the three central spans of . The record main span is long by high, which is equivalent to a 20-storey building. A total of 150,000 tonnes (165,000 short tons) of concrete was used to construct the bridge. The original design did not include a safety fence to prevent suicide attempts and base jumping. Anti-climbing screens are part of the second bridge's security features. ==Duplication==

(Rivergate Marina) In 2005, a major upgrade of the Gateway Motorway was announced. The duplicate bridge was specified to have a design life of 300 years. To the south, the upgrade included widening of the Gateway Motorway from four to six lanes. To the north, it involved the construction of the Gateway Motorway deviation, an entirely new six-lane motorway between the Gateway Bridge and Nudgee Road. The deviation runs east of the original motorway through Brisbane Airport Corporation land and provides an alternative means of access to Brisbane Airport (the only effective access from the south). The new bridge provides a bicycle path unlike the first crossing. In October 2010, then Minister for Main Roads, Craig Wallace, announced that the original course of the Gateway Motorway via Eagle Farm would be renamed to Southern Cross Way, after Sir Charles Kingsford Smith's aircraft, the Southern Cross, which landed at Eagle Farm in 1928, and so as to avoid confusion with the newly opened Gateway Motorway deviation. The new Gateway Motorway deviation was given the name Gateway Motorway. However, like the renaming of the bridges themselves, the change to Southern Cross Way was not without controversy, attracting criticism from the then Shadow Minister for Main Roads and Transport, Fiona Simpson. Refurbishment of the existing bridge was completed in November 2010. == Awards ==

In 2009 as part of the Q150 celebrations, the Gateway Bridge was announced as one of the Q150 Icons of Queensland for its role as a "structure and engineering feat". ==See also==