TPi July 2009

developments products &

The use of steel for modern bridges has grown significantly over the last twenty years, with engineers recognising the benefits and versatility that steel offers as a construction material. Steve Whitfield, technical manager at Corus Tubes, considers how the steel industry is leading the way when it comes to the design and construction of footbridges. Modern steel bridges benefit from the latest improvements in automated fabrication and construction techniques to provide economic solutions to meet the demands of safety, rapid construction, aesthetic appearance and minimal maintenance. One recent project to realise the benefits that structural steel offers is a new £5 million footbridge in North Lanarkshire, Scotland. Delivered on behalf of Transport Scotland, the new bridge spans the M8 motorway, replacing an existing footbridge that was originally built in 1965. Located on one of the busiest stretches of road in The bridge challenge

Scotland, the new footbridge forms an essential element in the upgrading of the transport hub now operating on the site. Bridges are significant structures that have the power to add or detract from the landscape. Specifying steel at the conceptual stage of the design is one way in which designers can ensure that their architectural aspirations are realised. It is an incredibly strong material that can be easily shaped, which gives the advantage of being able to significantly improve the aesthetic appearance of the structure, as all of the main structural members can form smooth curves throughout its entire length.

The new bridge features a helical truss design

An initial study was undertaken to look at different options for the proposed structure at Harthill. Having considered and evaluated several different design options for the new 90-metre bridge, the recommended solution incorporated a helical truss design, similar to that used on the Greenside Place link bridge in Edinburgh. Presenting many benefits when it comes to bridge design, a helical truss is composed of steel members connected at their ends by hinged pin connections to form a stable configuration. The open framework results in elements being primarily in tension or compression, creating a very light but stiff form of construction. In addition, a helical truss is perfect for footbridge construction as it minimises the effective construction depth and the length of approach embankments. Custom-designed and factory-manu- factured, the bridge offers a high quality solution that can easily be delivered to site for instant installation, and, in the instance of the M8 footbridge, an aesthetically impressive final structure.

2,000 types of welded and seamless steel tubes

Shenyang Dongyang Special Section Tube Co, Ltd is a joint venture company founded in 1991. The company is mainly engaged in producing more than 2,000 kinds of welded and seamless structure steel tubes with compound sections, such as square, rectangle, ellipse, semicircle, arch, sector, triangle, hexagon and octagon.

Materials used include carbon steel and stainless steel, and other alloyed material. The company passed quality system certification of ISO9001:2000 in 2002. The company’s products can be produced according to national and international standards including Chinese GB, JIS, DIN, EN and ASTM. The products are widely used in the

Products from Shenyang Dongyang S S Special Section Tube Co

manufacture of vehicles, bridges, municipal engineering construction, and in the chemical, petroleum, food, energy, electricity, aviation and aerospace industries. Products include hot-finished and high strength steel tube according to EN10210 and EN10219. The highest yield strength can reach 690MPa (100 KSI). The company also possesses equipment for curving, straightening, cutting and polishing, for further processing of the steel tubes.

Shenyang Dongyang Special Section Tube Co, Ltd – China export@tts.com.cn • www.tts.com.cn

The impressive structure at Harthill took full advantage of the aesthetic properties

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Tube Products International July 2009

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