WCA January 2017

From the Americas expects demand in China to have fallen only one per cent to 665.6mmt for the year. It sees Chinese demand falling two per cent to 652.3mmt in 2017. Worldsteel, formerly the International Iron & Steel Institute (IISI), said the $900 billion global steel industry remains vulnerable to geopolitical and economic uncertainties. In particular, T V Narendran, chairman of the Worldsteel economics committee, told Reuters in Dubai (11 th October), “Downside risks come from the high corporate debt and real estate market situation in China.” An old but unexploited girdering system offers new advantages for construction of short-span steel bridges A group of steel-bridge advocates has responded to a call from the USA Federal Highway Administration (FHWA) for a cost-effective accelerated bridge construction system for steel bridges 140 feet or less in length. The Short Span Steel Bridge Alliance (SSSBA), in conjunction with West Virginia University (WVA) and Marshall University, a research college, has produced a new type of tub girder that is said to require less fabrication and installation time. As reported by Aileen Cho of the Engineering News-Record (Troy, Michigan), SSSBA organised a modular steel-bridge task group to explore possibilities, from twin-tub girders to orthotropic decks. The group, made up of more than 30 partners from the steel industry, academia, government organisations and bridge owners, developed the pressed-brake tub-girder (PBTG) system in three years. The system is described as consisting of shallow, modular, galvanised trapezoidal boxes fabricated from cold-bent structural steel plates. The concrete deck is precast on the girder and the modular unit shipped by truck to the bridge site. (“Industry Group Introduces a Pressed-Brake Short-Span Steel-Girder System,” 12 th October) SSSBA fabricates its girders from standard steel plates, typically 72 " or 96 " wide, supplied by a mill. Greg Michaelson, an assistant professor at Marshall University (Huntington, West Virginia), said a plate is hit with a press brake four times – twice on the ends and twice in the centre – to achieve the U-shaped tub. With shear studs on the top flange and diaphragms, the concrete deck completes the composite unit. The concept of a pressed-brake tub-girder system was not new but had not been fully developed, said Karl Barth, an engineering professor at WVU. “What we’re doing is taking all the advantages of a large, deep, welded tub girder and scaling [it] down to a short-span bridge system,” he told Ms Cho. “All the bracing, welding, and other details that go into a large tub girder simply couldn’t be economically deployed in short spans.”  According to the SSSBA, cold-bending of the section – instead of cutting and welding – delivers as much as a 50 per cent reduction in fabrication costs, compared to proprietary cold-formed box-girder systems. There are economies, as well, in fewer stiffeners and cross frames, the group said. And the girders can be used for both tangent and skewed configurations.

Dr Barth noted that, while cold-bending steel fabricators often make crane booms and utility poles, they are not necessarily traditional bridge fabricators. Thus, he said, the PBTG system could create a new business line for operators of large press brakes. Elsewhere in steel . . .  Steelmaking is returning to the southeast of England: specifically to the Sheerness plant in Kent which was closed down in 2012 but is to be restarted by the industrial group Liberty House. Having signed a long lease with Peel Ports, owner of the site, Liberty intends to have the rolling mills at Sheerness – with capacity of 750,000 metric tons a year – back in production by the summer. As reported by Alan Tovey of the Telegraph (14 th October), the Sheerness news came almost exactly a year after the company reopened a steel mill in Newport, South Wales; and two weeks after it restarted the Dalzell works – Britain’s largest steel plate mill – near Glasgow, acquired from Tata which had intended to phase out production there. Liberty was understood to be planning to relocate the electric arc furnace from Sheerness to the Newport plant. V B Garg, CEO of Liberty Steel Newport, told the Telegraph that the decision to keep the rolling mills at Sheerness, rather than moving them elsewhere, was dictated by considerations of cost and the prospect of “[allowing] us to take advantage of emerging opportunities in the market.” Telecom New Los Angeles-to-Hong Kong subsea cable will allow users to choose from a variety of interoperable network equipment Chris Preimesberger reported on eweek.com (12 th October) that the “head-butting” USA online advertising rivals Google and Facebook, whose campuses are located only a few miles from each other on San Francisco Bay, are going into the fibre optic cable business together. The two web services giants are working together to lay a cable between Los Angeles and Hong Kong that will serve their users on both sides of the Pacific; and, eventually, perhaps transport data from public and/or private data networks. According to Brian Quigley, Google’s director of networking infrastructure, the new Pacific Light Cable Network (PLCN) will have 7,954 miles of fibre and an estimated cable bandwidth of 120 terabits per second (Tbps). This speed is double that of the current highest-capacity trans-Pacific route FASTER – a Google-backed cable system which connects hubs on the USA West Coast with Japan and elsewhere in Asia. The other members of the FASTER consortium are China Mobile International and China Telecom Global (both Hong Kong-based), Global Transit (Malaysian), KDDI (Japanese), and SingTel, of Singapore.

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Wire & Cable ASIA – January/February 2017

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