News/Events |
Stainless Steel
Reinforcing Bars (Rebar) Mr. Kevin Cornell (Manager, Salit Specialty Rebar, Niagara Falls, New York) reports that his company has supplied stainless rebar for the restoration of two historic U.S. bridges: The Hadley Bow Bridge (Hadley, New York) and the Wisconsin Avenue Bridge (Washington, D.C.). The Hadley Bow Bridge is a parabolic structure with a span length of 177 ft. It was originally constructed across the Sacandaga River in 1885 and placed on the National Register of Historic Places in 1977. Due to deterioration, the bridge was closed to traffic in 1983. Following extensive repair work, the bridge was re-opened in 2006. Nearly 13 tons of stainless steel rebar (duplex alloy 2205) was used in the reconstruction of the deck and the curbs. The majority of the rebar was #5 (16mm) with some #4 (13mm) used in the curbs.
The Wisconsin Avenue Bridge is an historic stone bridge, spanning the C&O canal in the Georgetown section of Washington. In order to strengthen the bridge, 26 stainless steel rebars were inserted into drilled holes in the stone arch and then grouted in place. The #8 rebars were made of Type 316LN stainless and 24-25ft. long. The total weight of stainless rebar used was 1718 lbs. Further information can be obtained by linking to: http://www.tfhrc.gov/pubrds/05mar/07.htm The independent certification body, UK CARES (based in the United Kingdom), has published a guide to stainless reinforcing steels (Part 7 of The CARES Guide to Reinforcing Steels) - link to this document at http://www.ukcares.co.uk/Guides/PART7.pdf Three significant stainless rebar projects in Asia ...
Total Asian demand projected at around 7000 tons in next 2-3 years. Reference: R. Trate: "Choosing Stainless Steel Rebar", Wire Forming Technology International, Winter 2004, pp.18-19. New Publication on Stainless Steel Rebar from France ... Collection Technique CIMBETON T.81 (Booklet). "Beton Arme D'Inox. Le Choix de la duree". A collaboration between CIMBETON (Centre d'information sur le ciment et ses applications) and I.D. Inox (Institut de developpement de l'inox). April 2004. 110 pages. Links: www.idinox.com and www.infociments.fr BSSA Special Report A report "The use of stainless steel reinforcement in bridges" has been published by the British Stainless Steel Association (BSSA). It is available from the BSSA web site www.bssa.org.uk (look under BSSA Services and Publications). A closely related, full report (by Graham Gedge of Ove Arup and Partners) has also been published previously by this organization in the form of a CD ROM, together with an interactive cost analysis tool. Road Congestion Costs in Chicago The Economist (February 5, 2005 edition) has reported an estimated cost of $4 billion per year to businesses and commuters in Chicago due to road congestion, and with greater projected future demands on the city's aging infrastructure. Road, Sidewalk and Bridge Repairs in Toronto (Canada) $110 million is to be spent by this city on the repair of roads, sidewalks and bridges in 2005 ... with a backlog of $235 million deferred due to budget constraints. Source: K. McGran's article "On the road to ruin?", Toronto Star, February 5, 2005, pB4-B5. The following ASTM standard has been updated and published in the form of a 2004 revision: ASTM A995/A995M Standard Specification for Deformed and Plain Stainless Steel Bars for Concrete Reinforcement. More details can be found by visiting the ASTM web site at www.astm.org. The independent certification body, UK CARES (based in the United Kingdom), has initiated the certification of stainless steel rebar products, noting a significant increase in interest in stainless reinforcement. More information is available at: www.ukcares.co.uk A comprehensive study "Corrosion Costs and Preventive Strategies in the United States", conducted from 1999-2001 by CC Technologies Laboratories with support from FHWA and NACE, has again highlighted the enormous costs of corrosion damage to highway bridges and other infrastructure. Link to www.corrosioncost.com for further details. An ASTM standard on stainless steel wire for concrete reinforcement has been issued. The full title is: ASTM A1022 - 01: Standard Specification for Deformed and Plain Stainless Steel Wire and Welded Wire for Concrete Reinforcement. Stainless steel wire and welded wire reinforcement produced from hot-rolled stainless steel rod is covered by this standard. Further details can be obtained by visiting the ASTM web site at www.astm.org. A brochure, entitled "Stainless Steel Rebar Guidelines for Shipping, Handling, Fabrication and Placement" is available from NiDI and the Specialty Steel Industry of North America (SSINA). It provides many practical tips on how to ensure the necessary level of care required to maintain the many advantages that stainless steel rebar has to offer. These include: what materials to use for tie-downs, lifting devices and to separate the stainless steel from carbon steel; what to look for during visual inspections; how to clean the rebar; and what hand tools to avoid. The brochure is illustrated with colour photos and a list of references is provided. It can be downloaded free of charge from the SSINA web site at the following link: http://www.ssina.com/publications/index.htm It is also available free of charge from the nearest NiDI office. British Standard BS 6744:2001 "Stainless steel bars for the reinforcement and use in concrete - Requirements and test methods" came into effect on 15 September 2001. This standard supersedes BS 6744:1986, which is now withdrawn. The revision contains new grades and strength levels not in the 1986 standard. Informative annexes have been used to give guidance on grade selection, magnetic properties, coefficients of thermal expansion and third party certification. The maintenance burden of aging bridges is becoming heavy. In fact, corrosion of bridges was recognized as being amongst the biggest contributors to the overall cost of corrosion in the U.S. infrastructure. Based on data from the National Bridge Inventory and publications, the total cost to remediate corrosion-induced structural deficiencies was estimated at approximately $30 billion (1999 dollars). (Reference: Materials Performance, March 2000) |
