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Improving Tomorrow’s Infrastructure: Extending the Life of Concrete Structures with Solid Stainless Steel Reinforcing Bar. Stainless Steel World America 2008 Conference September 9 & 10, 2008 Presented by Talley Metals a Carpenter Company. Progresso, Mexico piers. Functioning Pier
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Improving Tomorrow’s Infrastructure: Extending the Life of Concrete Structures with Solid Stainless Steel Reinforcing Bar Stainless Steel World America 2008 Conference September 9 & 10, 2008 Presented by Talley Metals a Carpenter Company
Progresso, Mexico piers • Functioning Pier • Built over 70 years ago (1937) • Used stainless steel - 304L • Still has an additional 30 year life expectancy • Non-functioning pier • Built 30 years ago • Carbon steel rebar The information and data presented herein are typical or average values and are not a guarantee of maximum or minimum values. Applications specifically suggested for material described herein are made solely for the purpose of illustration to enable the reader to make his/her own evaluation and are not intended as warranties, either express or implied, of fitness for these or other purposes.
Stainless Steel • Achieves its corrosion resistant characteristics through the formation of an invisible chromium oxide (Cr2O3) film. • This oxide forms, on the surface of the material and creates a corrosion resistant barrier. • Stainless steel must contain a minimum of 12% chromium in order to be considered a true stainless.
Hot Rolling and Acid-Cleaning • Product is hot worked to size on a rolling mill, prior to the deformation pattern that is added to the surface, then it is shot blasted and acid cleaned, to remove any scale and allow a passive oxide film to form.
Reinforcing Bar Issues/ Concerns • Deteriorating structures due to corrosion • Salt environment in coastal regions • Heavy de-icing areas • Initial cost vs. Life Cycle Costs • Need to base product selection on life cycle costs, not budgetary costs • Concern is growing in seismic regions • Maintenance and repair costs • Public inconvenience, especially in dense traffic and limited access areas
Current Market Demands/Issues • Need for Solid Stainless Steel Rebar for its corrosion resistance and strength • Rising raw material costs for Nickel and Molybdenum • Results in a negative impact on stainless steel rebar prices • Lower priced stainless products are desired by bridge engineers • Must meet ASTM - A955 for strength and corrosion resistance
Stainless Steel Rebar Advantages • Superior corrosion resistance (chlorides) • Superior strength levels and durability • Outstanding ductility at high strength • Long life (100+ years) • Eliminates the need for any coatings • Cost competitive in a full life-cycle projection • Most stainlesses are non-magnetic for MRI applications, deperming piers
Typical Mechanical Properties for Stainless Rebar Alloys EnduraMet is a registered trademark of CRS Holdings, Inc., a subsidiary of Carpenter Technology Corporation
Cost savings opportunities using solid stainless steel • Longer life of structure • Stainless steel rebar has demonstrated a life expectancy of 100+ years. • Reduced concrete cover • Less concrete cover required with stainless rebar, which reduces the deck weight. • Reduced superstructure • Reduced deck weight, results in a reduced weight of the superstructure.
Some construction projects using Talley-produced stainless rebar • Haynes Inlet Slough Bridge in Oregon • Belt Parkway in NY City • Garden State Parkway in NJ • Driscoll Bridge in NJ • Lincoln Tunnel in NY • Woodrow Wilson Bridge (Washington, DC) • Deperming Piers (Norfolk Naval Yard)
Using Stainless Steel Rebar • Used in critical design areas • Such as bridge decks, barrier walls, columns, foundations, and ramps • Minimal maintenance and/or repair costs • Reduce out-of-service disruptions • FHWA slogan • Get in, get out, stay out! • Life expectancy of 100+ Years
Thank you for your interest in solid stainless steel reinforcing bar. More information about Carpenter’s products is available on this website including technical datasheets about EnduraMet stainless and the white paper. Go to Technical Articles and select the August 2007 article “Improving Tomorrow’s Infrastructure.” To contact Carpenter, call 1-800-654-6543 in the U.S. or refer to the Contact Us page for the location nearest you.