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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
Copyright 2008, CRS Holdings, Inc.
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.
Copyright 2008, CRS Holdings, Inc.
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.
Copyright 2008, CRS Holdings, Inc.Chromium, %
0 5 10 15 20 25 300
25
50
75
100
125
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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.
Copyright 2008, CRS Holdings, Inc.
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
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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
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• 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
Stainless Steel Rebar Advantages
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Life Cycle Cost Analysis (by NIDI)
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Grade 40 (280) 60 (420) 75 (520)
Yield Strength 40,000 60,000 75,000(min psi)
Tensile Strength 70,000 90,000 100,000(min psi)
Minimum Elongation 20 20 20(%)
ASTM - A955/A955M – 07afor Stainless Steel Reinforcing bar
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Alloy UNS Yield Strength Tensile Strength % EL % RADesignation (KSI) (KSI)
EnduraMet 2205 S31803 95-110 130 25 65
EnduraMet 316LN S31653 65-80 110 40 70
EnduraMet 32 S24100 85 125 45 50
EnduraMet 33 S24000 85 125 45 50
Typical Mechanical Properties for Stainless Rebar Alloys
EnduraMet is a registered trademark of CRS Holdings, Inc., a subsidiary of Carpenter Technology Corporation
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Alloy UNS % % % % % %Designation Cr Ni C N Mo Mn
EnduraMet 2205 S31803 22 6 <.03 0.17 3 2
EnduraMet 316LN S31653 17 10 <.03 0.12 2.1 2
EnduraMet 33 S24000 17 3.5 0.04 0.3 0.5 14
EnduraMet 32 S24100 17 0.7 0.04 0.3 0.5 14
Typical Chemical Compositions for Stainless Rebar Alloys
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Ease of Forming Stainless Steel Rebar
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Stainless rebar on deck – Haynes Inlet Bridge, Oregon
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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.
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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)
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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
Copyright 2008, CRS Holdings, Inc.
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.