Frequently Asked Questions (FAQ) About Stainless Steel Reinforcing Bars

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1 Technical Note Engineering Technical Note ETN-M-2-12 Frequently Asked Questions (FAQ) About Stainless Steel Reinforcing Bars Introduction CRSI routinely receives inquiries concerning various aspects of reinforcing bars, and reinforced concrete design and construction. This Technical Note presents a collection of typical questions that are asked regarding stainless steel reinforcing bars. Most of these questions come from licensed design professionals (LDPs), namely engineers and architects, field personnel (inspectors, code enforcement personnel, and contractors), and state DOTs. Stainless steel reinforcing bars are experiencing increased use in reinforced concrete projects because of the material s inherent properties, which depending upon the chemistry specified, may include corrosion resistance, low magnetic permeability, ductility, or a combination thereof. Figure 1 shows one example of the increased use of stainless steel reinforcing bars on a bridge deck in Minnesota. But what classes a steel as a stainless steel, as opposed to a modified carbon steel? Stainless steel is defined by ASTM A941 (2010b) as steel conforming to a specification that requires, by mass percent, a minimum chromium (Cr) content of 10.5 percent or more, and a maximum carbon (C) content of less than 1.20 percent. As presented herein, there are several stainless steel alloys used for reinforcing bars. The specific alloy used depends on the project requirements and design properties required by the LDP. ASTM A276 Standard Specification for Stainless Steel Bars and Shapes CAN/CSA G30.18 Carbon Steel Bars for Concrete Reinforcement BS 6744 Stainless Steel Bars for the Reinforcement of and Use in Concrete Requirements and test methods DIN Reinforcing steels - Part 1: Grades, properties, marking DIN Reinforcing steels Part 2: Reinforcing steel bars The last set of standards is provided for information should a North American LDP work in parts of the world where ASTM standards are not adopted. The two most commonly used standards internationally are ASTM A955 / A955M and BS What alloys of stainless steel do the ASTM standards permit as reinforcing bars? ASTM A955 / A955M states that the chemical composition of the stainless steel alloy shall be selected for suitability of the application involved by agreement between the manufacturer and the purchaser. This is an important consideration in achieving the desired corrosion resistance or controlled magnetic permeability or both, because these properties are not provided by all stainless steels. Specific frequently asked questions (FAQ) and responses are provided below. Basic Material Characteristics What Standards govern stainless steel reinforcing bars? Stainless steel reinforcing bars should be specified according to ASTM A955 / A955M, Standard Specification for Deformed and Plain Stainless-Steel Bars for Concrete Reinforcement. Other standards for stainless steel reinforcing bars include the following: The chemical composition of the alloy must conform to the requirements of Table 1 in ASTM A276, Standard Specification for Stainless Steel Bars and Shapes. Each alloy is identified by the six-character Unified Numbering System (UNS) designation starting with the letter S followed by five numeric digits. Specifications should always include the UNS number because it indicates the specific chemistry requirement(s). In addition, when recognized by ASTM A276, the common generic name or AISI type designation for

2 to requirements of ASTM A955 / A955M reinforcing steel. All austenitic stainless steels contain chromium and nickel. Manganese is sometimes substituted for some of the nickel to reduce alloy cost. They are identified as S20000 series or S30000 series. Duplex stainless steels are dual-phase alloys with an approximate austenite and ferrite combination. Table 1 provides the UNS numbers, the common or AISI Type names included in ASTM A276, and the primary alloying additions for the most commonly used austenitic and duplex stainless steel reinforcing bars. Stainless steels are low carbon iron based alloys. Their corrosion resistance is determined by their chromium, molybdenum and/or nitrogen content. Nitrogen also increases strength. All stainless steel families include alloys with different levels of corrosion resistance. Photo courtesy of the Minnesota Department of Transportation. Figure 1 Stainless steel reinforcing bar used in the deck of a bridge structure located in Minnesota. the stainless steel alloy is noted in the second column. ASTM A955 / A955M provides guidance regarding the most commonly used alloys for concrete reinforcement, but this is not a complete list of the products that could meet the requirements of the standard. Stainless steels are classified by their microstructure into families: austenitic, ferritic, martensitic, or duplex. Only austenitic or duplex stainless steels are produced Austenitic stainless steels (UNS S24000, S24100, S30400, S30453, S31603, S31653) have traditionally been used as reinforcing bars because they provide an excellent combination of corrosion resistance in concrete, strength, and ductility. Austenitic stainless steels are essentially non-magnetic as well, unless altered by cold working. Duplex stainless steels (UNS S31803, S32101, S32205, S32304) are magnetic and provide higher strength than austenitic stainless steels. There are two duplexes identified by the common name 2205 (UNS S31803 and S32205). Because the composition for UNS S32205 falls within the range of UNS S31803, it can be Table 1 Typical stainless steel reinforcing bar alloys and their primary alloying elements, as recognized by ASTM (1) UNS Designation Austenitic Type or Common Name Manganese (Mn) Chromium (Cr) Nickel (Ni) Composition % Molybdenum (Mo) Nitrogen (N) S24000 XM S24100 XM S30400 (2) S LN S31603 (2) 316L S LN Duplex (Austenitic - Ferritic) Other Elements S S32101 (3) Cu: S S Cu: Notes: (1) ASTM A276 determines chemistry requirements. All alloys are iron-based and have additional residual element maximums. (2) Typically specified for plain rather than deformed reinforcement. (3) UNS S32101 is a patented alloy with more than one licensed producer. 2 Frequently Asked Questions About Stainless Steel Reinforcing Bars [ETN-M-2-12]

3 recertified as UNS S31803, but UNS S31803 cannot be recertified as UNS S These are the most corrosion resistant stainless steel reinforcement alloys on the market. UNS S31803 is most commonly used and readily available. What alloys of stainless steel are presently available as reinforcing bars? All of the austenitic and duplex stainless steel alloys in Table 1 are available as reinforcing bars in the United States. Specifiers should list all of the acceptable alloy options in project specifications. The austenitic alloys 304 (UNS S30400) and 316L (S31603) are typically used for plain rather than deformed reinforcement. The lead times can be significant and minimum order quantities for individual alloys can vary with current demand and stock availability. What is meant by the term lean duplex and how is it applicable to reinforcing bar? Nickel and molybdenum can be expensive elements, and manufacturers have developed stainless steels with less quantity of these elements to produce more price stable and economical products. As addressed previously, the 2205 Duplex (UNS S31803) alloy is fairly common. However, its corrosion resistive properties may be greater than what is needed for reinforcing bars embedded in concrete. As such, lean duplex stainless steels are being developed and contain different combinations of alloying elements than those contained in The 2304 Duplex alloy (UNS S32304) is one example, where the chromium content is slightly higher (23 percent), but the nickel content is reduced (4 percent). Duplex 2101 (UNS S32101) is another example that was recently introduced into North America. What is stainless steel clad reinforcement? Stainless steel clad reinforcement consists of a thin layer of stainless steel over a carbon steel substrate, such as traditional ASTM A615 / A615M or A706 / A706M carbon steel reinforcing bar. The premise of a stainless steel clad bar is that it offers greater corrosion resistance than a conventional carbon steel bar and it is more economical than a solid stainless steel bar. The cladding is metallic, and it is intended to be more resistant to construction site damage than a non-metallic cladding. Special end treatments are required on exposed bar ends to maintain the corrosion resistance. As of the publication date of this technical note, there are currently no producers of stainless steel clad reinforcement in North America and the product has very limited availability. What are the available sizes of stainless steel reinforcing bars? Stainless steel reinforcing bars are available in all of the U.S. conventional bar sizes and the metric sizes used in Canada. U.S. bar sizes are #3 through #11, #14, and #18. Metric sizes in Canada are 10M, 15M, 20M, 25M, 30M, 35M, 45M, and 55M. What are the yield and tensile strengths of stainless steel reinforcing bars? Stainless steel reinforcing bars are available in Grade 60 (420) and Grade 75 (520). The minimum yield (f y ) and tensile (f ut ) strengths are 60 ksi (420 MPa) and 90 ksi (620 MPa) for Grade 60 (420), and 75 ksi (520 MPa) and 100 ksi (690 MPa) for Grade 75 (520), respectively. How are stainless steel reinforcing bars marked? Are they the same as the carbon steel reinforcing bar designations? Markings on stainless steel reinforcing bars indicate point of origin, size designation (Arabic number corresponding to bar designation number), type of steel (the letters SS or CR indicate production to ASTM A955 / A955M) and minimum yield strength (one dot for Grade 60 (420) and two dots for Grade 75 (520)). The categories are the same as for carbon steel bar designations, but the use of two letters for type of steel and the use of dots rather than lines for minimum yield strength are different. The type of stainless steel is provided on the mill certification, as well as on bar tags. In the field, they may be identified using a portable X-ray fluorescence (XRF) apparatus. Do stainless steel reinforcing bars have the same deformation patterns as conventional black carbon steel bars? Generally yes. The deformation requirements defined in ASTM A955 / A955M provide for a two-sided deformation pattern similar to that defined in ASTM A615 / A615M. ASTM A955 / A955M also has requirements for a three-sided deformation pattern, which is unique to stainless steel reinforcing bars. Specific deformation patterns, however, are selected by each mill. Design codes treat the development lengths and lap lengths for stainless steel the same as for carbon steel reinforcing bars. Figure 2 illustrates the three-sided deformation pattern from ASTM A955 / A955M. Illustration copyright ASTM International, Specification A955/A955M-11. Figure 2 Typical three-sided deformed bar. Do stainless steel reinforcing bars have the same weight per foot as conventional black carbon reinforcing steel bars? There is a slight difference in the specific gravity and, therefore, in the weight per foot between stainless steel reinforcing bars and carbon steel reinforcing bars. Duplex stainless steel weight per foot is slightly lower than carbon steel, while the weight per foot CRSI Technical Note 3

4 for austenitic stainless steels is slightly higher. In larger sized bars, the difference in weight per foot will be more pronounced. Table 2 contains the weight per foot for A615 / A615M, and A955 / A955M duplex and austenitic stainless steel reinforcing steel bars by size according to the respective ASTM specifications. Table 2 - Nominal weight per foot of reinforcing bars per ASTM Bar Size A Series; Duplex Alloys 300 Series; Austenitic Alloys Nominal Weight per Foot (lb/ft) # # # # # # # # # # # What are the thermal properties of stainless steel reinforcing bars? Stainless steel reinforcing bars generally have a coefficient of thermal expansion slightly higher than that of carbon steel reinforcing bars. The coefficient of thermal expansion is in the range of 7 to 10 x 10-6 in./in./ F (17 to 19 x 10-6 in./in./ C), depending on the alloy. What does a typical stress-strain curve look like? Stainless steel alloys exhibit a roundhouse curve when stress versus strain is plotted. This means the yield point of the stress-strain curve is less well-defined than with stress-strain curves for conventional steels, where a well-defined yield plateau is exhibited. This effect is less pronounced than in high-strength, carbon steels however. Figure 3 illustrates a representative stress-strain curve for a Grade 75 (520) stainless steel produced according to ASTM A955 / A955M. The curve exhibits a roundhouse shape. ASTM A955 / A955M requires the yield strength to be determined in two ways. Under the first method, the stress value corresponding to a tensile strain of in./in. is to be determined. This is also called the Extension Under Load (EUL) method. The second method, known as the 0.2% offset method, defines the yield strength as the intersection point of the stress-strain curve with a line set at a 0.2% offset strain and drawn parallel to the initial (elastic) portion of the curve. Both values must meet or exceed the minimum yield strength requirement. Both yield strength determination methods are illustrated in Figure 3 with dashed lines. In this example, the yield stress corresponding to EUL is approximately 75,000 psi (520 MPa) and the 0.2% offset method is about 94,000 psi (648 MPa). The stainless steel represented in Figure 3 thus meets the minimum strength requirements for Grade 75 (520) material. How is the stainless steel reinforcing bar available? Bar sizes #3, 10M, #4, #5, and #6 are typically produced into coils and shipped to the fabricator. Coils are economical because of process efficiencies. Coiled bar can reduce waste, as the fabricated bars are made to precise lengths. Bars #7 and larger are typically available in 40 ft. (12 m) straight lengths, due to limitations in pickling bath or cooling bed lengths. This is in contrast to conventional carbon steel reinforcing bars, which are typically available in 60 ft. (18 m) lengths. Engineering Design Issues Into what fabricated shapes can stainless steel reinforcing bars be bent? Stainless steel reinforcing bars can be fabricated into the entire array of standard bend shapes found in the CRSI Manual of Standard Practice (2009) and ACI 315 (1999). The bars are bent to the same diameters as conventional carbon steel reinforcing bars. Are there any special design guidelines for stainless steel reinforcing bars in ACI 318 or AASHTO? Presently, ACI 318 (2011) and AASHTO (2012) generally treat stainless steel reinforcing bars the same as carbon steel reinforcing bars in terms of structural design. The appropriate yield strength will have to be used in the design computations. For earthquake-resistant designs, ACI 318 references tests and analytical studies are required for use and AASHTO limits the use of stainless steel to seismic design category (SDC) A or in members where plastic hinging is not expected. Is it better to lap splice or mechanically couple stainless steel reinforcing bars? It depends on many factors and this will likely become an economic decision. For the smaller bar sizes, the extra length of stainless steel bar to facilitate the splice requirements will likely be cheaper than the selected coupler. For the larger bar sizes, the coupler becomes more economical than the extra length of bar used to make the splice. A mechanical coupler may, however, be a better alternative given job specific constructability conditions, 4 Frequently Asked Questions About Stainless Steel Reinforcing Bars [ETN-M-2-12]

5 Figure 3 - Representative tensile stress versus strain curve for a stainless steel reinforcing bar illustrating a roundhouse behavior. Both the 0.2% offset and EUL methods for determining the yield stress are shown. congestion issues, and/or spacing requirements. ACI 318 Building Code or AASHTO Bridge Design provisions may also influence this decision. What types of stainless steel mechanical couplers are available? Mechanical couplers are commercially available in stainless steel in standard size threaded couplers. Other types (e.g., transition sizes, terminators, etc.) are available with adequate lead time and quantity. Manufacturers should be contacted for special orders. As with any coupler, test data should be utilized to determine suitability of available products. With respect to mechanical couplers, should the stainless steel alloy match the alloy of the coupled reinforcing bars? Not necessarily. The coupler manufacturers have come to the conclusion that it is not economical to produce and inventory couplers in all of the various alloys. Stainless steel couplers are generally available in the UNS S31803 duplex, which is compatible with all of the reinforcing bar alloys. Are there any issues to using couplers with stainless steel bars? From a practical standpoint, the screw type couplers requiring a tapered thread cut into the reinforcing bar are not recommended for bars from XM-28 (S24100) or XM-29 (S24000). The manganese addition makes them more difficult to machine. Threads can be cut, however precautions by the fabricator must be taken to ensure the bar threads are cut properly. This aspect can slow production and increase costs. Can stainless steel reinforcing bars be mixed with other reinforcing steel bars? Stainless steel reinforcing bars can be used in structures with other reinforcing steel bars. An insulator, such as dielectric tape, should be used at intersections of the dissimilar materials. The combination of stainless steel reinforcement for outer layers, where chloride infiltration is expected, and other steel reinforcement for inner layers potentially maximizes the structure s performance while minimizing total costs. There has been a significant amount of research on combining stainless and carbon steel concrete reinforcement, for example, in new construction and repairs. It has been determined that galvanic corrosion is not a concern. There is less galvanic interaction between CRSI Technical Note 5

6 stainless steel and the passive (not corroding) carbon steel, than there is between active (corroding) and passive carbon steel. Alternatively, different steels could be used in separate elements of the structure. For example, if carbon steel reinforcing bars are used in the piers, stainless steel reinforcing bars could be used in the pier caps. When is it desirable to use non-magnetic stainless steel alloys? Non-magnetic alloys are necessary in structures where magnetic neutrality is needed, such as hospitals and medical facilities with MRI equipment, deperming piers for maintenance of metal naval vessels, and toll booth stations with open road tolling facilities (e.g., those utilizing E-ZPass or I-Pass ). In these structures, duplex alloys should be avoided. Can the clear cover distance to stainless steel reinforcing bars be reduced? Will this translate into a savings in the concrete material cost? In some reported instances, LDPs were able to reduce the top and bottom cover over stainless steel reinforcement, for a total reduction of 1 to 2 in. (25.4 to 50.8 mm). This equates to a 12.5 to 25 psf (600 to 1200 Pa) reduction in dead load of the concrete deck. Before making a change in deck thickness, local bridge or building code provisions should be reviewed for acceptance of this type of change. Decreasing the thickness of the deck certainly has the potential to result in marginally lower project costs. However, before making such a ubiquitous reduction in deck thickness, the deck needs to be analyzed for structural capacity and serviceability (i.e., deflections and potential cracking) on account of the reduced depth affecting the overall structural depth, d, and the reduced stiffness through the moment of inertia, I. Recall, for the latter condition, a reduced depth will have a significant influence, as the overall slab depth term is cubed when computing the moment of inertia, I, for deflections. Although the deck has the inert stainless steel reinforcing bar and it should not corrode, serviceability issues could cause future corrosion issues with the underlying superstructure or substructure elements of the bridge. Do all stainless steels have the same resistance to corrosion? No, not all stainless steel alloys identified in ASTM A955 / A955M have similar corrosion properties. The stainless steel alloys produced to the requirements of ASTM A955 / A955M provide varying levels of corrosion resistance, as the standard only establishes minimum requirements. The severity of the service environment, expected chloride exposure, and service life should be considered when specifying appropriate alloys. Critical chloride threshold modeling has been used to determine the most cost effective stainless steel alloy options and where it should be used. The same is true for other properties, such as magnetic permeability. Purchasers are encouraged to specify an alloy for applications in which specific properties are desired. Further, these desired properties should be identified prior to specifying which alloy is appropriate for the application in question. Construction Issues How many stainless steel reinforcing bar producers are there in the United States? Does the Buy America act apply? There are three domestic steel mills that can manufacture stainless steel reinforcing bar to Buy America requirements. The Buy America act applies to government projects such as Federally-funded bridge projects, GSA buildings, Corps of Engineers projects, etc. Additional government requirements exist for the use of patented/proprietary products. Do I need to use stainless steel accessories (e.g., supports, ties, etc.) if I am using stainless steel reinforcing bar? Yes, stainless steel chairs and tie wire are preferred when using stainless steel reinforcing bars. Both are available. Plastic chairs can also be used. Are there any special handling requirements? The Specialty Steel Industry of North America (SSINA) has a publication entitled Stainless Steel Rebar Guidelines for Shipping, Handling, Fabrication, and Placement (2012), which provides additional information on stainless steel reinforcing bar. This publication is available for download at the SSINA website referenced herein. Stainless steel should be kept separate from other ferrous metals (i.e. carbon steel) from the point of pickling to placement of the concrete, to prevent cross contamination. Pickling occurs after the bar is manufactured, where the bars are immersed in a strong acid to remove mill scale. Synthetic web slings should be used to lift bundles, as opposed to regular chains. Bundling wire should be plastic coated or stainless steel. Fabrication of stainless steel reinforcing bars uses the same process as for carbon reinforcing steel bars. However, the contact surfaces of equipment used to fabricate or handle stainless steel bars should not have been previously used for carbon steel, low alloy steel, low carbon chromium steel, or other non-stainless ferritic materials. Ideally, fabrication equipment should be dedicated to the fabrication of stainless steel reinforcing bars, unless adequate cleaning or contamination isolation procedures are in use. What is the availability of stainless steel reinforcing bar? What are the lead times necessary to order and get the bar fabricated? Stainless steel reinforcing bar is available through several domestic and foreign steel mills, and domestic fabricators given sufficient lead times in the ordering process. Purchasers are encouraged to inquire with a local fabricator about lead times for specific grades, sizes, and quantities early in the project schedule. 6 Frequently Asked Questions About Stainless Steel Reinforcing Bars [ETN-M-2-12]

7 What is the cost of stainless steel reinforcing bar compared with conventional black bar or other corrosion resistant bars on the market? Why does stainless steel typically have a surcharge on the material cost? As a trade organization, CRSI does not comment on costs. Specific manufacturers or suppliers should be contacted for current pricing information. We can, however, explain the purpose of the surcharge. The cost of stainless steel alloying elements, such as iron, chromium, nickel, and molybdenum, fluctuate in the world commodity markets (for example, on the London Metal Exchange, referenced at com/). Like all metals, price is controlled by commodity prices for alloying elements, scrap, and energy costs. The current price of any stainless steel alloy is the base price plus the surcharge, which is adjusted monthly to reflect alloying element cost variations. Alloys that contain less of the more expensive alloying elements have greater price stability. For a large project, a reinforcing bar fabricator is taking a risk when purchasing the bar from a mill due to these dramatically fluctuating prices versus the bid price provided to the general contractor. Ideally, when the bar is delivered, the reinforcing bar is fabricated and delivered to the jobsite as soon as possible, so payment can be made. If the fabricator purchases the material in advance, and the project gets delayed with a commensurate decline in market price, the fabricator will likely have some very expensive inventory. For this reason, the fabricator may ask for a proportion of the payment up front to purchase the material. Moreover, if the fabricator purchases the material and the project gets delayed, the fabricator will likely ask for material storage costs to relieve some of the burden of making the advanced purchase. Are there any storage issues on the project site that could impact the use of stainless steel reinforcing bar? Stainless steel should be stored separately from carbon steel to prevent contamination from mill scale and other ferrous materials. Stored bars should be elevated off the ground on timber dunnage. In consideration of the high market value for stainless steel scrap, provisions should be made to minimize the chances of loss or theft of the product at the jobsite. This may include, at a minimum, locked storage, enhanced inventory control measures, video surveillance and/or a manned security presence. Finish Quality Some State DOT specifications have a requirement for finish quality. Is this necessary? ASTM A955 / A955M requires stainless steel reinforcing bar to be pickled unless specified by the purchaser. Sometimes in the production and fabrication of stainless steel products, the metal can become contaminated and this may affect its corrosive resistive properties on the surface. Usually contamination is localized to the point of contact. Superficial surface corrosion staining from embedded carbon steel particles can be removed in accordance with ASTM A380 Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and Systems (2006). This removes surface contamination and restores the stainless steel to its normal passive film surface layer. I recently had a bridge deck project where the stainless steel bar was exposed to the elements for a long time because of a construction delay. Some of the bars discolored with a brown hue that appeared to be rust staining. Is this a concern? If discoloration occurs, it is likely superficial and usually the result of the material, the material processing (i.e., pickling), or contamination with carbon steel particles. Care should be taken when handling, fabricating, and storing stainless steel to avoid exposure to carbon steel. Contamination may result in discoloration due to rusting of the carbon steel particles on the stainless steel. Improper pickling, or other treatment, can also result in exposure to contaminants and cause discoloration. The cause of the discoloration should be determined in order to assess its significance. Pickling paste is available for touch-up in the field, and should be used in accordance with ASTM A380. References American Association of State Highway and Transportation Officials AASHTO (2012), AASHTO LRFD Bridge Design Specifications, U.S. Customary Units, 6th Edition, American Association of State Highway Officials, Washington, D.C., 1672 pp. American Concrete Institute ACI Committee 315 (1999), Details and Detailing of Concrete Reinforcing, American Concrete Institute, Farmington Hills, Michigan, 44 pp. American Concrete Institute ACI Committee 318 (2011), Building Code Requirements for Structural Concrete (ACI ) and Commentary (ACI 318R-11), American Concrete Institute, Farmington Hills, Michigan, 503 pp. ASTM International ASTM A276 (2010a), Standard Specifications for Stainless Steel Bars and Shapes, ASTM A276-10, ASTM International, West Conshohocken, PA, 7 pp. ASTM International ASTM A380 (2006), Standard Practice for Cleaning, Descaling, and Passivation of Stainless Steel Parts, Equipment, and Systems, ASTM A380-06, ASTM International, West Conshohocken, PA, 13 pp. ASTM International ASTM A615 (2012a), Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement, ASTM A615 / A615M 12, ASTM International, West Conshohocken, PA, 6 pp. CRSI Technical Note 7

8 ASTM International ASTM A706 (2009), Standard Specification for Low-Alloy Steel Deformed and Plain Bars for Concrete Reinforcement, ASTM A706 / A706M 09b, ASTM International, West Conshohocken, PA, 6 pp. ASTM International ASTM A941 (2010b), Standard Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys, ASTM A941 10a, ASTM International, West Conshohocken, PA, 8 pp. ASTM International ASTM A955 (2012b), Standard Specification for Deformed and Plain Stainless- Steel Bars for Concrete Reinforcement, ASTM A955/ A955M 12, ASTM International, West Conshohocken, PA, 13 pp. British Standards Institute BSI 6744 (2009), Stainless Steel Bars for the Reinforcement of and Use in Concrete, Requirements and Test Methods, BS 6744, British Standards Institute, London, United Kingdom, 28 pp. Canadian Standards Association CSA G30.18 (2009), Carbon Steel Bars for Concrete Reinforcement, CAN/CSA G , Canadian Standards Association, Mississauga, Ontario, 28 pp. Deutsches Institut für Normung e. V. DIN (2009a), Reinforcing steels - Part 1: Grades, properties, marking, DIN 488-1, Deutsches Institut für Normung e. V. (German Institute for Standardization), Berlin, Germany, 17 pp. Deutsches Institut für Normung e. V. DIN (2009b), Reinforcing steels Part 2: Reinforcing steel bars, DIN 488-2, Deutsches Institut für Normung e. V. German Institute for Standardization), Berlin, Germany, 11 pp. Specialty Steel Industry of North America SSINA (2012), Steel Rebar Guidelines for Shipping, Handling, Fabrication, and Placement, Specialty Steel Industry of North America, Washington, D.C., 6 pp. Note: References listed above were used in the development of this document. Because these documents are updated on a frequent basis, the year has generally been omitted in the text for clarity. The licensed design professional is referred to the respective organization for the latest revisions and applicable year of adoption. Concrete Reinforcing Steel Institute CRSI (2009), Manual of Standard Practice, 28 th Edition, Schaumburg, Illinois, 144 pp. Disclaimer CRSI does not endorse any patented technology or warrant that the use of this patented technology will meet code requirements. The use of any patented technology is at the option of the user. Contributors: The principal authors on this publication are Danielle D. Kleinhans, PhD, PE, and Neal S. Anderson, PE, SE, with review by members of the CRSI Durability Committee. Keywords: Stainless steel, reinforcing bar, deformations, couplers, corrosion, alloys, handling, storage, magnetic Reference: Concrete Reinforcing Steel Institute - CRSI [2012], Frequently Asked Questions (FAQ) about Stainless Steel Reinforcing Bars, CRSI Technical Note ETN-M-2-12, Schaumburg, Illinois, 8 pp. Historical: None. New technical note Note: This publication is intended for the use of professionals competent to evaluate the significance and limitations of its contents and who will accept responsibility for the application of the material it contains. The Concrete Reinforcing Steel Institute reports the foregoing material as a matter of information and, therefore, disclaims any and all responsibility for application of the stated principles or for the accuracy of the sources other than material developed by the Institute. 933 North Plum Grove Rd. Schaumburg, IL p f Regional Offices Nationwide A Service of the Concrete Reinforcing Steel Institute 2012 This publication, or any part thereof, may not be reproduced without the expressed written consent of CRSI. Printed in the U.S.A.