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415 REINFORCING STEEL-BAR SUPPORTS. (1-15-10) (FA 1-21-10) (7-10) SUBARTICLE 415-5.13(Pages 438-439) is deleted and the following substituted 415-5.13 Bar Supports: 415-5.13.1 General: Provide reinforcing steel bar supports manufactured in accordance with all requirements of the CRSI Manual of Standard Practice. Use bar supports of adequate strength to withstand a 300 pound concentrated load applied as directed by the State Materials Office without permanent deformation or breakage, with the deformation under a 300 pound load being less than 5% of the support height. Ensure that no more than 5% of the reinforcing steel bar supports exhibit unsatisfactory performance, breakage, or permanent deformation during rebar tying and/or concrete placement operations. Ifa bar support does not achieve this level of performance, reduce the average spacing between bar supports by 15%, or remove that product from use on the job. Ensure that bar supports do not move during concrete placing operations. To prevent movement, tie supports to the reinforcing steel. When using bar supports on corrugated metal stay-in-place forms, use supports specifically designed for the form being used. For structural elements located in extremely aggressive environments, do not use metal bar supports in contact with forms or floor surfaces to support reinforcing steel. 415-5.13.2 Metal Bar Supports: For metal bar supports in contact with steel stay-in- place forms and metal bar supports in contact with boundary surfaces of concrete to be cast, provide supports constructed with molded plastic legs or plastic protected steel legs. Do not allow any portion of the bar support other than the molded plastic leg or plastic protected portion of the steel leg to be closer than 1/2 inch from the boundary surface of concrete to be cast. Certify that all metal bar supports meet the following requirements: (I) That they are manufactured from cold drawn stee I wire in accordance with the wire sizes and geometrical dimensions shown in the CRSI Manual of Standard Practice, Chapter 3, Table II. (2) That the plastic used for protection of the steel legs has a thickness of 3/32 inch or greater at points of contact with the form work. Provide plastic protection by a dipping operation, by adding premolded plastic tips to the legs of the support or by molding plastic to the top wire of the support. Ensure that the plastic material used for protection of steel legs does not chip, crack, deform, or peel under ordinary job conditions. Provide molded plastic legs that have sufficient strength to carry the weight of the supported reinforcing steel in its required position without deformation and relaxation under job conditions. 415-5.13.3 Plastic Bar Supports and Spacers: Use non-stackable bar supports and spacers comprised of either reinforced or non-reinforced virgin or recycled plastic. Bar supports shall be able to meet the concentrated load requirements of 415-5.13.1 within a working temperature range of20 to 150oF. Spacers shall be able to withstand a 50 pound concentrated load applied as directed by the State Materials Office without bar slippage, permanent deformation or breakage within a working temperature range of20 to 1500F with the deformation under a 50 pound load being less than 5% of the support height. All plastic rebar supports shall have a maximum water absorption of 0.5% at 14 days, as per ASTM 0 570. Protect plastic rebar supports from exposure to sunlight until placed in the form. Mold plastic rebar supports in a configuration which does not restrict concrete flow and consolidation around and under the rebar support. Do not use continuous legs or rails on concrete surfaces. Due to the wide range of applications and heights, ensure that the manufac turer additionally certifies all plastic bar supports for 2 inch, 3 inch, 4 inch and 4 1/2 inch heights.