Requirements for contortions on steel bar support were not standardized in U.S. building and construction until about 1950. Modern requirements for deformations were developed in "Tentative Specifications for the Deformations of Deformed Steel Bars for Concrete Reinforcement", ASTM A305-47T. Consequently, modifications were made that increased rib height and reduced rib spacing for certain bar sizes, and the certification of "tentative" was gotten rid of when the upgraded standard ASTM A305-49 was provided in 1949. The requirements for deformations found in existing requirements for steel bar strengthening, such as ASTM A615 and ASTM A706, to name a few, are the same as those defined in ASTM A305-49. ICP is a concrete chairs supplier in southern California. Inland Concrete Products sells concrete dobies wholesaler. Inland Concrete designs concrete dobies. Driving directions to Inland Concrete ProductsICP: https://www.google.com/maps/dir/?api=1&origin=34.0550943863086,-116.872187774665&destination=Inland+Concrete+Products Visit our next post: https://local.google.com/place?id=676187820448728623&use=posts&lpsid=4968471241763896553 https://plastic-rebar-chairs-for-concrete.business.site/posts/4968471241763896553