期刊名称：International Journal of Innovative Research in Science, Engineering and Technology
印刷版ISSN：2347-6710
电子版ISSN：2319-8753
出版年度：2015
卷号：4
期号：10
页码：9813
DOI：10.15680/IJIRSET.2015.0410070
出版社：S&S Publications
摘要：Concrete is very strong in compression but comparatively weak in tension. Steel is very strong intension and provides tensile strength to concrete. The thermal expansion for both steel and concrete are approximatelythe same. This along with excellent bendability property makes steel the best material for reinforcement in concretestructures.Since the invention of R.C.C in 1867, Mild steel was being used as reinforcing material. Plain mild steel (M.S) rebar ofgrade Fe-250 were used till 1960. Later on the high strength cold twisted deformed (CTD) bars were produced by coldworking process.The yield stress of CTD bars are 415 MPa against 250 MPa of M.S rebars. Though the chemical compositions of M.S& CTD bars are same but the physical strength of CTD bars are 60% higher than the M.S steel bars.TMT (Thermo mechanically treated) bars were introduced in India during 1980-1985. TMT bars are having anoptimum combination of high strength, ductility, bendability and other desirable properties.Now a days most of steel companies in India like SAIL, TISCO and RINL are producing Fe-500 or 550garde of TMTbars and not Fe-415 grade of steel bars. If a bridge requires consumption of 1000 tons of M.S. reinforcement for itsconstruction and it is constructed with TMT bars in place of M.S bars, the net consumption will be only 400 tons.
