High steel reinforcement has been studied extensively in the past few years. It reduces steel congestion in heavily reinforced members, and thus save both labor and material costs. However, influences of different stress-strain characteristics between different steels are not well understood. In addition, the current ACI code (ACI 318 committee, 2011) limits the design strength of reinforcements at 80 ksi. This limitation prevents engineers from fully using enhanced strength properties of these materials. In order to use high strength steel in practical field, concerns regarding the use of high strength steels need to be clarified and design recommendations consistent with the structure of current building code should be provided.
Focus of this research is given to the application of high strength steel as flexural reinforcement in RC beam members. Two types of high strength steels are selected in this study; each with specified yield strength at 100 ksi and marked labeled as SD 685 and ASTM 1035 Grade 100. Through an analytical formulations experimental program where ten full-scale RC beam specimens are subjected to monotonically increased load, the potential of using high strength steel as flexural reinforcement is evaluated. The result should lead to a design recommendation when using high strength steel, including ASTM 1035 and SD 685, for RC material.

High steel reinforcement has been studied extensively in the past few years. It reduces steel congestion in heavily reinforced members, and thus save both labor and material costs. However, influences of different stress-strain characteristics between different steels are not well understood. In addition, the current ACI code (ACI 318 committee, 2011) limits the design strength of reinforcements at 80 ksi. This limitation prevents engineers from fully using enhanced strength properties of these materials. In order to use high strength steel in practical field, concerns regarding the use of high strength steels need to be clarified and design recommendations consistent with the structure of current building code should be provided.
Focus of this research is given to the application of high strength steel as flexural reinforcement in RC beam members. Two types of high strength steels are selected in this study; each with specified yield strength at 100 ksi and marked labeled as SD 685 and ASTM 1035 Grade 100. Through an analytical formulations experimental program where ten full-scale RC beam specimens are subjected to monotonically increased load, the potential of using high strength steel as flexural reinforcement is evaluated. The result should lead to a design recommendation when using high strength steel, including ASTM 1035 and SD 685, for RC material.

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