Abstract
Recently, many High Strength Steel Bars is used in reinforced concrete structure. But, there are no studies solved this question "How high strength steel bars can be utilized effectively in R. C. members?". Solving this question is very important to development of high strength steel bars. This study gives an anser to this question. First, this study proves that the steel strength could be utilized effectively in R. C. members, have an upper limitation, and that this upper limitatinn is restricted by the following voluable conditions. Secondary, in this study, this upper limitation restricted by the following conditions is analyzed by theoletical caluculation. (1) Ultimate bending strength of Beam and Colum. (2) Bending ductility of beam and colum. (3) Shear strength of beam and colum. (4) Shear failure of beams and colums connection. (5) Reduction of Bending Strength by the bars settled through the beams and colum connection. (6) Anchor failure of bend bars. (7) Allowable crack width. (8) Allowable deflection of beam. (9) Allowable deflection of colum at earthquake.
