DUCTILITY OF HIGH-STRENGTH REINFORCED-CONCRETE COLUMNS

Based on the experimental research of 48 reinforced concrete columns u sing high strength and normal strength concrete under monotonic and cy clic loading, the factors which affect the ductility, such as the conc rete strength, axial load ratio, stirrup volume ratio, etc., are analy zed. It can be concluded that the axial load ratio is the most importa nt factor that affects the ductility. The axial load ratio limits and relative stirrup volume ratio limits were proposed under the condition of limited ductility (mu(Delta) greater than or equal to 3). The expe riments also show that the relationship between the stirrup ratio and axial load ratio is not linear if the axial load ratio is high, which is different from the finding of previous research. In the design, a s implified bilinear relationship can be adopted which agrees well with the experimental results.