Strength reduction factor evaluation of the circular reinforced concrete column with varying eccentricity ratio (e/h)

Abstract

This paper presents strength reduction factor evaluation of circular reinforced concrete column with varying
eccentricity ratio (e/h) using the first-order-reliability-methods. The resistance properties of the reinforced concrete column is
estimated using the monte-carlo simulation with random normally distributed material properties. Only dead and live load
combination considered in the analysis. The parameters being investigated when evaluating the resistance of the reinforced
concrete column are the concrete compressive strength, steel yield strength, coefficient of variation for both the concrete and
steel materials, reinforced concrete column size, and the longitudinal reinforcement ratio. When evaluating the strengthreduction factor, the safety index values are 3.0, 3.5, and 4.0. From the analysis, it was found out that the strength reduction
factor, for e/h higher than one and with safety index equal to 3.0, was equal to 0.9 which agrees well with the ACI 318 strength
reduction factor for tension-controlled region. However, for e/h lower than one and safety index equal to 3.0, the strength
reduction factor was equal to 0.6 which was lower than the ACI 318 strength reduction factor for compression-compression
controlled region.