Assessment of time-dependent reliability of reinforced concrete columns with uncertain load eccentricity

An approach for the time-dependent reliability analysis of reinforced concr ete (RC) columns considering the correlation between the axial load and the bending moment or the uncertainty in the load eccentricity is presented. T he approach recursively uses the efficient first-order reliability method f or the time-dependent reliability analysis. The proposed approach is more e fficient than the ones used in the literature for the reliability analysis of RC columns. The proposed approach is used to carry out sensitivity analy ses of the reliability of short RC columns to the time-dependent live load effects and to the correlation between the axial load and the bending momen t. Results of the analyses suggest that the reliability of RC columns can b e sensitive to the correlation between the axial load and the bending momen t due to live load. The differences between the reliability indices obtaine d by considering the live load modeled as a pulse process and as an extreme variate can be large.