Robust Analysis of Current Reliability-Based Design Method for RC Columns with Tension Failure under Random Eccentricity.

Abstract

The current methods for designing reinforced concrete (RC) columns are mainly based on the reliability calibration under fixed eccentricity criterion. However, for an RC column under combined vertical gravity load and horizontal earthquake action, its eccentricity would be random due to probability properties of these loads. According to the capacity models in Chinese code, the failure function with random eccentricity is obtained and found to be a complex one, which is largely different from the one obtained by the fixed eccentricity criterion. Based on the prescribed statistical models of relevant variables, the differences of failure probability are analyzed for RC columns with different load effect ratios and different strong column factors by the Monte Carlo method. Compared with the fixed eccentricity case, such differences under random eccentricity would be much larger among different cases. Thus, the current design method of RC column is hard to achieve a robust design.