A probabilistic study on the ductility of reinforced concrete sections

Although the current design codes apply reliability-based calibration procedures to evaluate safety factors for the strength based limit state, the safety factors used to ensure minimum ductility capacities are rather simple and are not resulted from a probability-based procedure. This study examines level of safety delivered by the current design codes with regards to providing minimum curvature ductility for reinforced concrete (RC) beams made with normal strength concrete. Reliability analysis results show that with regard to the strength limit state, the considered design codes are in good agreement with one another. However, there is considerable disparity in the level of safety provided for minimum curvature ductility amongst the codes. The provided reliability for the design to remain ductile is too low in some and just about acceptable in the others. This signifies the importance and the need to introduce reliability based methods of design for ductility.