Reliability Analysis of Beams Strengthening with Augmented Section

摘要

The section area, the resistance attenuation, the load ratio and the ratio of the longitudinal reinforcement need be taken into account as parameters in the reliability analysis of beams strengthened with augmented section. In this paper, a limit state equation was developed to calculate the ultimate bearing capacity of symmetrical reinforced concrete beams. Monte Carlo method was employed to calculate the reliability of beams reinforced with increasing section area. The effects of resistance degradation, load ratio and ratio of longitudinal reinforced on the reliability of three beam sections were studied as well. The results show that: (1) the reliability index is significantly affected by the section area when the ratio of longitudinal reinforcement is higher, while the reliability index is marginally affected by the section area when the ratio of longitudinal reinforcement is low. (2) The reliability index decreases with the resistance attenuation and load ratio. (3) The relationship of the reliability index and the ratio of longitudinal reinforcement is affected by the initial reinforcing steel bar of the beams.