Effect of spatial variation and possible interference of localised corrosion on the residual capacity of a reinforced concrete beam

Abstract

While much numerical and experimental work has progressed to assess the structural performance of corrosion damaged RC beams, there is to the authors’ knowledge no work on numerical analysis considering spatial variation and possible interference of localised corrosion.

This PhD thesis is focusing on the structural impact of reinforcement corrosion in RC beams. The effect of spatial distribution and possible interference of localised corrosion on the bending ultimate limit state (ULS) was studied in detail through numerical, analytical and statistical analyses.

Numerical results show that the interference of pits on adjacent rebars leads to a gradual reduction of the bending ULS for decreasing distances between the pits, starting at a critical distance. Based on the obtained results, a modified analytical design rule was suggested to calculate the residual ULS by taking into account the ratio of pit distance in longitudinal direction on adjacent bars to rebar distance. The Monte-Carlo simulation was performed to quantify the effect of the interference of pits on the probability of failure. The results indicate that pit interference has significant influence on the probability of failure of corroded under-reinforced beam. The results of two practical methods to account for spatial variation and interference of localised corrosion are compared with the current results to highlight the role of empirical coefficients in these practical methods.