Experimental and numerical study on ultimate strength of steel tubular members with pitting corrosion damage

Pitting corrosion can cause stress concentration and early onset of plasticity in the metallic structural components. This paper presents a comprehensive experimental and numerical study on the effect of pitting features such as pit shape and depth, pitting distribution and intensity on the structural performance of steel tubular members. The experimental investigations were carried out on tubular members with mechanically drilled pitting damage under axially loaded compression condition. The test results were applied to validate finite element (FE) models by comparing the load-shortening curves, ultimate loads and failure modes. The validated FE models were then used to simulate the random nature of pitting damage in terms of stochastic simulation. The results from the stochastic analyses show that random natures associated with pit shape, pit depth and pitting distribution can result in a great reduction and variation of ultimate strength, likely causing the transition of collapse mode. The experiments provide a modelling benchmark to validate FE models of the tubular structures with random pitting corrosion for the ultimate strength assessment. The developed FE models are shown to be capable of replicating the pitted tubular members.