EFFECT OF THE RESIDUAL STRESSES ON THE SLOW CRACK GROWTH

Posters # 2012 Barcelona

Using linear elastic fracture mechanics a new methodology for a lifetime assessment of internally pressurized polymer pipes was developed. The concept is based on the numerical calculation of stress intensity factors for pipes under different loading conditions in combination with experimentally determined creep crack growth kinetics. The main aim of the work is to estimate the effect of residual stresses on the creep crack kinetics. Based on FEM calculations, the evolution of a creep crack in the case of internal pressure loading taking into account residual stresses, is obtained. An approximate equation for the stress intensity factor in the pipe with residual stresses is presented and good agreement with the numerically obtained data is found. The results and methodology presented can be a powerful tool for estimation of a plastic pipe’s lifetime.

Please note that the whole article content is available on PPCA website onlySource : 2012 Barcelona


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