Multi-scale fatigue damage model for steel structures working under high temperature

摘要

In order to better understand the fatigue mechanisms of steel structures working under high temperature,a multi-scale fatigue damage model at high temperature is developed.In the developed model,the macroscopic fatigue damage of metallic materials due to the collective behavior of micro-cracks is quantified by using the generalized self-consistent method.The influence of temperature on fatigue damage of steel structures is quantified by using the previous creep damage model.In addition,the fatigue damage at room temperature and creep damage is coupled in the multi-scale fatigue damage model.The validity of the developed multi-scale damage model is verified by comparing the predicted damage evolution curve with the experimental data.It shows that the developed model is effectiveness.Finally,the fatigue analysis on steel crane runway girders (CRGs) of industrial steel melt shop is performed based on the developed model.