Effect of Corrosion-Fatigue Coupled Damage on Mechanical Properties of Q345 Angle Steel

摘要

Atmospheric environmental corrosion and wind-induced fatigue achieve a long-term synergistic effect, mutual coupling and promotion with each other. Under this circumstance, the speed of structural performance degradation accelerates and the ability of the structure to resist accidental loading decreases. In this paper, an evolutionary model for evaluating fatigue damage is established based on the characteristics of energy dissipation and fatigue crack propagation. Meanwhile, a corrosion damage model is established based on basic mechanical parameters. Then a coupling factor is deduced to evaluate the correlation between corrosion damage and fatigue damage, and the corrosion-fatigue coupled damage model is established by using this coupling factor. Finally, a quasi-static test of Q345 angle steel is conducted to study the failure modes, the hysteresis curve and the variation of main performance evaluation parameters under three test conditions, and a corresponding coupled damage performance degradation model is established.