A Review of Prediction Methods for Ultra-Low Cycle Fatigue Damage of Steel Piers Under Earthquakes

Abstract

Steel bridge piers are vulnerable to seismic damage, with ultra-low cycle fatigue commonly occurring at the base of the piers or at welded joints under strong earthquake conditions. The current methods for predicting ultra-low cycle fatigue in steel bridge piers include the empirical formula method, the cyclic void growth model (CVGM), and the continuous damage mechanics (CDM) model. This paper reviews the principles, development, advantages, and limitations of these three prediction methods. Compared to the empirical formula method, the CDM model offers improved accuracy for predicting ultra-low cycle fatigue life in welded joints under complex stress conditions. Unlike the CVGM, the CDM model requires fewer calibration tests, directly incorporates the effects of damage on material properties, and integrates well with finite element software. These benefits highlight the potential of CDM-based prediction methods for practical application.

Keywords

• bridge piers
• strong earthquake
• ultra-low cycle fatigue
• prediction method for damage
• continuum damage mechanics