Application of Probabilistic Approach to Investigate Influence of Details in Time History of Temperature Changes on the HCF Life of Integrated Bridge Steel Piles Installed on Water

This research estimates the high-cycle fatigue (HCF) life of integrated concrete bridge installed on water due to temperature changes. To this end, CATIA software was used geometrically model a real-scale bridge. Next, thermal–structural coupling analysis performed by finite element (FE) simulation in ANSYS WORKBENCH software. The comparison technique with experimental data validate simulation. Afterward, thermal air changes different modes, including average monthly (large variations) as well maximum and minimum (small variations). results showed that most deck length subsequent deviation upper part steel piles were related three warm seasons presence water. Eventually, probabilistic approach employed find variable amplitude lifetime component based number annual loading blocks. achieve high-accuracy response, effective parameters proposed approach, order Fourier series stress range, optimized automatically. In addition, obtain HCF behavior raw material, axial tension–compression tests standard specimens fabricated from piles. revealed considering small variations calculation structural led 550% reduction compared large variations. obtained results.