Effect of temperature on CFST arch bridge ribs in harsh weather environments

In a concrete-filled steel tube (CFST), dry shrinkage and creep produce a circumferential gap between the inner concrete core column and outer steel tube that is increased by harsh weather in cold regions. Thermomechanical coupling finite element analysis was performed to determine the temperature fields, stresses, and strains of CFST arch bridge ribs with circumferential gaps. A traction–separation law was developed for cohesive elements of the steel–concrete interface, which was applied to a parametric analysis on the CFST temperature field and stresses according to diameter. The results can help guide maintenance strategies for CFST arch bridges.