evaluation of seismic capacity of plain concrete arch bridges based on stress intensity factor

There are numerous old arch bridges in iran that have been used as railway bridges for more than 80 years. since most of these bridges are not designed for earthquake excitation, seismic vulnerability of these structures is uncertain.this fact necessitates the investigation of the earthquake resistance of these kinds of bridges. for this purpose, nonlinearstatic analysis (pushover method), non-linear dynamic analysis (ida method) have been used frequently toassess the remaining capacity of plain concrete arch bridges (mahmoudi et al., 2018; marefat et al., 2019). this work is aimed to assess the seismic capacity of plain concrete arch bridges which are suffered cracks based on a new aspect. for the cracked domains it seems the most perfect method to evaluate them relate to fracture mechanics theory.