The conservation and safety assessment of old masonry arch bridges represent nowadays a
research field of considerable interest. Most of them are testimonies of the past with a significant historical
and cultural value, and represent nowadays a large part of the transport infrastructures serving strategic
link for roads and railways networks. In many cases their masonry primary elements are already
deteriorated due to weather conditions and to the effects of cyclic traffic loads that are increased in both
the frequency and the intensity with respect to the past. Even if the ultimate load is not reached, the
cumulated damage along with the localised deterioration can reach levels not acceptable leading the entire
structure out of service.
This paper is addressed to the fatigue assessment of old masonry arch bridges with particular attention to
the residual service life evaluation of the arch elements. Unlike of metals and metallic structures, little
informations are available to date on the fatigue behaviour of masonry elements, also confirmed by the
fact that there are no specific guidelines for assessing the fatigue limit and the residual life. The paper at
first shows a critical review of the damage models for the fatigue performance assessment of masonry arch
bridges. Then, an application to a case study is presented, where also the influence of intradosal C-FRP
reinforcement on the residual service life and the ultimate capacity is discussed