GALEOTA, DANTE1; AVOLA, STEFANO2; FANALE, LORENZO3

1) Full professor, University of L’Aquila, Department of Civil Engineering, dante.galeota@univaq.it;

2) Phd student, University of L’Aquila, Department of Civil Engineering, stefanoavola.83@gmail.com;

3) Assistant researcher, University of L’Aquila, Department of Civil Engineering, fanalelorenzo@yahoo.it.

Sant’Apollonia Bridge was built in L’Aquila in 1887 as a connective element between the railway station and the old city center. Realized in crafted stone blocks and bricks, the Sant’Apolonia bridge reflects both architecturally and technically, a typical masonry model encoded by the nineteenth-century’s typical and well-consolidated structural manuals.

After the earthquake of 2009, during which the bridge suffered only slight damages, it immediately acquired a strategic importance for the heavy vehicular traffic needed both for the post emergency management and the reconstruction. In order to plan any structural repair, it has immediately became important understanding which was the most severe effect between the traffic loads and the seismic activity.

Thus, the aim of this study was to provide a deep knowledge connected to the particular details of this bridge by analyzing the available historical documentation; operating a geometric survey with laser scanner; executing a variety of experimental tests able to define the mechanical properties of all construction materials, running dynamic testing and adequate geological investigations

The detailed structural investigation allowed the creation of a F.E.M. model, adequately rated also to consider the dynamic interaction between the underlying soil and the structure itself.

Finally, in 2013 the bridge was tested with ten 35-ton trucks. Using the finite element model researchers were able to hypothesize the deformation pattern of the whole bridge at each single load cycle. The comparison between theoretical predictions and experimental findings confirmed the reliability of the finite element modeling method. The last one proved to be a valid tool, able to accurately verify the design both of the consolidation and the seismic retrofitting.

Keywords: masonry bridge, experimental test, seismic analysis, retrofitting system