Tracking Evidence of Seismic Damage by Nonlinear Numerical Simulations for Dating in Archaeological Contexts

Abstract

The Roman town of Ostia offers a unique opportunity to study a wide range of structural damage affecting different types of ancient buildings. In the Piccolo Mercato, potential seismic effects are visible in the masonry walls and in some of the masonry pillars that in ancient times supported an arcade. This paper, with the aim of providing insight into the causes of the observed damage on one of these pillars, reports and discusses some results of an interdisciplinary study. The damaged pillar under consideration, in particular, is today broken with the upper part rotated about 12 degrees counterclockwise from the lower part. Numerical simulations of this pillar have been performed using finite element models, and incremental nonlinear time-history analyses were carried out for quite a large number of seismic input ground motions. From the obtained results, it appears that a rotation, similar to that exhibited by the upper part of the pillar, can be attributed to seismic action with Peak Ground Acceleration (PGA) values ranging from medium to high.