Seismic stability assessment of an ancient dry stone defensive wall

Abstract

This paper presents a sophisticated numerical investigation of the seismic stability of a ruinous section of the city walls of ancient Messene (Peloponnese, Greece), which has been recently proposed to be partially but extensively restored. The examined structure corresponds to the proposed restoration. 3-D numerical analyses were performed using the FE software Abaqus and records of four earthquakes suitably scaled. The analyses included, among others, an investigation of the influence of the monument’s rubble core on its seismic response. The numerical results showed that if the monument presents, after its restoration, all the basic conditions favourable for its stability (i.e. solid base, practically vertical outer and inner masonry faces, intact or restored stone-blocks in good contact, gradual formation of the courses at the ends of the masonry faces), it will withstand seismic actions of equal or higher levels than the ones the Seismic Code imposes for the design of the new buildings in the area. Furthermore, the results indicated that as much as the restoration expands (leading for the structure to be closer to its complete, original form), so much higher the seismic stability of the monument will be, provided that the aforementioned conditions will still apply.