Structural History of the Colosseum, Rome

The Flavius Amphitheatre was dedicated and opened to the public in 80 AD during the reign of Titus, probably while still under construction. In its present state, in order to ensure durability and stability, the Colosseum needs strengthening on two fronts. The first effort should be to arrest the deterioration and negative effects produced by the misalignment and displacement of masonry blocks, consequences of strong earthquakes of the past. The second is linked to the general seismic risk factor of Rome and the probability that another strong earthquake can occur in the future. In such an event, it is very likely that another part of the monument, in particular the two abutments of Stern and Valadier, could reach a critical situation, as the preliminary calculations have indicated.