Gabriele Fiorentino

Damage patterns in the town of Amatrice after August 24th 2016 Central Italy earthquakes

The impact of the two seismic events of August 24th 2016 on the municipality of Amatrice was highly destructive. There were 298 victims, 386 injured, about 5000 homeless, and the historical center of the town suffered a great number of partial and total collapses. The 260 strong motion records obtained for the first event were analyzed and plotted in a shakemap, comparing them with the macroseismic damage surveys made in 305 localities. On the basis of an inspection survey made in September 2016, a map of the damage patterns of the buildings in the historical center was elaborated according to the EMS 98 classification. The damage level resulted very high with more than 60% of the inspected buildings showing partial or total collapse. The elevated level of destruction was mainly caused by the high vulnerability of the masonry buildings, mostly due to specific vulnerability factors such as the poor quality of masonry, the lack of connections between walls and the poor connection between external walls and floors.

Behavior of the Leaning Tower of Pisa: Analysis of Experimental Data from Structural Dynamic Monitoring

Understanding the structural behavior of heritage buildings is usually a very complicated task because they typically present complex deterioration and damage patterns which cannot be fully evaluated by means of visual inspections. Moreover, the reliability of such constructions largely depends on different materials, structural components and details, the health of which is often unknown or affected by great uncertainties. In this regard, the experimental dynamic testing of heritage buildings and monuments subjected to ambient vibrations has become a valuable tool for their assessment because of the minimum interference with the structure. Traffic-induced vibrations are not always a feasible dynamic load for monumental buildings due to their very low intensity or owing to existing restrictions to road and rail traffic. On the other hand, the analysis of the experimental response under earthquakes can lead to more relevant information about the dynamic behavior of historic constructions, provided that the structure is equipped with a permanent sensor network. Within this framework, the present work illustrates preliminary results carried out from time and frequency domain analyses performed on the experimental dynamic response of the leaning tower of Pisa using seismic records. The main dynamic features of the monument have been identified, and then examined taking into account the seismic input and the soil-foundation-structure interaction.

PROBABILISTIC EVALUATION OF DAM BASE SLIDING

Concrete gravity dams represent a relevant part of the 500 large dams existing in Italy. Most of them were built following obsolete seismic design criteria, so they need to be verified with modern seismic analyses according to the new Italian Code on Dams (2014). Many of the parameters utilized in this evaluation are affected by large uncertainties. In the paper we present a procedure based on Monte Carlo simulation which evaluates the probability of exceedance of the sliding equilibrium of the dam obtained via static or response spectrum analysis in case of seismic action, as well as the probability of exceedance of different sliding displacements via nonlinear dynamic analyses. The application to four seismic sites (of different seismic hazard) and to three dams with different heights is presented.