This work presents a numerical simulation of the church of San Francesco, Amatrice, and subsequent interpretation of the evolution of damage and collapse mechanisms that were caused by the main events of the seismic sequence that hit the Apennine area of Central Italy in 2016. The study primarily focuses on the response of the church with reference to the two main events: seismic shocks of 24th August and 30th October 2016. The dynamic non-linear analysis was performed on the structure using Abaqus CAE 2017, which was intended at simulating the damage and collapse that were observed on the real structure subsequent to the main seismic events. The study also contributes to suggest preventive interventions/material enhancements that could have either limited or mitigated the damage, thereby avoiding the collapse of the Church. In an effort to reciprocate the seismic events, the time-history of the accelerograms recorded at the AMT fixed station and of the amplified local accelerogram were considered as seismic input. Furthermore, this study presents simulations of the response of the structure subjected to the main seismic events simulated in a continuous chronological sequence and the effects of local and global interventions on the seismic response of the entire structure. This study indicates the application of numerical simulation as an efficient tool for seismic analysis of masonry structures, with the obtained results ranging within the acceptable margin of errors. In addition, the simulations can be used to analyse the proposed interventions, while taking into account the limitations of the software and computational techniques. This paper highlights the interesting conclusions related to the effects of local and global interventions in case of the church of San Francesco and the role of amplification of the accelerations for the site of Amatrice.@en

The problem of seismic safety assessment is discussed with reference to the case of an historical reinforced concrete bridge; specifically, a bridge located in Songavazzo, Italy across the Valeggia river, completed in 1911. Experimental testing has been performed, providing all the required information for the identification of the dynamic behaviour. Seismic vulnerability has been evaluated with both response spectrum modal analyses and nonlinear static (push-over) analyses as well. The bridge response is compared to the one obtained for a similar bridge yet reflecting a different structural scheme. Structural analyses have allowed to highlight different structural concepts while, on the other hand, they show the complementary nature of the two bridges. In both cases, reinforced concrete arches are mainly subjected to axial loads and provide the main structural system.@en

This work is aimed at the numerical interpretation of the evolution of damage and collapses observed on the Civic Tower of Amatrice, caused by the main events of the seismic sequence of 2016 in the Apennine area of Central Italy. In particular, the study considers the response of the tower with reference to the two main events, occurred on August 24th and October 30th, 2016 respectively. Non-linear dynamic analyses were carried out by developing a finite element model and the behaviour of the tower was investigated with reference to the damage and partial collapses produced by the main events. In dynamic numerical analyses, the accelerograms corresponding to the main seismic events obtained with the study of the site effects were used as seismic input. Moreover, studies have been carried out to understand if and which of the interventions of reinforcement/seismic improvement, realized at the beginning of the years ‘80, have been determinant to limit the damage, avoiding the complete collapse of the tower. The results of the study, on the one hand, allow to highlight a good correspondence between the evolution of the actual damage observed on the tower and the damage assessed by numerical analyses thus demonstrating the validity of the numerical models set up for the analyses. On the other hand, however, they have made it possible to underline how the presence of the improved material and structural reinforcement interventions carried out at the beginning of the years ‘80 have contributed to avoid the complete collapse of the tower.@en