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The present study concerns the structural analysis of the masonry vaulted stairs of the Santa Maria delle Vigne bell tower in Genoa (Italy). The vaulted staircase systems are fully analysed in terms of technological and constructive details. The 3D geometric models are defined from laser scanner data. The structural analyses were carried out by using both the equilibrium limit analysis and a static incremental FEM analysis. Despite the efficacy of classic equilibrium methods in analysing arched and vaulted structures is largely proved in literature, this study demonstrates that vaulted staircase systems often collapse because of compressive failure of masonry before losing stability.

The concept of vulnerability of the existing building stock is receiving increasing awareness and central importance in the scientific community working in earthquake risk mitigation. This assumes even more relevance when dealing with heritage structures located in relevant seismic hazard zones. This paper aims to identify and describe the earthquake-resistant features found in a unique masonry church in Ischia (Italy), and discuss their effectiveness on the impact of the post-seismic damage through the application of non-linear static analyses. The Santa Maria Maddalena Church represents one of the rare examples in which the technology of the Borbonic casa Baraccata (mixed timber−masonry construction), already well-known in the literature for its use in Italian seismic areas since the eighteenth century, is applied with the non-conventional combination of masonry and iron frames. The church was struck by the recent earthquake of 21 August 2017 with epicentre in Casamicciola Terme. The recorded post-seismic damage of the church evidenced non-relevant structural crack patterns, which are likely to be related to the efficacy of the construction system adopted.

Preprint version, The implementation of a culture of seismic risk preparedness is becoming increasingly critical in Europe as the building stock ages and the awareness about seismic risk rises. In this context, the assessment of the seismic vulnerability of existing buildings, followed by the implementation of appropriate retrofitting solutions, can help to substantially reduce the levels of physical damage and economic impact of future events. The central region of Portugal is particularly susceptible to large seismic events and is characterized by the prevalence of historic masonry buildings. This work aims to validate assessment methods for the risk of historical city centers in order to propose management strategies for municipalities and assess the economic impact of large-scale seismic retrofitting. To do this, an application of these methods was performed on the historical city center of Leiria. An in-depth inspection was performed of the entire center and the results were compiled into a database. Using an index-based seismic vulnerability assessment approach, a vulnerability assessment was made for each building. Based on vulnerability and predicted damage, estimates of human and economic losses were made for the city center before and after retrofitting to justify interventions on a broad scale., This work was enabled and funded by the Advanced Masters in Structural Analysis of Monuments and Historic Constructions (SAHC) at the University of Minho and by the Portuguese Foundation for Science and Technology (FCT) through the postdoctoral fellowship SFRH/BPD/122598/2016. The authors would like to thank the students at the Polytechnic Institute of Leiria for their assistance in coordinating and executing fieldwork. Additionally, many thanks to the Municipality of Leiria for providing access to their records and support of the work.

As a result of several impactful events, the focus of the international community on the effects of natural hazards in urban areas has been increasing in recent years. The framework for research and innovation on urban risk reduction and urban resilience is presently defined by several technical and societal challenges at different levels. In fact, urban risk is a very complex multi-dimensional matrix that can involve multiple elements at risk, multiple hazards, multiple temporal scales, and multiple sources of vulnerability. Understanding the impacts and interactions between these elements is an essential step towards the development of more effective risk reduction strategies, particularly in historical city centers, which, due to their characteristics, are even more demanding. Within this framework, the present paper takes advantage of a large-scale seismic vulnerability assessment method, specially developed to assess the vulnerability of masonry facade walls, to evaluate the vulnerability and to develop damage scenarios for the Historic City Center of Leiria. Based on these scenarios, obtained for the relevant seismic intensities of the region, a variety of probabilistic-based outputs related to emergency planning (inaccessible urban areas, isolated people, and possible evacuation routes) were generated and comprehensively discussed. Finally, the potential benefit resulting from the application of different seismic retrofitting strategies is also investigated, both in terms of expected damages and evacuation scenarios.

To estimate the matching between the backs of adult Talitrus saltator and the sand from their home beaches, reflectance, and patch shape and size were measured. Results show that in general there is a good matching between sandhopper back patterns and the local sand. Captivity caused a significant difference in the degree of similarity between the animals’ patterns and the sand. In spite of the good level of crypsis, some behavioural data suggest that it is not sufficient to protect the sandhoppers from predation (e.g., by shore birds and shallow water fishes).