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The damage behaviour of unfired dry earth is determined experimentally under compression by means of loading-unloading cyclic tests. The scalar damage parameter is determined and its evolution law is related to the applied strain -d ( ). Interpolating functions are determined, permitting to estimate how the damage depends on the deformation process of the considered material. Different aspect-ratios of the specimens are considered.

Urban seismic networks are considered very useful tools for the management of seismic emergencies. In this work, a study of the first urban seismic network in central Italy is presented. The urban seismic network, built using MEMS sensors, was implemented in the urban district of Camerino, one of the cities in central Italy with the greatest seismic vulnerability. The technological choices adopted in developing this system as well as the implemented algorithms are shown in the context of their application to the first seismic event recorded by this innovative monitoring infrastructure. This monitoring network is innovative because it implements a distributed computing and statistical earthquake detection algorithm. As such, it is not based on the traces received by the stations from the central server; rather, each station carries out the necessary checks on the signal in real time, sending brief reports to the server in case of anomalies. This approach attempts to shorten the time between event detection and alert, effectively removing the dead times in the systems currently used in the Italian national network. The only limit for an instant alarm is the latency in the tcp/ip packages used to send the short reports to the server. The presented work shows the infrastructure created; however, there is not enough data to draw conclusions on this new early warning approach in the field, as it is currently in the data collection phase.

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The reuse of ancient ceramic fragments in Romanesque masonries was a common practice\ud in the Medieval era. A cultural impoverishment of the masonry building art characterized\ud this period. Pre-existing structures were often exploited to build new masonries, both for\ud civil and religious purpose. Starting from these general considerations, a specific construction\ud technique of some Romanesque masonries of the Church of S. Maria in Portuno (Italy)\ud and made by tile and brick fragments, was studied by a multidisciplinary approach. Analyses\ud of the chemical, physical, and mechanical properties of the original materials (tile and brick\ud fragments, mortars) were carried out by laboratory tests. Furthermore, some wall specimens\ud were reproduced through the same ceramic materials and construction technique of\ud the original masonries. Compression tests were carried out on these wall specimens so as\ud to understand the influence of this construction technique on their compressive strength,\ud Young’s modulus, and failure mode. The results allowed increased current knowledge on\ud historical materials and on the mechanical behavior of these specific historical masonries.\ud Useful data obtained by experimental characterization of the materials and walls will also\ud allow to guide future restoration works on these masonries

Hybrid steel and concrete seismic‐resistant systems made by steel frames with reinforced concrete infill walls (SRCWs) have potential advantages over structural solutions made only by steel or reinforced concrete (RC). In fact, the high initial stiffness of concrete is useful to minimize the damage of non‐structural elements under frequent (low to moderate) earthquakes while the ductility and dissipative capacity of the steel allow good performances under rare (high‐intensity) events. Eurocode 8 considers SRCW systems to behave essentially as RC walls. However, numerical analyses on SRCWs, designed according to the Eurocodes, pointed out an unsatisfactory seismic behaviour with discrepancies between the behaviour assumed in the design and the simulated response under seismic actions. Indeed, the idea of stiffening a steel frame with a RC infill leads complex mechanisms that are difficult to control as being affected by many variables. In this study, some of the recent developments made for innovative SRCW are transferred to hybrid steel and concrete walls with partially‐prefabricated infills. Numerical models are analysed to understand the global behaviour of the considered SRCWs and to provide a preliminary validation of the proposed structural solution.

The paper presents the results of research carried out by an interdisciplinary team at the SAD in Ascoli Piceno in collaboration with MiBACT to verify the seismic safety of national museums. The object of study was the Rocca Roveresca Fortress complex in Senigallia (Marche, Italy), a unique example of a small 14th-century fortress shaped by a series of successive modifications. It currently houses a national museum. An integrated survey based on the acquisition of 3D laser-scanner data and endoscopic investigation was necessary to outline the traces of the stratifications and therefore to obtain different highand low-poly 3D models useful for different purposes. The main objective was to propose an ideal workflow in developing 3D models that are useful for finite element method (FEM) analysis to detect hidden vulnerabilities in the fortress by evaluating the behaviour of several substructures in the walls.