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The paper discusses the seismic behaviour assessment of a masonry clustered building, which is a prevalent typology in historical centres, particularly focusing on a case study located in a small town in Southern Italy. Following the introduction about the historical centre, the main architectural and structural features of the selected aggregate are outlined, based on the CARTIS Form, which was developed as part of the DPC – ReLUIS Italian research project. After establishing the characteristics of the building, its seismic assessment is conducted. Non-linear analyses reveal inadequate seismic behaviour in both longitudinal and transverse directions. A consolidating intervention which foresees the application of a seismic coating system is proposed. This integrated approach aims to improve both the seismic and energy performance of the aggregate. In the final part of the work, a comparison is made between the results obtained before and after the intervention. This includes the evaluation of the seismic safety index, as well as the examination of the fragility curves. The objective is to assess the effectiveness of the coating system on the structural units of the aggregate, thereby determining the overall improvement in seismic performance following the intervention.

The seismic vulnerability assessment of monumental buildings is a complex task. Several uncertainties mine the reliability of evaluations. Within historical buildings, churches appear as particularly vulnerable objects, prone to instabilities and collapse when undergoing seismic loads. Global and local collapse mechanisms related to in plane and out-of-plane response of walls, respectively, are commonly observed in existing masonry buildings subjected to a seismic event. The main cause is the lack of strong connections among orthogonal walls and between walls and floors, which does not allow a global box-type behaviour of the building. This paper shows an approach to evaluate the vulnerability of churches based on a three-step analysis with increasing detail. The first step is a large-scale analysis to be applied to sets of churches, based on a simplified form comparing 28 mechanisms that can be activated by seismic events. The second step is referred to the evaluation of single churches and related, based on a kinematic approach, to the possibility to have out-of-plane mechanisms. The third step is based on the results of numerical models. It is useful to evaluate the behaviour in detail of some macroelements and to validate the obtained results in the first two steps. [ABSTRACT FROM AUTHOR]

A large percentage of existing building stock in Italy and throughout Europe is ageing and no longer complies with current regulations, particularly in terms of sustainability. For these reasons, an urgent consolidation plan is needed to ensure an increase in both seismic response and energy response. Indeed, these constructions were built before the actual technical codes, and currently, they are not able to withstand seismic actions. Meanwhile, they are subject to thermal dispersions that could be due to the use of materials with poor properties or construction errors. Among the numerous consolidation techniques, an innovative solution consisting of a coating system has appeared on the construction market in recent decades. It is an integrated solution that simultaneously improves the seismic and energy behaviour of the building. The paper proposes the evaluation of this lightweight and sustainable solution through some experimental tests which were performed at the National Institute for Research and Development in Constructions, located in the city of Timişoara (Romania). The tests were aimed to investigate the out-of-plane behaviour of a masonry wall (1.20 m × 2.40 m × 0.60 m) obtained by combining two smaller panels with mortar and subjecting them to constant vertical force and pushing by an increasing horizontal one. Its response was assessed before and after the application of extruded aluminium alloy base profiles belonging to the system under study. [ABSTRACT FROM AUTHOR]

Incremental sheet forming represents a relatively recent technology, similar to the layered manufacturing principle of the rapid prototype approach; it is very suitable for small series production and guarantees cost-effectiveness because it does not require dedicated equipment. Research has initially shown that this process is effective in metal materials capable of withstanding plastic deformation but, in recent years, the interest in this technique has been increasing for the manufacture of complex polymer sheet components as an alternative to the conventional technologies, based on heating–shaping–cooling manufacturing routes. Conversely, incrementally formed polymer sheets can suffer from some peculiar defects, like, for example, twisting. To reduce the risk of this phenomenon, the occurrence of failures and poor surface quality, a viable way is to choose toolpath strategies that make the tool/sheet contact conditions less severe; this represents one of the main goals of the present research. Polycarbonate sheets were worked using incremental forming; in detail, cone frusta with a fixed-wall angle were manufactured with different toolpaths based on a reference and a stair strategy, in lubricated and dry conditions. The forming forces, the forming time, the twist angle, and the mean roughness were monitored. The analysis of the results highlighted that a stair toolpath involving an alternation of diagonal up and vertical down steps represents a useful strategy to mitigate the occurrence of the twisting phenomenon in incremental formed thermoplastic sheets and a viable way of improving the process towards a green manufacturing process. [ABSTRACT FROM AUTHOR]

The aim of this paper is to establish a valid procedure for better understanding all of the phenomena associated with the high-speed machining of glass fiber-reinforced plastic (GFRP) composites. Both rectangular and circular specimens were machined at high cutting speeds (up to 50 m/min) in order to understand what occurred for all values of fiber orientation angles during machining operations. An innovative testing methodology was proposed and studied to investigate the phenomenon of burr formation and thus understand how to avoid it during machining operations. To this end, the forces arising during the machining process and the roughness of the resulting surface were carefully studied and correlated with the cutting angle. Additionally, the cutting surface and chip morphology formed during cutting tests were examined using a high-speed camera. Close correlations were found between the variations in the cutting forces' signals and the trends of the surface roughness and the morphology of the machined surface. [ABSTRACT FROM AUTHOR]

Vertical sun control and shading devices such as louvers are essential features of modern building design. These devices are being used increasingly in the Middle Eastern region due to the extreme temperatures. These devices reduce building peak heat and cooling requirements and enhance indoor natural light. However, it is important to assess these devices so that they meet specific structural strength and serviceability criteria, because if they start to deform, discomfort for the tenants could result. Such deformation might even cause damage to parts of the building, such as the glass windows, especially if this deformation occurs repeatedly over time. An actual case study with aluminum and glass sun control devices was analyzed structurally. Aluminum devices with a twofold height curvature were made from 6-mm-thick curved tubes. They were supported by brackets at various heights with thermal expansion joints for temperature fluctuations. Aluminum devices can withstand 2.0-kPa wind loads, whereas glass fins can withstand loads of 1.8-kPa. The research assessed the induced stresses and deflections through numerical simulations using shell elements. The practical implications of this research indicate that the devices have been proven to be safe within acceptable safety standards and criteria. [ABSTRACT FROM AUTHOR]

Complement inhibition has shown promise in various disorders, including COVID‐19. A prediction tool including complement genetic variants is vital. This study aims to identify crucial complement‐related variants and determine an optimal pattern for accurate disease outcome prediction. Genetic data from 204 COVID‐19 patients hospitalized between April 2020 and April 2021 at three referral centres were analysed using an artificial intelligence‐based algorithm to predict disease outcome (ICU vs. non‐ICU admission). A recently introduced alpha‐index identified the 30 most predictive genetic variants. DERGA algorithm, which employs multiple classification algorithms, determined the optimal pattern of these key variants, resulting in 97% accuracy for predicting disease outcome. Individual variations ranged from 40 to 161 variants per patient, with 977 total variants detected. This study demonstrates the utility of alpha‐index in ranking a substantial number of genetic variants. This approach enables the implementation of well‐established classification algorithms that effectively determine the relevance of genetic variants in predicting outcomes with high accuracy. [ABSTRACT FROM AUTHOR]