1,226 research outputs found

    AN HISTORICALLY-INFORMED APPROACH TO THE CONSERVATION OF VERNACULAR ARCHITECTURE: THE CASE OF THE PHLEGREAN FARMHOUSES

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    Abstract. Landscape is always the object of countless mutations: some of them disrupt its identifying features; others leave intact its original traits. Vernacular architecture is linked closely to the vocation of its landscapes, especially agricultural ones: this is the case of Pianura, a neighbourhood in the Phlegrean western suburban area of Naples, where the remains of vernacular architecture and its connections to agriculture are still traceable among the unstoppable process of building speculation which, since the 1960s, has torn up the rural fabric. In this uncontrolled development of the modern city, the architectural heritage of the farmhouse has shown its resilience: although parts of it appear to have been completely engulfed by the uncontrolled expansion of the city, in as many cases farmhouses have endured time, degradation, and indifference towards their historical value. In the heart of the neighbourhood, the masseria, with all its recurring features, remains the most widespread housing model, despite more recent interventions. Through the study of the history and architectural features of Masseria S. Lorenzo, this contribution aims to identify possible guidelines and strategies for the conservation of the material and immaterial values of these examples of vernacular architecture, putting them on a restoration and re-functionalisation path that is mindful of their past heritage and future potential

    Earthquake Early Warning System for Structural Drift Prediction Using Machine Learning and Linear Regressors

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    In this work, we explored the feasibility of predicting the structural drift from the first seconds of P-wave signals for On-site Earthquake Early Warning (EEW) applications. To this purpose, we investigated the performance of both linear least square regression (LSR) and four non-linear machine learning (ML) models: Random Forest, Gradient Boosting, Support Vector Machines and K-Nearest Neighbors. Furthermore, we also explore the applicability of the models calibrated for a region to another one. The LSR and ML models are calibrated and validated using a dataset of ∼6,000 waveforms recorded within 34 Japanese structures with three different type of construction (steel, reinforced concrete, and steel-reinforced concrete), and a smaller one of data recorded at US buildings (69 buildings, 240 waveforms). As EEW information, we considered three P-wave parameters (the peak displacement, Pd, the integral of squared velocity, IV2, and displacement, ID2) using three time-windows (i.e., 1, 2, and 3 s), for a total of nine features to predict the drift ratio as structural response. The Japanese dataset is used to calibrate the LSR and ML models and to study their capability to predict the structural drift. We explored different subsets of the Japanese dataset (i.e., one building, one single type of construction, the entire dataset. We found that the variability of both ground motion and buildings response can affect the drift predictions robustness. In particular, the predictions accuracy worsens with the complexity of the dataset in terms of building and event variability. Our results show that ML techniques perform always better than LSR models, likely due to the complex connections between features and the natural non-linearity of the data. Furthermore, we show that by implementing a residuals analysis, the main sources of drift variability can be identified. Finally, the models trained on the Japanese dataset are applied the US dataset. In our application, we found that the exporting EEW models worsen the prediction variability, but also that by including correction terms as function of the magnitude can strongly mitigate such problem. In other words, our results show that the drift for US buildings can be predicted by minor tweaks to models

    Manufacturing and Validation of a Novel Composite Component for Aircraft Main Landing Gear Bay

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    Composite materials may reduce the final weight of the aircraft structural components, in addition to improve fatigue performance and corrosion resistance. In order to achieve the optimization of air transport systems, making them increasingly sustainable, the structural design must be surely reviewed, starting to follow the ‘‘composite thinking’’ philosophy. The present research provides some relevant outcomes concerning the design of a composite sample for the main landing gear bay of a large commercial airplane (EASA CS25 category), within ITEMB (integrated full composite main landing gear bay concept) project, a program of Clean Sky 2 EU research framework. The most ambitious goal is to develop a new generation of lower center fuselage (LCF) with an innovative integrated landing system in the fuselage, which is considered the next frontier in the development of landing systems for medium-haul aircraft, such as the Airbus A320 aircraft family. The development of a different architecture, with the landing gear integrated within the related fuselage bay, could lead to a simplification of the whole subassembly with potential advantage in terms of construction and assembly times. Final target of the project is the manufacturing of an innovative monolithic composite structure that will replace the actual configuration (a mixed structure of metal and composite subassemblies) reducing or actually removing all the cost of assembly and increasing the production rate. This paper presents the main results of the work, introducing the main processing steps and prototype results; in the last part of the work, also some experimental tests on significant element are introduced as the first assessment of the technology readiness level that has been achieved
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