The seismic sequence that stroke central Italy in August and October 2016 affected a large number of school buildings. One of these was the elementary school of the town of Visso, a 5000-cubic-metre, two-storey stone masonry building. The Italian Structural Seismic Observatory (OSS), a network of permanent sensors mainly installed in public buildings by the Department of Civil Protection, monitored this school. Twenty-three accelerometric channels allowed recording the dynamic response of the building during the entire sequence, which caused the collapse of portions of masonry walls and floor diaphragms. Double-integration of acceleration time histories provided estimations of displacements and deformations, which can be related to different damage states. A detailed geometric and mechanical characterization of the structural system complemented the data provided by the OSS, allowing the development of a reliable equivalent-frame numerical model of the building, implemented in the software Tremuri. The comparison between data recorded on site and nonlinear time-history analysis results confirmed some of the main modelling assumptions typically validated against smaller shake table experiments.

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The present paper aims at investigating the condensation process inside minichannels, at low mass fluxes, where bigger discrepancies from conventional channels can be expected. At high mass flux, the condensation in minichannels is expected to be shear stress dominated. Therefore, models originally developed for conventional channels could still do a good job in predicting the heat transfer coefficient. When the mass flow rate decreases, the condensation process in minichannels starts to display differences with the same process in macro-channels. With the purpose of investigating condensation at these operating conditions, new experimental data are here reported and compared with data already published in the literature. In particular, heat transfer coefficients have been measured during R134a and R1234ze(E) condensation inside circular and square cross section minichannels at mass flux ranging between 65 and 200 kg m−2 s−1. These new data are compared with those of R32, R717, R290, R152a to show the effect of channel shape and fluid properties and to assess the applicability of correlations developed for macroscale condensation. For this purpose, a new criterion based on the Weber number is presented to decide when the macroscale condensation correlation can be applied. The present experimental data are also compared against three-dimensional Volume of Fluid (VOF) simulations of condensation in minichannels with circular and square cross section. This comparison allows to get an insight into the process and evaluate the main heat transfer mechanisms

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