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This work describes a procedure for building a high-quality 3D model of a rocky pinnacle in the Dolomites, Italy, using Structure from Motion (SfM) techniques. The pinnacle, known as "Campanile di Val Montanaia", is challenging to survey due to its high elevation and sub-vertical cliffs. The construction of the 3D model is the first step in a multi-disciplinary approach to characterize the rock mass and understand its behavior and evolution. This paper discusses the surveying operations, which involved climbing the pinnacle to collect Ground Control Points (GCPs) and using a UAV to capture aerial imagery. The photographs were processed using SfM software to generate point clouds, mesh, and texture, which were then used for rock mass discontinuity mapping. The study compares models of different qualities and point densities to determine the optimal trade-off between processing time and accuracy in terms of discontinuity mapping. The results show that higher quality models allow for more detailed mapping of discontinuities, with some drawbacks due to noise in the case of the densest solution (e.g., increase in frequency of outliers across the point cloud). These pros and cons are also discussed in relation to the computational cost necessary to build the models. The study also examines the limitations and challenges of performing discontinuity mapping in the different models, including subjectivity in interpretation. A further element of interest is the publication of a high-quality 3D georeferenced model of the "Campanile di Val Montanaia" to be used for several potential further applications, such as stability analyses and numerical modeling. [ABSTRACT FROM AUTHOR]

In this paper, a three-dimensional (3D) numerical model based on the finite element method (FEM) is developed to determine the fluid flow and heat transfer phenomena in a real multi-tube downhole heat exchanger (DHE), designed ad hoc for the present application, considering natural convection inside a geothermal reservoir. The DHE has been effectively installed and tested on the island of Ischia, in southern Italy, and the measurements have been used to validate the model. In particular, the authors analyze experimentally and numerically the behavior of the DHE based on the outlet temperature of the working fluid, thermal power, overall heat transfer coefficient, and efficiency. Furthermore, the influence of the degree of salinity on the performance of the DHE has been studied, observing that it degrades with the increase in the degree of salinity. The results show that the DHE allows to exchange more than 40 kW with the ground, obtaining overall heat transfer coefficient values larger than 450 W/m2 K. At the degree of salinity of 180 ppt, a decrease in the efficiency of the DHE of more than 8% is observed. [ABSTRACT FROM AUTHOR]

The paper illustrates the construction of abacuses for the semi-quantitative assessment of stratigraphic seismic amplification phenomena, applicable in the eastern Abruzzo region (central Italy). The abacuses provide three expected Amplification Factors (Fas): Fa0.1-0.5, Fa0.4-0.8, Fa0.7-1.1, performed as the ratio between the integral of output and input, in the mentioned time intervals, considering the acceleration response spectra. The choice derives from the fact that these parameters are better correlated to the response of the buildings, characterised by their own different periods. To prepare the abacuses, a procedure was adopted that took into consideration the geological analysis of the area, the collection of all the available geophysical and geotechnical data, the choice of the seismic inputs representative of the seismic hazard, the identification of the main seismic stratigraphic sequences and the numerical analysis aimed at evaluating the Fa. The abacus consists of a series of tables prepared in order to take account of the stratigraphic variability in the area, as a function of the basic seismic hazard level and the vibration period interval to calculate the Fa. By knowing the stratigraphic and mechanical characteristics of the site and using the abacuses, the values of the Fa are obtained. [ABSTRACT FROM AUTHOR]

This paper deals with precipitation events, particularly the problem of recognising events individually, of distinguishing one local meteorological/precipitation event from another. The final aim was to arrive at a more appropriate conceptualization of "distance" between individual annual events. A criterion for identifying annual precipitation events, inside a 5 min-timestep series of pluviometric data, was proposed. Using this numerical criterion, a series of annual distances between events were obtained and compared with those obtained by other two known and applied statistical methods. This comparison would be important for linking the so-called statistical methods to the real data of the series, analysed through a numerical process. This would make it possible to provide a kind of "measure" for the understanding of real data via a statistical model. Results showed that distances between events, obtained through numerical analyses, are almost always different from those obtained by statistical methods. The supposed Poisson-process, generally matched to, and widely applied in the field of rainfall data, showed some contradiction with the analysis conducted in this paper. The so-called Lag method shows a numerical method type distribution, but produces some important internal deviations from numerical results. It seems that the method proposed in this paper can reproduce the real distances between events more realistically compared to the statistical methods considered here. Exponential distribution does not seem highly performing, at least in the case of the annual analysis, with series of a 5-min time-step resolution, obtained from rain gauges installed in the Veneto Region of Italy. It is believed that the numerical criterion presented in this paper can be considered adequate for determining the distances between events, within an annual time-window. [ABSTRACT FROM AUTHOR]

Industrial single-storey buildings are the most diffuse typology of steel construction located in Italy. Most of these existing buildings were erected prior to the enforcement of adequate seismic provisions; hence, crucial attention is paid nowadays to the design of low-impact retrofit interventions which can restore a proper structural performance without interrupting productive activities. Within this framework, an existing industrial single-storey steel building located in Nusco (Italy) is selected in this paper as a case-study. The structure, which features moment resisting (MR) truss frames in both directions, is highly deformable and presents undersized MR bolted connections. Structural performance of the case-study was assessed by means of both global and local refined numerical analyses. As expected, the inadequate performance of connections, which fail due to brittle mechanisms, detrimentally affects the global response of the structure both in terms of lateral stiffness and resistance. This effect was accounted for in global analyses by means of properly calibrated non-linear links. Thus, both local and global retrofit interventions were designed and numerically investigated. Namely, lower chord connections were strengthened by means of rib stiffeners and additional rows of M20 10.9 bolts, whereas concentrically braced frames (CBFs) were placed on both directions' facades. Designed interventions proved to be effective for the full structural retrofitting against both seismic and wind actions without limiting building accessibility. [ABSTRACT FROM AUTHOR]

The need for a reliable estimate of the actual failure probability of existing river embankments under changing boundary conditions represents an ever-demanding task for researchers and designers, and those involved in their maintenance and management. Uncertainty and variability of soil suction and water content spatial and temporal distributions, together with the definition of a suitable soil model that accounts for the partially saturated state of embankment materials, are among the most critical aspects to be possibly included in the advanced analysis and design of such linear earthen infrastructures. The use of specialist integrated monitoring can be here functional to enable calibration and to enhance reliability and consistency of predictive analyses. Site measurements of the main variables at relevant depths are typically rarely available, whereas an accurate soil characterization under partially saturated conditions is only performed in research applications, thus producing limited confidence on stability conditions. To provide a useful and innovative tool to evaluate realistic stability conditions of levees under transient flow conditions, a full-scale monitoring system has been implemented on an existing section of the River Secchia (northern Italy) 11-m-high flood defenses. The complementary use of specific laboratory tests, innovative field measurements and numerical analyses presented in the paper aims at providing a suitable methodological approach to the performance assessment of these vital geotechnical systems throughout their entire lifetime and highlighting possible limitations of typically used methods of analysis. [ABSTRACT FROM AUTHOR]

The preparation, initiation and occurrence dynamics of earthquakes in Italy are governed by several frequently unknown physical mechanisms and parameters. Understanding these mechanisms is crucial for developing new techniques and approaches for earthquake monitoring and hazard assessments. Here, we develop a first-order numerical model simulating quasi-static crustal interseismic loading, coseismic brittle episodic dislocation and post-seismic relaxation for extensional and compressional earthquakes in Italy based on a common framework of lithostatic and tectonic forces. Our model includes an upper crust, where the fault is locked, and a deep crust, where the fault experiences steady shear. The results indicate that during the interseismic phase, the contrasting behaviour between the upper locked fault segment and lower creeping fault segment generates a stretched volume at depth in the hangingwall via extensional tectonics while a contracted volume forms via compressional tectonics. The interseismic stress and strain gradients invert at the coseismic stage, with the interseismic dilated volume contracting during the coseismic stage, and vice versa. Moreover, interseismic stress gradients promote coseismic gravitational subsidence of the hangingwall for normal fault earthquakes and elastic uplift for reverse fault earthquakes. Finally, the post-seismic relaxation is characterized by further ground subsidence and uplift for normal and reverse faulting earthquakes, respectively, which is consistent with the faulting style. The fault is the passive feature, with slipping generating the seismic waves, whereas the energy activating the movement is stored mostly in the hangingwall volume. The main source of energy for normal faulting and thrust is provided by the lithostatic load and elastic load, respectively. [ABSTRACT FROM AUTHOR]

The dynamic behaviour and the seismic vulnerability of the ancient civic clock tower of Amatrice, dramatically damaged by the last shocks sequence of 2016 that occurred in Central Italy, is studied in this paper by means of advanced 3D numerical analyses with the Non-Smooth Contact Dynamics Method (NSCD). Thus, a discontinuous approach was used to assess the dynamic properties and the vulnerability of the masonry structure, through large displacements regulated by the Signorini’s law, concerning the impenetrability between the rigid bodies, and by the Coulomb’s law, regarding the dry-friction model. Afterward, different values were assigned to the friction coefficient of the models and real seismic shocks were then applied in nonlinear analyses. The major purpose of this study is to highlight that relevant data on the real structural behaviour of historical masonry may provided through advanced numerical analyses. The comparison between the results of numerical simulation and survey of the existing crack pattern of the bell tower permitted to validate the selected approach. Finally, from results and conclusions provided by this case study, it is possible to affirm that the used methodology may be applied to a wide variety of historical masonry structure in Europe. [ABSTRACT FROM AUTHOR]

In this paper, an optimization model is defined for the design of a smart energy infrastructure integrating different technologies to satisfy the electrical demand of a given site. The considered smart energy infrastructure includes a photovoltaic plant, electrical storage systems, electric vehicles (EVs), and charging stations. The objective function of the optimization model considers the costs related to the installation and maintenance of the considered technologies, as well as the costs associated with the energy exchanges with the external grid. A very extensive numerical analysis is reported in the paper, referred to a test case in a real site in Liguria Region, in the north of Italy. Many scenarios are analyzed and discussed, with specific attention to evaluate the role of electric mobility within a smart energy infrastructure and a focus on EVs acting as mobile storage systems. [ABSTRACT FROM AUTHOR]

Stimulated by the recent advances in computational tools for the simulation of seismic wave propagation problems in realistic geological configurations, this paper presents a 3D physicsbased numerical analysis of near-source ground motion during the MW 6.0 2012 May 29 earthquake in the Po Plain, Northern Italy. To reproduce with sufficient accuracy some of the most peculiar features of the near-source strong-motion records and of the spatial variability of damage distribution, this study required a sequence of investigations, starting from the analysis of a wide set of near-source records, to the calibration of an improved kinematic seismic source model, up to the development of a 3D numerical model of the portion of the Po Plain interested by the earthquake. The latter includes the basin geometry, characterized by sediment thickness sharply varying from few tens of metres to some kilometres. The spatial resolution of the numerical model is suitable to propagate frequencies up to about 1.5 Hz. Numerical simulations were performed using the open-source high-performance code SPEED, based on the Discontinuous Galerkin Spectral Elements method. The 3D numerical model, coupled with the updated slip distribution along the rupturing fault, proved successful to reproduce with good agreement, measured through quantitative goodness-of-fit criteria, the most relevant features of the observed ground motion. These include: (i) the large fault normal velocity peaks at the near-source stations driven by updip directivity effects; (ii) the small-scale variability at short distance from the source, resulting in the out-of-phase motion at stations separated by only 3 km distance; (iii) the propagation of prominent trains of surface waves, especially in the Northern direction; (iv) the map of earthquake-induced ground uplift with maximum values of about 10 cm, in substantial agreement with geodetic measurements and (v) the two-lobed pattern of the peak ground velocity map, well correlated with the distribution of macroseismic intensity. [ABSTRACT FROM AUTHOR]

Highlights: [•] A clock tower collapsed during the 2012 Emilia Romagna (Italy) seismic sequence is analyzed. [•] A full 3D Finite Element model obtained after a detailed historical/geometrical analysis is used. [•] Pushover, limit analyses under horizontal loads and full non-linear dynamic analyses are conducted. [•] All approaches confirm the high vulnerability of the structure and the observed collapse modes. [•] The aim of the numerical analyses is to provide detailed information for the reconstruction. [Copyright &y& Elsevier]

Abstract: Three masonry churches collapsed or severely injured during the 20–29 May 2012 earthquakes occurred in Emilia-Romagna, Italy are analyzed in detail from a numerical standpoint. A recently presented standalone 3D limit analysis code is utilized to evaluate failure mechanisms and horizontal acceleration causing the collapse. A comparison with the recent Italian Guidelines devoted to the safety assessment of monumental buildings is also provided. The horizontal acceleration associated to the first active failure mechanism is compared with that actually active during the 20–29 May shakes. A preliminary modal analysis is also conducted to evaluate vibration modes, to compare the numerical limit analysis acceleration with the spectral acceleration kept by the structures. [Copyright &y& Elsevier]

To investigate the hydraulic behaviour of the fine-grained embankments along the mid-course of the Po River, research was carried out on a full-scale physical model, built on the floodplain along the existing embankment and forming a pond. The pond was filled to reproduce historical floods. The prototype was built according to recommendations formulated by the Po River Management Authority. The engineering properties of the foundation soils were investigated by in situ tests and complemented by some suction-controlled laboratory tests. Pore-water pressure was measured in the embankment and in its foundation before, during, and after the experimental reproduction of two floods that occurred in 1976 and 2000. Atmospheric variables were monitored at the prototype site. Monitoring data refer to 6 months of experimental activities. Pore-water pressure measurements were first presented and subsequently interpreted through an isothermal two-dimensional flow approach where boundary flow rates express the evolution of atmospheric variables. The distribution of the pore water provided by this interpretation was used for stability analyses of the prototype. Results from the experimental activities and their interpretation indicate that the river embankment remains extensively unsaturated during floods. Typical suction trends within the embankment, suction-associated soil strength, and the resulting slope stability safety factors are also shown. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents experimental and numerical results of the first phase of a multi-phase comprehensive joint research program between University of Salerno, Italy, and the University of California, Irvine, USA, on investigating one of the major structural issues that defines the strength limit-state of pultruded fiber-reinforced polymer (PFRP) profiles. Specifically, the strength and stiffness of the web–flange junction (WFJ) of the majority of commercially-produced pultruded composite profiles. A summary of experimental results for 28 full-scale pull-out tests are presented and typical modes failure are identified. Moreover, the influence of the pull-out load distance (d) from the edge of the specimens on the failure strength of the web–flange junction has been investigated and a new definition for an “influence zone” is proposed that is found to be dependent on the loaded length, with a maximum value equal to approximately the PFRP member’s depth. This proposed zone was observed in all laboratory tests and its existence was confirmed by the results of FEM numerical analysis. 3-D finite-element models were also developed to predict the behavior of these specimens. The results from the numerical models were compared to those obtained from the experimental program and found to be satisfactory. [Copyright &y& Elsevier]

The accurate determination of locations and magnitudes of seismic events in a monitored region is important for many scientific, industrial and military studies and applications; for these purposes a wide variety of seismic networks are deployed throughout the world. It is crucial to know the performance of these networks not only in detecting and locating seismic events of different sizes throughout a specified source region, but also by evaluating their location errors as a function of the magnitude and source location. In this framework, we have developed a method for evaluating network performance in surface and borehole seismic monitoring. For a specified network geometry, station characteristics and a target monitoring volume, the method determines the lowest magnitude of events that the seismic network is able to detect (Mwdetect), and locate (Mwloc) and estimates the expected location and origin time errors for a specified magnitude. Many of the features related to the seismic signal recorded at a single station are considered in this methodology, including characteristics of the seismic source, the instrument response, the ambient noise level, wave propagation in a layered, anelastic medium and uncertainties on waveform measures and the velocity model. We applied this method to two different network typologies: a local earthquake monitoring network, Irpinia Seismic Network (ISNet), installed along the Campania-Lucania Apennine chain in Southern Italy, and a hypothetic borehole network for monitoring microfractures induced during the hydrocarbon extraction process in an oil field. The method we present may be used to aid in enhancing existing networks and/or understanding their capabilities, such as for the ISNet case study, or to optimally design the network geometry in specific target regions, as for the borehole network example. [ABSTRACT FROM AUTHOR]

Abstract: A programme of structural assessment and control is currently in progress at Palazzo Ducale in Venice, to evaluate the state of preservation of the two external Medieval façades. A long-term monitoring system of mono-directional accelerometers was set up to investigate the dynamic out-of-plane behaviour of the south façade along a vertical section. A type of action that could be taken as ordinary, involving frequencies in the range of 60–80Hz, was identified during the first months of activity; the response to this kind of dynamic stress allowed a reliable evaluation of the dissipation properties of the structure. As well, the response to an extraordinary-type event, i.e. an earthquake, could be measured during the monitoring period. The first numeric elaborations based on experimental data are presented, i.e. a first calibration of the model of the south façade, aimed to establish the boundary conditions of the model (i.e. translational stiffness of connections to roof and floor structures), by means of spectral analysis with input experimental response spectrum. The good performance of this preliminary numerical model could finally be assessed. [Copyright &y& Elsevier]

Abstract: Buildings’ thermal-energetic assessment and the relative proposal of new technical solutions applied to both summer and winter analyses has a strategic role in increasing the year-round performance of buildings. Buildings’ dynamic analysis is by now a well-established procedure to study effective building energy performance given real climate considerations. Then in this work, a concise and effective methodology for analyzing buildings’ thermal performance in a dynamic environment is proposed and applied to different case studies, consisting of single-family residential buildings’ prototypes. This procedure is aimed to define different performance levels by proper non-dimensional indexes named thermal deviation indexes (TDI). These indexes values could express in a concise way buildings’ thermal behavior, different optimization strategies impact, sensitivity analysis results. Buildings’ prototypes representing the case studies are three free-floating houses where the architectural shape role and the sensitivity of different envelope features are analyzed, also supported by experimental results regarding envelope properties measured on existing residential buildings in Italy. The three prototypes are respectively designed to optimize summer or winter energy performance or to represent the typical Italian house before and after energy efficiency regulation is implemented. To better define the important envelope parameters necessary to calibrate the numerical models, experimental activities are conducted. In particular, thermal insulation level and roof reflectance, characterized by means of spectrophotometrical measurements, are measured both in the case of an old traditional Italian building and in the case of a modern building. The results of the dynamic analysis are expressed in terms of TDI values, to define buildings’ thermal performance with respect to the variation of all the considered architectural and envelope’s properties (i.e. architectural layout, mass and insulation, roof reflectance, Solar Heat Gain Coefficients of windows’ glasses, weather data) within a specific climatic context. For validating the proposed method, the obtained TDI results are compared with those obtained from existing procedures. In particular, the TDI values are correlated to an adaptive comfort indicator, for verifying how much the TDI could be effective for evaluating free-running buildings thermal performance during both summer and winter. [Copyright &y& Elsevier]

Abstract: Snow stability assessment by interpreting snow profiles is a time consuming and fairly subjective process, especially when snow stratigraphy was recorded without performing a stability test at the same time. Snow stratigraphy is clearly related to snow stability, as had been shown by various studies that linked specific snowpack properties such as grain size and type to instability. We suggest a new method to visualize snow stratigraphy in regard to stability based on six structural variables (also known as the threshold sum approach). Each snow layer is represented by the number of variables that are not in the corresponding critical range. This approach has not only been implemented for manually recorded snow profiles but also – after adapting the threshold values – for simulated snow stratigraphy provided by the numerical snow cover model SNOWPACK. The new visualization method, applied both to the manually observed and simulated profiles, was tested by analyzing the most critical avalanche situations of the winter 2008–2009 in the Dolomites (north-eastern Italian Alps). Results indicate that the new visualization method is well suited to quickly and intuitively derive snow stability, in particular from simulated snow stratigraphy. Stability information derived from simulated profiles was clearly related to the independently estimated degree of avalanche danger. Supplementing the snow cover model SNOWPACK with the adjusted threshold sum approach increases its usefulness for avalanche forecasting purposes. [Copyright &y& Elsevier]

Abstract: The Ligurian Alps (Italy) straddle a complex and ill-defined tectonic transition that accommodates Eurasia–Adria shortening driving concurrent growth of the western Alps and northern Apennines. We focus on the Plio-Quaternary landscape evolution of the eastern part of the Ligurian Alps with the goal of defining the active tectonics through an analysis of topography, drainage networks, and river long profiles. The Ligurian Alps have a steep, seaward-facing escarpment with topographic features reminiscent of the geomorphic markers preserved on both actively-uplifting coastlines and passive margins. For example, there are seaward-facing benches that are thought to be uplifted marine terraces common to active margins; but the drainage divide of the seaward escarpment shows clear evidence of recent northward migration into the Po foreland, a process consistent with escarpment retreat characteristic of passive or subsiding margins. This study explores the active tectonics consistent with these diverse landscape evolution pathways. Our analysis reveals that rock-type strongly throttles the development of topographic relief, drainage networks, and northward migration of the drainage divide. However, we also identify segments of the escarpment that indicate recent base level falls through an analysis of modeled channel steepness and comparison with mean hillslope gradient. The base level falls are consistent with numerous barbed tributaries that are best explained as recent stream captures. No significant correlation among the stream captures at the drainage divide, suspected marine terraces at the coast, Ligurian Sea bathymetry, and active seismicity indicates that the escarpment is the footwall of a segmented normal fault. This normal fault is embedded in a regionally subsiding margin where actively uplifting segments lead to a straightened, pinned drainage divide, whereas, relatively inactive segments permit divide migration into the footwall block. These results are broadly consistent with rock uplift increasing eastward toward Genova across the long-suspected Alps–Apennine Sestri–Voltaggio fault zone. They highlight the respective roles of legacy structures, rock-type, and localized rock uplift in constructing a landscape in an otherwise extending and subsiding crustal retrowedge of an active subduction plate boundary. [Copyright &y& Elsevier]

This article shows how local knowledge may be valuably integrated into a scientific approach in the study of large and complex hydrological systems where data collection at high resolution is a challenge. This claim is supported through a study of the hydrodynamics of a large lake where qualitative data collected from professional fishers was combined with theory to develop a hypothesis that was then verified by numerical modeling. First the fishermen's narratives were found to describe with accuracy internal wave motions that were evident in water column temperature records, which revealed their practical knowledge of the lake's hydrodynamics. Second. local knowledge accounts emphasized the recurrent formation of mesoscale gyres and return flows in certain zones of the lake in stratified conditions, which did not appear in the physical data because of limitations of sampling resolution. We hypothesized that these features developed predominantly because of the interaction of wind-driven internal motions with the lake's bathymetry and the Earth's rotation in the widest areas of the basin. Numerical simulation results corroborated the fishers' descriptions of the flow paths and supported the hypothesis about their formation. We conclude that the collaboration between scientific and local knowledge groups, although an unusual approach for a physical discipline of the geosciences, is worth exploring in the pursuit of a more comprehensive understanding of complex geophysical systems such as large lakes. [ABSTRACT FROM AUTHOR]

Abstract: The Moscardo Torrent basin (Eastern Italian Alps) is a high-risk site, since a large roto-translational landslide might dam the torrent, with the consequence of increasing the possibility of large debris flow events, creating a threat for the infrastructures and the socio-economic activities of the villages that dot the valley below. The landslide, whose volume is estimated 2millionm3, has been monitored since 2006 with inclinometers, electric piezometers and a GPS network. The velocity, along the entire body of the landslide, averages 1.0–1.5cm per month. The shear surface develops at depths varying from 9 to 10m to 55–62m, while the groundwater table is almost constant throughout the year, despite a cumulative rainfall of the area that usually reaches 2000mm/year. The movements were simulated in a numerical model, in order to estimate the stabilization effect obtained by different types of possible countermeasures. The simulation was carried out using FLAC 2D, with creep modelling. Visco-elasto-plastic model of the medium in the sliding zone was assumed, allowing to determine the relation between time and displacement. A 10-year displacement trend, starting from the initial situation of 2006 was simulated. Moreover, seismic conditions were taken into consideration with a quasi-static approach, by applying a horizontal acceleration. The numerical model was built and validated on the basis of the data retrieved from geological investigations, as well as from inclinometric and GPS measurements. The results show that an accurate and well-planned multidisciplinary approach can help the decision makers in the choice of the most effective engineering solution for the mitigation of landslide hazard and risk. [Copyright &y& Elsevier]

Abstract: The paper deals with the dynamic characterization and the evaluation of the seismic performances of historical masonry towers and bell-towers that are particularly vulnerable with respect to seismic actions. The main purpose of the study is to investigate how the seismic assessment of such historical constructions is influenced by the level of refinement of the adopted models and by the type of the performed analyses. The effectiveness of some provisions contained in the Italian guidelines for the seismic risk assessment and mitigation of cultural heritage for this kind of structures is also evaluated. The study is performed with reference to the medieval civic tower of Soncino (Cremona, Italy), that is representative of the considered class of masonry constructions. The dynamic characteristics and the mechanical properties of the masonry tower are evaluated through a dynamic identification with ambient vibration tests. Analytical models of the tower characterized by different refinement levels are calibrated on the results of the performed dynamic identification and used to carry out nonlinear static and dynamic analyses. The performed analyses evidence the very conventional nature of the behaviour factor q for this kind of structure. Moreover from the analyses it results that the q values suggested by the Italian codes overestimate the actual q values. The results obtained with the nonlinear dynamic analysis are in a good agreement with those obtained with the nonlinear static analysis. However the nonlinear dynamic analysis provides levels of displacement capacity lower than those resulting from the nonlinear static analysis and allows to consider the significant effect of the higher frequencies on some of the response parameters, as the base shear. The vulnerability of the tower is also assessed according to the Italian guidelines for the seismic risk assessment and mitigation of cultural heritage using the results of the performed nonlinear static analysis. [Copyright &y& Elsevier]

This paper presents the structural health assessment of a railway ancient masonry arch bridge located in Bologna, Italy. A three-dimensional finite element model of the entire bridge, tuned on in situ experimental tests, has been used for the assessment. In particular, the finite element model has been employed to evaluate the structural health of the bridge both in its actual state and in the hypothesis of a structural strengthening intervention. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study on a deep-seated gravitational slope deformation affecting the eastern slope of the Mt. Rocchetta ridge (central Apennines, Italy). Fieldwork identified the ongoing deformational process and assisted in defining its mechanisms, evolution and controlling factors. An equivalent continuum approach was adopted to characterize the rock mass with some modification for the temporal and spatial scale of the process. A visco-elastic-plastic rheological model was adopted for the numerical analysis, which also took into account the groundwater flow feeding the Capo Volturno spring. The results of the numerical analysis are consistent with the observed geomorphic evidence and suggest a morpho-evolutionary model of the ridge characterized by an initial phase of rock mass creep followed by a rock mass spreading process, mainly controlled by the viscous behaviour but with a significant contribution from groundwater for the smaller scale instabilities. [ABSTRACT FROM AUTHOR]

Abstract: Current approaches to rocky slope stability analysis require knowledge of the geometrical–structural setting, as well as the physical–mechanical properties of the intact material and its discontinuities. The physical–mechanical properties are derived from in situ and laboratory tests, whereas the geometrical characteristics come from field attitude measurements. Frequently, the inaccessibility of walls does not allow direct measurement of discontinuity surfaces by traditional geological methods. In such cases, data can only be obtained by statistical methods. Although this approach is significant and provides spatial meaning, it is ineffective for deterministic analysis. This paper provides a solution to this problem by applying digital terrestrial photogrammetric techniques employing a reamed bar, an aerostatic balloon and a helicopter. Results demonstrate that the accuracy and the quantity of geometrical and engineering–geological data coming from the photogrammetric survey, allow for numerical simulation of the relationship between rock elements as a function of their physical–mechanical properties and load conditions. The 3DEC code was chosen among the different methods available to model the discontinuous media through distinct elements. The proposed methodology was applied to a quarry located in the Carrara Marble District (the Apuan Alps, Italy), the largest and most exploited mining region in Europe. The economic value of the area required a detailed study of the presence of instability phenomena so that marble extraction could continue in safe conditions. [Copyright &y& Elsevier]

Abstract: An unusually intense subsynoptic-scale cyclone has been documented in southeastern Italy on 26 September 2006. Numerical simulations are performed with the Weather Research and Forecasting model (WRF). Model results show that the model is able to realistically capture the timing and intensity of the cyclone, identifying in this small-scale cyclone the typical characteristics of a Mediterranean tropical-like cyclone. Sensitivity experiments to sea surface temperature (SST) of the simulated cyclone are discussed in the present paper. In these experiments the SST was changed by a constant few degrees uniformly throughout the Mediterranean Sea. The simulated-cyclone sensitivity to SST is studied in the framework of an air–sea interaction theory, in particular during the two phases that are fundamental for the development of an environment favorable to severe convection and thus for the cyclone to be self-sustained. The modifications of the properties of the simulated cyclones are then analyzed using an objective evaluation, based on a phase diagram used to study the tropical–extratropical transition of cyclones. The present simulations show that the features typical of a tropical cyclone are progressively lost as the SST is reduced. In the colder SST experiments, the lower intensity of the sea-surface fluxes has the effect of delaying and reducing the development of convection and the intensification of the cyclone, so that the cyclone loses the characteristics of a tropical cyclone when SST is reduced by more than 4°C. On the other hand, the cyclone shows a pressure minimum deeper than the control run, with a persistent symmetric warm core, for SST increased by more than 2°C. Finally, when SST is changed by less than 2°C, the cyclone depth and trajectory are not significantly affected by the change in SST and, like the control run, show tropical-like features only for a limited period. [Copyright &y& Elsevier]

Abstract: In this paper the thermal behaviour of a rainscreen ventilated façade has been investigated both experimentally and numerically. Field measurements were performed during the 2009/10 winter season in a test building located in San Mauro Pascoli (Italy) having a squared base of internal dimension of 2.89m and a total internal height of 7.75m. The external walls of this tower are rainscreen ventilated façades with a 24cm air cavity and an external side composed of stoneware with open joints. Ventilation grills are located at the top and at the bottom of the tower. In this work the modelling of the test building using a dynamic thermal simulation program (ESP-r) is presented and the main results discussed. In order to study the rainscreen ventilated façade three different multi-zone models were defined and the comparison with the experimental results has been used in order to select the best ESP-r air flow network for the modelling of this kind of envelope component. The thermal analysis of this envelope component evidenced that the ventilated façade is able to reverse the direction of the heat flux through the envelope in regions characterized by large solar irradiation during the winter and moderate wind velocity, when the indoor–outdoor air temperature difference is small, thereby reducing the energy consumption required for indoor heating. [Copyright &y& Elsevier]

The article presents a research study that deals with the accuracy of the surface high-resolution temperature forecast for the Calabria region, Italy. Researchers have exerted their efforts in quantifying the forecast errors that have been gathered through cumulative statistical method. They used Optimal Interpolation's gridded analysis to determine the region's maximum and minimum temperature.

Abstract: Aim of this paper is to develop simple tools for mapping — at regional and local scale — coastal areas exposed at flooding risk. A two-step simplified procedure for coastal management purposes is presented and is applied to Emilia Romagna (Italy), whose low and sandy coast faces the relatively mild Northern Adriatic Sea. The procedure is composed by a 1D conceptual model to determine flooding probability along wide coastal stretches and by a more detailed 2D Level II reliability method, that provides local quantitative statistical maps of inland flooding propagation. Qualitative maps obtained by literature approaches and quantitative results of flooding probability along the littoral show a good agreement. A coastal flood state indicator is proposed to rapidly assess coastal hazard. [ABSTRACT FROM AUTHOR]

The Nora alluvial fan, which is located in the Orco River valley (Piedmont region, Italy), was affected by a debris flow of approximately 10 000 m3 in October 2000. The event was triggered by heavy rainfall that affected the whole Piedmont region at that time. The mobilization of the water-satured altered gneissic bedrock and colluvium in the upper zone of the Nora basin resulted in the detachment of a debris slide, which rapidly evolved into a channelized noncohesive debris flow. As information from post-event surveys and two pre-event digital elevation models (DEMs), with different resolutions, were available for the study site, the dynamics of the event has been numerically back-analyzed using the numerical code RASH3D. The obtained results have shown both the capability of the code to simulate the dynamics of a noncohesive debris flow, including the final deposit depth distribution, and the importance of on-site surveys and digital elevation model (DEM) resolution in interpreting numerical results and the associated calibrated rheological parameters. [ABSTRACT FROM AUTHOR]

The article offers information on the study which explores the seasonal characteristics of the breeze circulation at a coastal Mediterranean site in South Italy. The study revealed that breezes has played a major role for the coastal's local climate and has dominated the local circulation. It further discusses the recommendations for the research study.

In this paper, we propose quasi-optimal error estimates, in various norms, for the streamline-upwind Petrov-Galerkin (SUPG) method applied to the linear one-dimensional advection- diffusion problem. We follow the classical argument due to Babuŝka and Brezzi; therefore, the goal of this work is the proof of the inf-sup and of the continuity conditions for the bilinear stabilized variational form, with respect to suitable norms. These norms are suggested by our previous work [G. Sangalli, Technical report 1221, 1AN-CNR, Pavia, Italy, 2001; Numer. Math., to appear], in which we analyze the continuous multidimensional advection-diffusion operator. We obtain these results by means of function space interpolation. [ABSTRACT FROM AUTHOR]

This study is motivated by the amplified transmission rates of the SAR-CoV-2 virus in areas with high concentrations of fine particulates (PM 2.5) as reported in northern Italy and Mexico. To develop a deeper understanding of the contribution of PM 2.5 in the propagation of the SAR-CoV-2 virus in the population, the deposition patterns and efficiencies (DEs) of PM 2.5 laced with the virus in healthy and asthmatic airways are studied. Physiologically correct 3-D models for generations 10–12 of the human airways are applied to carry out a numerical analysis of two-phase flow for full breathing cycles. Two concentrations of PM 2.5 are applied for the simulation, i.e., 30 μg⋅m−3 and 80 μg⋅m−3 for three breathing statuses, i.e., rest, light exercise, and moderate activity. All the PM 2.5 injected into the control volume is assumed to be 100% contaminated with the SAR-CoV-2 virus. Skewed air-flow phenomena at the bifurcations are proportional to the Reynolds number at the inlet, and their intensity in the asthmatic airway exceeded that of the healthy one. Upon exhalation, two peak air-flow vectors from daughter branches combine to form one big vector in the parent generation. Asthmatic airway models has higher deposition efficiencies (DEs) for contaminated PM 2.5 as compared to the healthy one. Higher DEs arise in the asthmatic airway model due to complex secondary flows which increase the impaction of contaminated PM 2.5 on airways' walls. [Display omitted] • Deposition of PM 2.5 laced with the virus in healthy and asthmatic airways was studied. • 3-D models for generations 10–12 of the human airways were applied. • Two concentrations of PM 2.5 of 30 and 80 μg⋅m−3 were applied for the simulation. • Asthmatic airways had higher deposition for contaminated PM 2.5 than healthy ones. • Higher DEs in asthmatic airways were due to complex secondary flows. [ABSTRACT FROM AUTHOR]

The present research paper properly focuses on the dynamics and failure mechanisms of the masonry "Apennine Church" of Santissimo Crocifisso in Pretare, municipality of Arquata del Tronto in the province of Ascoli Piceno (Marche region, Central Italy). Such a peculiar structural type traditionally characterizes the intense seismic area of Central Italy, unfortunately almost totally damaged by the recent shock sequence of 2016. Advanced numerical modeling through discontinuous and continuous approaches were here utilized to have an insight into the dynamic properties and behavior of the structure under strong nonlinear dynamic excitations. In the discrete element approach, the non-smooth contact dynamics method, implemented in LMGC90©, was applied, adopting a full 3D detailed discretization. The church was schematized as an arrangement of rigid blocks, subjected to sliding by friction and perfect plastic collisions, with a null restitution coefficient. In the finite element approach, the concrete damaged plasticity model available in Midas FEA NX© was involved. This model allows reproducing the tensile cracking, the compressive crushing, and the degradation of the material under cyclic loads. Finally, the numerical analyses provided a valuable picture of the actual behavior of the church, thus giving useful hints for future strengthening interventions. [ABSTRACT FROM AUTHOR]

• Aging problem for a wall package with vacuum insulation panels is studied. • Measures of heat flux and temperatures for 5 years are compared. • Experimental and analytical elaborations are combined for finding the aging trend. • The aging curve is implemented in a case study by means of dynamic simulation tool. • Energy consumptions, environmental indices and cost savings are discussed. The lack of data on the aging rate, under real operating conditions, is one of the most critical aspects for the diffusion of vacuum insulation panels in the building sector. This problem is analyzed in this paper by means of an integrated experimental-numerical approach. The panels under investigation are characterized by micro-porous silica pressed powder core with an aluminum barrier layer, for a total thickness of 10 mm. These are the insulation layer of a wall made of autoclaved aerated concrete blocks (total thickness of 21 cm) placed in a test room located in Benevento (south Italy). The experimental analysis is focused on the monitoring of heat flux and temperatures in order to evaluate the performance by means of the comparison with the same wall without insulation and for the indirect determination of the aging after five years (2015–2020). Results indicate an increment of thermal conductivity of 10.6%. Moreover, basing on experimental data, a semi-empirical linear function is appropriate to approximate the aging trend. A numerical case study, that implement the obtained aging trend, shows that the increment of thermal conductivity of vacuum insulation panels brings a reduction of the expected energy saving of 3% after 15 years. This result is true for several European cities with heating dominated climates. [ABSTRACT FROM AUTHOR]

In this study, the sustainability of low-temperature geothermal field exploitation in a carbonate reservoir near Mondragone (CE), Southern Italy, is analyzed. The Mondragone geothermal field has been extensively studied through the research project VIGOR (Valutazione del potenzIale Geotermico delle RegiOni della convergenza). From seismic, geo-electric, hydro-chemical and groundwater data, obtained through the experimental campaigns carried out, physiochemical features of the aquifers and characteristics of the reservoir have been determined. Within this project, a well-doublet open-loop district heating plant has been designed to feed two public schools in Mondragone town. The sustainability of this geothermal application is analyzed in this study. A new exploration well (about 300 m deep) is considered to obtain further stratigraphic and structural information about the reservoir. Using the derived hydrogeological model of the area, a numerical analysis of geothermal exploitation was carried out to assess the thermal perturbation of the reservoir and the sustainability of its exploitation. The effect of extraction and reinjection of fluids on the reservoir was evaluated for 60 years of the plant activity. The results are fundamental to develop a sustainable geothermal heat plant and represent a real case study for the exploitation of similar carbonate reservoir geothermal resources. [ABSTRACT FROM AUTHOR]

• A tool to detect spatio-temporal landslide-induced effects on buildings is presented. • Building performace is investigated by DInSAR and structural analyses. • Pre- and post-repair intervention is analyzed by DInSAR time-series. Slow-moving landslides are a natural hazard which affects wide areas in the world and often are cause of significant damage to structures and infrastructures. Analysis of landslide evolution and of their interaction with existing man-made structures plays a key role in risk prevention and mitigation activities. To this purpose, a considerable interest towards innovative approaches has grown among the scientific community and land management institutions. In this work, Synthetic Aperture Radar data acquired by C-band and X-band sensors, combined with numerical analyses, have been successfully applied as a tool to detect spatial and temporal landslide-induced effects, in terms of deformations and structural behavior of a building affected by ground instability. Such approach has been applied to Moio della Civitella urban settlement (Salerno province, Italy), whose whole territory is interested by several slow-moving landslides. In detail, performance of a masonry building aggregate and the efficacy of restoration works have been investigated through an integrated assessment of displacement time-series pre- and post-repair intervention, and structural analysis performed with numerical code. Historical DInSAR data have permitted firstly the interpretation of building displacement time-series corresponding to pre- and post-works configurations; subsequently, the analysis of interpolated interferometric products has allowed to define gradient maps of vertical and horizontal displacements and to identify part of aggregate which can suffer a greater susceptibility to damage as a consequence of deformation gradients. Finally, the comparison of satellite and numerical data showed a substantial agreement with local failures and damage surveyed, thus confirming the capability of DInSAR technique to investigate building performance where no in situ displacement measurements were available. [ABSTRACT FROM AUTHOR]

During recent years, the availability of innovative monitoring instrumentation has been a fundamental component in the development of efficient and reliable early warning systems (EWS). In fact, the potential to achieve high sampling frequencies, together with automatic data transmission and elaboration are key features for a near-real time approach. This paper presents a case study located in Central Italy, where the realization of an important state route required a series of preliminary surveys. The monitoring system installed on site included manual inclinometers, automatic modular underground monitoring system (MUMS) inclinometers, piezometers, and geognostic surveys. In particular, data recorded by innovative instrumentation allowed for the detection of major slope displacements that ultimately led to the landslide collapse. The implementation of advanced tools, featuring remote and automatic procedures for data sampling and elaboration, played a key role in the critical event identification and prediction. In fact, thanks to displacement data recorded by the MUMS inclinometer, it was possible to forecast the slope failure that was later confirmed during the following site inspection. Additionally, a numerical analysis was performed to better understand the mechanical behavior of the slope, back-analyze the monitored event, and to assess the stability conditions of the area of interest. [ABSTRACT FROM AUTHOR]

Renewable energy sources, especially wind power, have become a focus of energy policies in several countries around the world. Wind turbines have to be located on sites with high wind speeds, this leads to high forces acting upon the tower and the blades, causing vibrations throughout the structure. Current technical and scientific literature specifically focusses on vibrations of the wind turbine blades and the effect of earthquakes on the turbines. Additionally, there is considerable research in the field of low frequency noise and infrasound from wind turbines. This study presents the preliminary results retrieved from the analyses performed on real accelerometric time-histories recorded on a cracking wind-turbine located in southern Italy. The permanent accelerometric monitoring system has been installed in 2016, and it is recording data every day under several climatic conditions. Particularly, both weak- and strong-motion synchronized data are available from two three-directional stations: the first one, installed on the foundation and, the second one, installed on the top of the tower. In this phase of the study the recorded motion of the monitored tower has been investigated under several wind conditions correlating the dynamic characteristics of the structural eigenfrequencies with others parameters such as wind speed, air temperature, etc. Accelerometric data have been analysed using both stationary and non-stationary tools, particularly, weak-motion data have been analysed using Fourier Transform and Transfer Functions, while, strong-motion data have been analysed using the Stockwell Transform. In order to analyse the cracking phenomena observed at the base of the tower, also numerical analyses are in progress with the aim to evaluate stresses and strains associated to the complex thermo-mechanical behaviour of materials constituting the monitored tower and any fatigue phenomena. [ABSTRACT FROM AUTHOR]

The article discusses the familiar geometrical demonstrations of French and Italian engineers in the 16th century. It notes that military engineers did not have the societal standing of mathematicians though they need solid theoretical knowledge and practical experience. It suggests that engineers can lift their status and increase their power over the common soldier by preventing the understanding of Euclid on mathematics. It points out that the 16th century societal pressure to abstract significant mathematics contrasts the modern-day mathematicians' translation of math into everyday language.