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• A methodology to set credible speed limits is provided. • The methodology considers the roadway design characteristics and the drivers' operating speeds. • Speed prediction models and driving simulator experiments have been integrated and compared. • The methodology has been tested on the A16 Naples–Canosa motorway, section Baiano–Candela, in southern Italy. • The proposed safety countermeasures have a benefit/cost ratio of 4.66. Speed management is an integral part of the Safe System approach and tackling unsafe speeds is the first action to fix a transport system that fails to protect people. There is a consensus that where traffic speeds are a safety issue, lowering the speed limit is considered "reasonable and safe" for conditions. Nevertheless, not only should a speed limit be reasonable and safe, but it should also be credible. Otherwise, that posted speed limit is likely to be ignored. In many instances, speed limits are not credible and highway agencies still need guidance on appropriate procedures to set credible speed limits. The main objective of this study is to propose and test a novel methodology to set credible speed limits, based on the integration of the results achieved by numerical analyses and driving simulator experiments. The proposed methodology is innovative since it takes into consideration both the design characteristics of the road infrastructure according to a specific procedure as well as the drivers' operating speeds, which are evaluated using the results of both speed prediction models and driving simulator experiments. The methodology was tested to set new speed limits on the A16 Naples–Canosa motorway, section Baiano–Candela, in southern Italy, where a posted speed limit of 80 km/h is installed in both travel directions and a new speed limit of 100 km/h is proposed, based on the results of the experiments developed within the methodology. Since the speed limit selection is associated with the expected crash frequency, the final selection of the speed limit should take into account also a safety impact assessment, considering both the expected change in the speed distribution as well as the effects of the safety countermeasures implemented in association to the speed limit change. In this study, the proposed safety countermeasures are the activation of four sections with point-to-point speed control and targeted measures at 45 curves, consisting of (1) high friction surface treatments, (2) correction of superelevation deficiencies, (3) installation of curve warning signs, chevrons, and sequential flashing beacons, and (4) shoulder rumble strips. The safety impact assessment shows that the increase in the speed limit combined with the implementation of the proposed safety countermeasures allows a crash reduction of 23%. The estimated benefit/cost ratio of the safety countermeasures is 4.66. [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]

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]

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]

A hybrid seismic fragility model for territorial-scale seismic vulnerability assessment of masonry buildings is developed and presented in this paper. The method combines expert-judgment and mechanical approaches to derive typological fragility curves for Italian residential masonry building stock. The first classifies Italian masonry buildings in five different typological classes as function of age of construction, structural typology, and seismic behaviour and damaging of buildings observed following the most severe earthquakes occurred in Italy. The second, based on numerical analyses results conducted on building prototypes, provides all the parameters necessary for developing fragility functions. Peak-Ground Acceleration (PGA) at Ultimate Limit State attainable by each building's class has been chosen as an Intensity Measure to represent fragility curves: three types of curve have been developed, each referred to mean, maximum and minimum value of PGAs defined for each building class. To represent the expected damage scenario for increasing earthquake intensities, a correlation between PGAs and Mercalli-Cancani-Sieber macroseismic intensity scale has been used and the corresponding fragility curves developed. Results show that the proposed building's classes are representative of the Italian masonry building stock and that fragility curves are effective for predicting both seismic vulnerability and expected damage scenarios for seismic-prone areas. Finally, the fragility curves have been compared with empirical curves obtained through a macroseismic approach on Italian masonry buildings available in literature, underlining the differences between the methods. [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 Seismic Microzonation of level 3 (SM3) is nowadays a world-wide accepted tool for the mitigation of seismic risk. The SM3 is a complex process involving different disciplines ranging from Geology and Applied Seismology to Structural and Geotechnical Engineering. The outcome of a SM3 is presented on a zoning map in terms of a selected ground shaking intensity parameter and susceptibility to main ground instability (soil liquefaction, settlements, landslides, fault ruptures). In an advanced SM3 study for a given area, four main interdisciplinary steps can be recognized: (1) definition of the reference input motions, (2) construction of the subsoil model, (3) performing of numerical analyses and computing of amplification factors, (4) identification of zones with different geotechnical hazard potential and drawing up of the SM3 map. After the 2016–2017 Central Italy seismic sequence, intensive studies have been performed to obtain SM3 maps in 137 municipalities most damaged by the earthquakes. The aim of these studies has been to obtain a clear background on site effects to perform a correct reconstruction of the municipalities. In the paper, main results and critical issues of the above-mentioned steps of SM3 procedure are discussed together with some remarks on the use of SM3 output in supporting seismic design for reconstruction. [ABSTRACT FROM AUTHOR]

The paper presents the results of 5 case studies on complex site effects selected within the project for the level 3 seismic microzonation of several municipalities of Central Italy damaged by the 2016 seismic sequence. The case studies are characterized by different geological and morphological configurations: Monte San Martino is located along a hill slope, Montedinove and Arquata del Tronto villages are located at ridge top whereas Capitignano and Norcia lie in correspondence of sediment-filled valleys. Peculiarities of the sites are constituted by the presence of weathered/jointed rock mass, fault zone, shear wave velocity inversion, complex surface and buried morphologies. These factors make the definition of the subsoil model and the evaluation of the local response particularly complex and difficult to ascertain. For each site, after the discussion of the subsoil model, the results of site response numerical analyses are presented in terms of amplification factors and acceleration response spectra in selected points. The physical phenomena governing the site response have also been investigated at each site by comparing 1D and 2D numerical analyses. Implications are deduced for seismic microzonation studies in similar geological and morphological conditions. [ABSTRACT FROM AUTHOR]

This paper describes the results of a 2D and 3D numerical modeling carried out on an unstable natural rock slope (volume = 110,000–335,000 m3) located in north-eastern Italy (Friuli Venezia Giulia Region). It was aimed at investigating the mechanical behavior and internal rock mass damage of the unstable slope before the collapse. The numerical simulations testify that the stability condition of the slope is close to the limit equilibrium (strength reduction factor, SRF = 1.03–1.13), as demonstrated by the considerable rock mass damage observed on the field. The overall mechanical behavior of the slope is mainly governed by the kinematic conditions of the secondary internal blocks, which, in turn, depend on the geometry and mechanical properties of the major discontinuities that delimit the adjacent blocks. Slope failure is achieved through internal rock mass damage represented by internal shear and tensile ruptures localized in correspondence with over-stressed zones. The failure mechanism is characterized by sliding along pre-existing discontinuities and inner damage in the form of the enucleation of shear bands that originate internal secondary failure surfaces and/or damaged rock mass zones. The stress–strain modeling predicts intense slope deformations in zones where rock mass damage actually occurred. This paper emphasizes the decisive connection between the geomechanical field survey and numerical modeling. The comparison of surface geological data acquired on the field with the mechanical indicators obtained from the numerical analyses can significantly improve knowledge of the rock mass damage process that involves unstable slopes approaching failure condition. [ABSTRACT FROM AUTHOR]

This paper presents the results of numerical analyses of ground motion in the Red Zone sector of Amatrice hill, violently struck by the 2016–2017 Central Italy seismic sequence. The methodologies used in processing the data to define the numerical model are firstly described. The results obtained from the computational analyses are then presented and discussed by comparing them with experimental data set of weak motion recordings. Computational analyses were performed via both a 2D-numerical FEM model and a pseudo-three-dimensional hybrid model (SiSeRHMap) which develops multispectral maps taking into account topographic effects. Starting from available geological data and geophysical measurements, an original and specific subsoil GIS model was developed and utilised to perform the computational analyses. The preliminary map for fundamental periods computed from the subsoil model is in good agreement with the experimental data. A restricted set of weak ground motions acquired from an accelerometric station located in a reference site was used as input for the numerical analyses, while the signals of the corresponding events recorded at the top of the hill were used as targets in the reliability evaluation analysis of the outputs. In the area of Amatrice hill, which is characterized by a complex geological and topographical context, the reliability analysis shows a good performance of the hybrid model compared to the 2D-FEM model in the prediction of seismic response. Agreement generally was also good with regards to the experimental and computational results, both in relation to the amplitude and to the shape of the spectral amplification that change depending on the hill sector. Considering the predictive reliability of the models, a high amplification, due to topographic effects, was observed for the Red Zone by performing a back-simulation of the 24th August 2016 main shock. The analysis results highlight also that the maximum amplification factors, based on the definition of the Housner intensity, occur in the interval of periods 0–0.5 s covering the fundamental period range of the buildings in this area. [ABSTRACT FROM AUTHOR]

This work is aimed at the numerical interpretation of the evolution of damage and collapses observed on the Civic Tower of Amatrice, caused by the main events of the seismic sequence of 2016 in the Apennine area of Central Italy. In particular, the study considers the response of the tower with reference to the two main events, occurred on August 24th and October 30th, 2016 respectively. Non-linear dynamic analyses were carried out by developing a finite element model and the behaviour of the tower was investigated with reference to the damage and partial collapses produced by the main events. In dynamic numerical analyses, the accelerograms corresponding to the main seismic events obtained with the study of the site effects were used as seismic input. Moreover, studies have been carried out to understand if and which of the interventions of reinforcement/seismic improvement, realized at the beginning of the years '80, have been determinant to limit the damage, avoiding the complete collapse of the tower. The results of the study, on the one hand, allow to highlight a good correspondence between the evolution of the actual damage observed on the tower and the damage assessed by numerical analyses thus demonstrating the validity of the numerical models set up for the analyses. On the other hand, however, they have made it possible to underline how the presence of the improved material and structural reinforcement interventions carried out at the beginning of the years '80 have contributed to avoid the complete collapse of the tower. [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]

Abstract Multiple self-potential (SP) anomalies are analyzed by using a Genetic-Price Algorithm (GPA), which has been recently introduced for the inversion of SP data. The proposed approach is tested on multiple synthetic anomalies, which are modeled by horizontal cylinders. First, a forward modeling is used to analyze the resolution of such anomalies by varying all model parameters. Then, GPA is applied to invert synthetic multiple SP anomalies. The numerical analyses show that the proposed approach is able to fully characterize the anomaly sources by providing the correct values of the model parameters as well as the number of sources, even if Gaussian random noise is added to the synthetic data. Furthermore, to show the computational efficiency of GPA, the results of a comparative analysis with the Very Fast Simulated Annealing algorithm are given. The validity of the GPA approach is confirmed by its application to three examples of self-potential field data from mineral exploration and groundwater investigations, which are presented and discussed in relation to other inversion approaches. Finally, the quantitative interpretation of multiple anomalies along a SP profile crossing the Mt. Somma-Vesuvius volcano caldera (southern Italy) is provided. Highlights • A global optimization algorithm is applied for multiple SP anomaly interpretation. • The effectiveness of the proposed approach is tested on synthetic SP data. • Applications of the algorithm to field anomalies of multiple sources are presented. • The algorithm is shown to be competitive with PSO and VFSA optimization methods. [ABSTRACT FROM AUTHOR]

In this paper, we address the issue of evaluating the seismic site response for sites located on large alluvial plains, for which no reference sites can be identified, but some earthquakes can be simultaneously recorded at both surface and depth. In the proposed method, surface and borehole records are firstly used to assess the local 1D velocity model, then a model representing a virtual reference rock site is defined, and finally the site spectral amplification is calculated through numerical modeling. The effectiveness of the method is demonstrated at the site of Mirandola (Italy). This site is located in an area which suffered heavy damage during the seismic sequence that started in Northern Italy with the Mw = 5.8 event on May 20th, 2012. That time, the site hosted an accelerometer of the National Accelerometric Network, which recorded the whole sequence. A new station, named MIRB (MIRandola Borehole), was installed during 2014; it is equipped with three accelerometric sensors deployed at surface, 31 and 126 m depth, respectively. The results of this study evidence that Mirandola is characterized by an amplification level consistent with that of a class-C soil for up to a period of about 0.45 s, while for higher periods, the amplification lays between class-B and C soils. [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]

Mt. Vesuvius is one of the most studied volcanoes in the world and its proximity to an extremely populated area makes it also one of the most threatening. Violent Strombolian (VS) events have occurred in the most recent history of the volcano, and they are the type most likely to occur in case of reactivation of the volcano in the near future. In order to investigate the dynamics and hazard of this type of eruption, we performed new field and laboratory work and numerical simulations of plume dynamics, fallout and tephra dispersal associated with such eruptions. Attention was specifically focused on the 1906 eruption, a recent and well-studied VS event. Based on new field analyses and historical observations, we reconstructed the temporal evolution of eruption source conditions during the event. The reconstructed explosive phase of the eruption is inferred to have been 8 days long and characterized by two distinct stages: a former short and intense period with sustained convective plume fed by powerful lava fountains (20 h) followed by a prolonged and less intense period of ash emission (172 h). The total grain-size distributions for both phases, used as inputs to the model, were obtained by field work and laboratory analyses. Based on these new volcanological data and reconstruction of wind field direction and intensity, partially derived from historical sources, the 1906 event was numerically simulated and results compared to deposit distributions. The modelling outcomes for the ash emission phase provide a better agreement with the measured tephra mass load for a simulation run in which ash aggregation (described by the models of Cornell et al. J Volcanol Geotherm Res 17:89-109, , and Biass et al. Nat Hazard Earth Syst Sci 14:2265-2287, ) is specifically taken into account, confirming the importance of this process during tephra dispersal. The aggregation model that best fits the simulated results to the measured ground loadings has 80 % of particles Φ ≥ 4 that aggregate uniformly in the range Φ = −1 to 3. Two additional simulations of a VS event were carried out by using meteorological data of two specific periods to exemplify weather's potential on impacts of such eruptions, particularly tephra loading, on the surrounding areas. The model outcomes clearly highlight the major effects of differences in local meteorology on plume dynamics and ash dispersal and the key role of wind shear in determining the cumulative thickness of ground deposits. Results also show that, due to the long duration of this kind of eruption and the large variability in zonal winds at this latitude, ash dispersal and fallout from VS events at Vesuvius represent a probable hazard for all of the territory near Vesuvius, including the city of Naples, where cumulative tephra loadings might reach critical thresholds for roof collapse and infrastructure damage. [ABSTRACT FROM AUTHOR]

Among the several Triassic carbonate platforms of the Dolomites, the high and vertical cliff of the Gusela del Nuvolau Cassian carbonate platform provides one of the best exposures of a platform - basin transition. However, its analysis using traditional filed surveys can often be limited and distorted due to the difficult and often impossible accessibility of its walls and the lack of optimal observation points. For this reason, in this study an analysis based on the Digital Outcrop Model (DOM) developed by Uncrafted Aerial Vehicle (UAV) digital photogrammetry technique was used. The 3D DOM analysis allowed to properly determine the stratal geometry and the fracture network of the carbonate platform and underlying basinal deposits (San Cassiano Formation) and to identify the presence of early deformation structures. These structures were probably driven by the differential compaction of the basinal facies that is due the differential load of the carbonate platform as confirmed by the numerical 2D models. These structures are generally orthogonal to the NE progradation direction of the carbonate platform, as in the nearby Lastoni di Formin platform. • the UAV photogrammetry allows to overcome the limitations of traditional surveys and terrestrial remote sensing techniques. • 3D DOM analysis and 2D numerical models suggest the presence of differential compaction driven early deformation structures. • 3 fracture sets trending NW, NNW and NE affect the Nuvolau platform. Some NW structures are normal synsedimentary faults. • the NE progradation of the platform is approximately orthogonal to the early deformation faults and fractures. [ABSTRACT FROM AUTHOR]

This paper outlines the response of the healthcare system in the area mainly affected by the 2012 Emilia earthquake by drawing on specific surveys and information from local health authorities. Some hospitals were evacuated after the M $$_\mathrm{l}$$ = 5.8 May 20 seismic event due to damage to non structural components and minor structural damage. A short description of the damage suffered and characteristics of the healthcare system as a whole is offered initially, followed by a detailed description of the effects which took place at the Santa Maria Bianca hospital of Mirandola. The focus has been on damage to non structural elements and content, whose integrity is of primary importance for healthcare structures performance during and after a seismic event. Some instruments for the acquisition of accelerometric data were installed after the May 20 event both outside and inside a building which is part of the hospital complex. The seismic behavior of this building has also been analysed by means of a purposely made finite element model and on the basis of the recorded data. The contribution of undamaged and damaged masonry infills to the global seismic response has also been estimated thus providing some hints on the observed building performance. [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]

The earthquake-induced damage to earth-retaining structures located along roadway network clearly affects the operations during the emergency and rescue phases in the immediate aftermath of a seismic event. The prompt estimation of the seismic vulnerability of a structure or a typological class of structures having a similar seismic behaviour is of foremost importance. In this framework, fragility curves represent an effective tool which can be adopted for quickly evaluating the seismic response of strategic structures. Aim of this study is to propose novel sets of fragility functions for earth-retaining structures, which adopt as input the Intensity Measures (IMs) best correlated to the response of the walls. First, target earth-retaining structures identified along the Italian roadway network are numerically modelled and then two-dimensional (2D) dynamic analyses carried out with reference to different geometrical features of the structure (i.e. height and shape of the walls) and configurations of the backfill. Metrics such as efficiency, practicality, proficiency, and sufficiency are assessed for different demand parameters (overall 35 IMs). The structure response is expressed in terms of horizontal displacement and rotation of the wall. Fragility functions for peak values of velocity (PGV) and acceleration (PGA) are developed. The fragility models are then applied for computing the seismic damage scenario associated to a real earthquake occurred in Central Italy in 2016. Predictive capabilities of the models are assessed by comparing surveyed damages. The proposed tools are useful in emergency management and also during preparedness phase to identify the priority actions and proper countermeasures for seismic risk mitigation. • 2D dynamic analyses of earth-retaining walls along the Italian roadway network. • Identification of the optimal intensity measures. • Development of novel fragility curves for earth-retaining walls. • Computation of seismic damage scenario associated to a real earthquake. [ABSTRACT FROM AUTHOR]

Historical sources report that Rome has experienced considerable earthquake ground motion in the past, even though it is quite far from high-magnitude seismogenic sources. Damage distribution seems to be predominantly controlled by ground shaking amplification related to local soil conditions. In this context a multidisciplinary research project has been conducted to determine the seismic microzonation of the Central Archaeological Area of Rome, which includes the Palatine Hill, Roman Forum, and Coliseum. In particular, the present paper details the results of one and bi-dimensional site response analyses carried out within this project, focusing discussion on representative cross-sections. The peculiarity of this work stems from the fact that it represents the first systematic study on the seismic site response of Rome's historical centre based on a robust subsoil model which integrates a large amount of available and original geological, geophysical and geotechnical data. Investigation of the physical phenomena responsible for site effects shows that ground motion distribution is mainly controlled by 1D resonance phenomena and 2D effects associated with soft alluvial valleys bordering the Palatine Hill, a deep paleo-valley and, to a lesser extent, topography and the morphology of anthropogenic deposits. The analyses show maximum amplification factors, defined in terms of Housner Intensity, as high as 1.4-1.8 over the period range of 0.1-1.0 s. Such values can be significantly relevant for the monumental and archaeological heritage of this area, as many are highly vulnerable due to their great age. [ABSTRACT FROM AUTHOR]

In this paper, we focused our attention on a cross-section of the Aterno River Valley where a good quality geological and geophysical dataset allowed to reconstruct accurately the geometry and the Vs profiles along all the plane of the section. Its trace is deliberately aligned close to the strong motion stations that recorded the Mw 6.3 (April 6th 2009) L'Aquila earthquake. We analysed strong and weak motion data available at these latter stations as well as at one of the temporary stations installed during the Microzonation activities and located on outcropping bedrock, in proximity of the cross-section. We used the H/V technique to select a reliable reference site and once we found it, we applied the SSR technique to compute amplification functions in correspondence of two strong motion stations. In turn, for both sites we performed a site response numerical modelling with two different 2D codes and we compared simulated versus experimental transfer functions. We found that the cross-section is well constrained based on the very reasonable agreement between results of numerical modelling and earthquake data analysis. We pointed out also a strong amplification of the deposit at the centre of the valley due to the constructive interference of S and surface waves, not predictable by means of 1D numerical modelling. We also compared the H/V as well as the SSR obtained from strong motion data with the ones computed from weak motion finding evidences of non-linearity in soil behaviour. [ABSTRACT FROM AUTHOR]

Background & Aims: The current organ allocation system for liver transplantation (LT) creates an imbalance between patients with and without hepatocellular carcinoma (HCC). We describe a model designed to re-establish allocation equity among patient groups using transplant benefit as the common endpoint. Methods: We enrolled consecutive adult patients entering the waiting list (WL group, n=2697) and undergoing LT (LT group, n=1702) during the period 2004–2009 in the North Italy Transplant program area. Independent multivariable regressions (WL and LT models) were created for patients without HCC and for those with stage T2 HCC. Monte Carlo simulation was used to create distributions of transplant benefit, and covariates such as Model for End-stage Liver Disease (MELD) and alpha-fetoprotein (AFP) were combined in regression equations. These equations were then calibrated to create an “MELD equivalent” which matches HCC patients to non-HCC patients having the same numerical MELD score. Results: Median 5year transplant benefit was 15.12months (8.75–25.35) for the non-HCC patients, and 28.18months (15.11–36.38) for the T2-HCC patients (p <0.001). Independent predictors of transplant benefit were MELD score (estimate=0.89, p <0.001) among non-HCC patients, and MELD (estimate=1.14, p <0.001) and logAFP (estimate=−0.46, p <0.001) among HCC patients. The equation “HCC-MELD”=1.27∗MELD – 0.51∗logAFP+4.59 calculates a numerical score for HCC patients, whereby their transplant benefit is equal to that of non-HCC patients with the same numerical value for MELD. Conclusions: We describe a method for calibrating HCC and non-HCC patients according to survival benefit, and propose that this method has the potential, if externally validated, to restore equity to the organ allocation system. [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]

• A complete characterization of "Scaglia Rossa" masonry is carried out. • The considered masonry monopolized constructions between 1950 and 60s in Central Italy. • Widespread damages and collapses were observed in the 2016 Central Italy earthquake. • Uniaxial compression, bending and shear-compression tests are performed on stone, mortar and walls. • The first quantitative indications were provided, filling a void in current bibliography. This paper outlines the complete characterization of masonry walls composed of "Scaglia Rossa", a typical stone of the Apennine area between the Umbria and Marche Regions in Central Italy. The study focuses the assessment of the mechanical behavior by means of an experimental campaign carried out in the laboratory of the Polytechnic University of Marche, where the samples of "Scaglia Rossa" masonry, obtained from the controlled demolition of three school buildings, were reconstructed with the same techniques of the 1950s-'60s, and then tested in order to identify both the constituent materials, stone and mortar, and the composite masonry. The experimental tests were prior to a numerical analysis implemented by the adoption of a nonlinear model capturing the cracking behavior. The main mechanical parameters were then calibrated by means of an optimization algorithm of Levenberg-Marquardt, considering a continuous approach with both (i) macro- and (ii) micro-modelling techniques and obtaining resistance parameters not deriving directly from the experimental tests. The comparison between the results obtained from the Levenberg - Marquardt algorithm by changing the parameters of the damage model based on data given by the experimental campaign allowed to confirm the validity of the approach used. [ABSTRACT FROM AUTHOR]

In the present paper a review of some mathematical models for the ecological evaluation of environmental systems is considered. Moreover a new model, capable to furnish more detailed information at the level of landscape units, is proposed. Numerical tests are then performed for a case study in the province of Viterbo (central Italy). [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]

Abstract: Sardinia (Italy) is the second largest island in the Mediterranean Sea and its economy is penalized by high costs of electricity, which is double compared to the continental Italian regions, and triple compared to the EU average. In this research, the wave energy potential of the north-west of Sardinia has been studied by an analysis of wave measurements carried out in a 20-year period by the Italian Wave Buoys Network (1989–2009) and the corresponding hindcast data by the European Centre for Medium-Range Weather Forecasts (ECMWF). The annual offshore wave power was found to range between 8.91 kW/m and 10.29 kW/m, the bulk of which is provided by north-westerly waves. The nearshore energetic patterns have been studied by means of a numerical coastal propagation model (Mike21 NSW). The analyses highlight two “hot spots” where the wave power is respectively 9.95 and 10.91 kW/m. For these locations, a Wave Energy Converter with maximum efficiency in the ranges of significant wave heights between 3.5 and 4.5 m (energy periods 9.5–11 s) and 4–6 m (energy periods 9.5–11.5 s) respectively should be selected. In order to find a concrete solution to the problem of harvesting wave energy in this area, the characterization of waves providing energy is considered along with additional considerations, such as installation and operational costs, institutional factors, environmental sensitivity and interferences with others human activities. On the basis of the information available and the identified circumstances, the site of Bosa Marina has been proposed as a prospective wave farm location. For this site in particular, multifunctional structures like harbour or coastal protection breakwaters equipped with a WEC are recommended. [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]

A phytosociological study of the alliance Carpinion orientalis in the hilly and subcoastal areas of the Italian peninsula is presented. These woods are included in the suballiances Laburno-Ostryenion and Lauro-Quercenion; the distinction between these two suballiances is not always easy also because of the conservation status of these forest ecosystems. The hilly and subcoastal Turkey oak woods of the alliance Carpinion orientalis are mainly distributed on the Adriatic side of the Italian peninsula, where they are found on neutro-basic substrata to which these coenoses are linked. The Turkey oak woods of the alliance Teucrio siculi-Quercion cerridis are strongly linked to the acidic substrata typical of the Tyrrhenian side, but are sporadically found on the Adriatic side within small enclaves with more acidic substrata. A numerical analysis allowed us to rearrange the lower hierarchical levels of the associations of Turkey oak woods of the alliance Carpinion orientalis. In particular, the association Lonicero xylostei-Quercetum cerridis is included in the alliance Carpinion orientalis, and the new subassociation festucetosum exaltatae is proposed. The subassociation rosetosum arvensis is proposed for the association Daphno laureolae-Quercetum cerridis, and the new subassociation cytisophylletosum sessilifolii of the association Aceri obtusati-Quercetum cerridis is described. [ABSTRACT FROM PUBLISHER]

This paper describes the application of the combined finite-discrete element method (FDEM) for the simulation of two different rock slides observed at the Alpetto Mine in Cesana Brianza (Italy). Previous numerical modeling conducted to study the stability conditions of the high rock cut are used as comparison for the results obtained. The paper presents how the FDEM simulation was performed and discusses the ability and limits of the currently available combined method to simulate rock slide problems for practical purposes. [ABSTRACT FROM AUTHOR]

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]

The presence of peats and high compressibility inorganic clays within alluvial fills on the left-side tributaries of the Tiber River, close to Rome's historic center in Italy, is well documented in literature. Nevertheless, few literature data exist until now on the dynamic properties of these deposits by undisturbed bore-hole samples. The Galba test-site was set up to characterise dynamic properties of the alluvial deposits by using lab-tests as well as to derive velocity profiles by seismic noise measurements. These were performed in the Giustiniano Imperatore area located in the Grottaperfetta valley, about 2 km south of Rome's historic centre. The alluvial deposits filled a paleovalley excavated in the bedrock during the Würm glacial (18-20 ky). The stratigraphic setting of the alluvial body was reconstructed along three geological cross-sections by means of the available logs; seven lithotecnical horizons can be distinguished within the alluvial body, some tens of meters thick, based on both log-stratigraphic data and in-site geotechnical tests. These horizons include peaty layers (T) and high compressibility inorganic clays (AGI), which characterise the alluvial deposits in the Grottaperfetta valley. They do not have direct correlation with the alluvial horizons which constitute the alluvial body of the main Tiber valley in Rome's historical centre. These alluvial horizons which are distinguished and characterised at the Galba test-site can be regarded as typical of other lateral valleys of the Tiber River in Southern Rome. They are characterised by the presence of similar high compressibility clayey deposits as well as peaty layers up to some meters thick. Undisturbed samples were also obtained at the Galba test-site for dynamic testing via resonant column and cyclic torsional shear tests. In order to attribute dynamic properties to the alluvial body at the Grottaperfetta valley, an extrapolation process was performed based on a detailed engineering-geology model of the alluvial body which was reconstructed along three transversal geological sections of the valley using bore-hole data. Three subsoil profiles, considered representative of the geological setting along the three reconstructed transversal cross sections, were analysed by seismic noise measurements performed specifically to derive S-waves velocity profiles. The results obtained show a very low velocity (<180 m/s) for the layers T and AGI. 1D modelling of seismic shaking was performed by the code Shake91, in order to evaluate the influence of the low-velocity strata on maximum shear strains induced within the alluvial deposits under the maximum expected seismic action. The results of the numerical modelling indicate that the AGI and the T layers play a key role in: (i) concentrating the maximum shear strain along the subsoil profiles, even though the volumetric threshold is never exceeded; (ii) increasing the maximum shear strain along the subsoil profiles; (iii) causing the resonance frequency of the alluvial fill to assume an almost constant value (about 1Hz) which is quite similar to that measured in the main Tiber River valley, despite a significant change in thickness of the alluvial body along the Grottaperfetta valley. [ABSTRACT FROM AUTHOR]

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]

Abstract: The paper analyses the static behaviour and the seismic vulnerability of the Basilica of Santa Maria all’Impruneta near Florence (Italy). The static structural behaviour and the dynamic properties of the church have been evaluated using the finite element modelling technique, where the nonlinear behaviour of masonry has been taken into account by proper constitutive assumptions. A macro-modelling approach has been used based on the concepts of homogenisated material and smeared cracking and crushing constitutive law. Seismic vulnerability has been evaluated using a pushover method, and the results obtained with the nonlinear numerical model have been compared with the simplified schemes of limit analysis. The capacity of the church to withstand lateral loads is evaluated together with the expected demands resulting from seismic actions. The comparison of seismic demand vs. capacity confirms the susceptibility of this type of buildings to extensive damage and collapse, as frequently observed in similar buildings. The paper’s aim was to point out that advanced numerical analyses can offer significant information on the understanding of the actual structural behaviour of historic buildings. The methodology and the conclusions of this case study it is believed that are applicable to a wide variety of historic Basilica churches. [Copyright &y& Elsevier]

The paper deals with the seismic stability assessment of two existing earth dams in Italy using a fully coupled effective stress nonlinear approach implemented in a finite-element (FE) code. The mechanical behavior of the involved clayey and granular soils is described through advanced elastoplastic constitutive models, calibrated on laboratory and in situ test results. Before the application of the seismic motions, appropriate FE static analyses are performed in both cases to define the initial stress state and the internal variables of the material models. The stability of both dams during dynamic loading is proved by inspection of the cumulated horizontal and vertical displacement time histories of the monitored solid nodes, which become constant immediately after the end of the seismic actions. Moreover, the computed crest settlements induced by the earthquakes are considerably smaller than the service freeboard of the dams. Because the applied seismic actions are characterized by high return periods, the presented results are indicative of a satisfactory dynamic performance of the two embankments during extreme dynamic loading conditions. [ABSTRACT FROM AUTHOR]