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Natural gas is one of the most widely used fossil fuels in the world and it represents an essential element for human activities. It can be stored in underground geological structures such as depleted oil/gas field, aquifers and salt caverns. Underground Gas Storage (UGS) application plays a key role for covering natural gas demand and supply fluctuations, e.g., methane, CH4, by injecting gas in the summer season when the demand is lower, ready to be withdrawn and deployed into the network to meet increased consumer demand in the winter season. Unfortunately, constant human exploitation of fossil fuels causes climate change phenomenon, creating a potential risk of breaching environmental tipping points with negative consequences. In this regard, the carbon capture and storage (CCS) practice, which is different in methods and purpose from UGS, has been gaining popularity in the last decades. The latter strategy involves storing Carbon Dioxide (CO2) before it enters in the atmosphere, by means of geological structures for centuries or thousands of years and it can support one of the most important challenges of the twenty-first century, helping the decrement of the global warming and to chase the goal of near-zero greenhouse gas emissions. Misuse of UGS and CCS activities or poor maintenance of injection and withdrawal wells can induce effects of considerable magnitude such as ground deformation, micro-seismic events, fault reactivation and gas leakage. The development of appropriate injection methods and long-term monitoring systems for leak detection is important to verify the integrity of the reservoir, the effectiveness of activities and the respect of safety conditions. In literature approximately a hundred scientific contribution of UGS and CCS monitoring applications were spanning in the world. All the scientific peer-reviewed books and articles, and congress proceedings about the reservoir monitoring in gas storage activities collected and critically analysed show an analytical and statistical overview of the most common use of UGS and CCS, detailing the different goals of these two applications. This research allows displaying the advantages and drawbacks of each monitoring technique involved in gas storage applications by analysing the main UGS and CCS projects. Further developments are required for the UGS monitoring, especially through multidisciplinary approaches useful for identifying possible effects on the surface and gas leaks at depth; meanwhile, CCS solutions are still at an experimental stage, due to the high costs for large-scale applications that require specific researches. The state of the art of these two very different practices can improve the further development of new monitoring approaches or additional methods. The next years will reveal if the CCS methods will be among the leading techniques in the race for energy transition.

Machine learning algorithms are commonly used for landslide susceptibility mapping; however, their application for spatiotemporal landslides prediction remains widely unexplored. Only static predisposing factors are needed for susceptibility assessment, which indicates where landslides are more likely to occur in the future. Therefore, dynamic parameters, such as critical or antecedent rainfall, which are mainly related to the temporal occurrence of landslides, remain unused.This work provides a contribution to fix this gap by proposing an innovative methodology for the application of the Random Forest (RF) algorithm for spatio-temporal landslides prediction, landing to a more complete hazard assessment. This dynamic approach is based on the method of identification of non-landslide events in comparison with the reporting day and location of the landslide events; conceived to include both static and dynamic parameters as model input variables. Among other advantages, RF allows the calculation of the Out-of-Bag Error (OOBE) and depicts Partial Dependence Plots (PDPs), two useful indices of the influence of each input variable in determining the triggering of landslides. In this work, these indicators were used to verify the applicability of RF with the proposed methodology, investigating if the model outcomes are consistent with the triggering mechanism observed in the inventoried landslides.The study area is the Metropolitan City of Florence (MCF), Central Italy, for which a detailed and dated landslide inventory is available, mainly composed of shallow landslides and debris flows. As first dynamic variable it was chosen to use the cumulative rainfall at various time steps, which allows to consider both short and long-term rainfall. The month of observation of the events is used as second dynamic input parameter, as a categorical type, to represent the seasonal variability. In addition, a static index related to the predisposition of the area to landslides (i.e., a classical susceptibility map) was inserted, to directly compare the influence of static and dynamic parameters on spatiotemporal prediction of landslides.The goals of this research are: i) to understand how to populate training and test datasets with observations sampled over space and time, ii) to assess which rainfall variables are statistically more influential on landslides triggering, and iii) to verify the applicability of the proposed dynamic approach for landslides probability assessment.The RF model employed through the proposed methodology showed encouraging results, consistent with the actual knowledge of the physical mechanism of the triggering of shallow landslides and debris flows (mainly influenced by short and intense rainfall). Some benchmark configurations have been identified which represent a promising starting point for future applications of machine learning models for landslide probability mapping.

Sinkholes that occur in settled carbonate lands can be a critical source of risk for human properties and activities since they can abruptly produce serious damage to property and people in densely populated flat areas. This work presents a sinkhole susceptibility and risk assessment mapping in Guidonia-Bagni di Tivoli plain (Central Italy), which is a carbonate sinkhole-prone study area where sudden occurrences of sinkholes have happened in past and recent times. We consider a point-like sinkhole inventory and a series of environmental sinkhole-controlling factors on the study area, related to its geo-litho-hydrological asset, i.e. travertine thickness, and to its terrain deformational scenario, i.e. ground motion rates derived from InSAR COSMO-SkyMed imagery. A sinkhole susceptibility map was generated by means of maximum entropy algorithm - MaxEnt model – and it was then combined with data on vulnerability and elements-at-risk economic exposure derived from cadastral inventories and market and income values, in order to provide a final sinkhole risk map of the Guidonia-Bagni di Tivoli area. The results show that areas at higher risk covers about 2% of the total study area and primarily relies on the zoning of the main urban fabric. In particular, it is worth to highlight that 5% of the whole road-network pavement and 27% of all the residential buildings fall into higher risk classes. Outcomes of this work reveal the potential of MaxEnt model to assess sinkhole susceptibility for predicting sinkhole areas, either provide a sinkhole risk map as a useful tool for geohazard risk and urban planning management strategies.

Characterization of agricultural soils using geophysical techniques makes it possible to study the heterogeneity of a soil and the preferential pathways of water flows without causing disturbances to soil and plants. Increased knowledge of soil heterogeneity allows the most optimal management of the water resource in terms of crop, yield and sustainability. In this study, time lapse monitoring, using electrical resistivity tomography (ERT), is proposed as a reliable and non-invasive technique to quantify the movement of water flows during the irrigation process.ERT surveys were conducted in melon cultivated land in southern Tuscany (Italy). Four survey campaigns were carried out between June and August 2022, in which ERT data were collected by taking measurements, before, during, and after the irrigation phase. The investigation was conducted with a 3-D grid in which the 72 electrodes were spaced 0.3 m apart and arranged in three parallel lines, 0.3 m apart and 6.9 m long, for a total of 24 electrodes in each line. The plants were located above a ridge having a height of 20 cm with respect to the ground level and the electrodes were positioned to incorporate 5 melon plants in the configuration. A dipole-dipole configuration was adopted for the acquisition of electrical resistivity data. Commercial ViewLab 3D software was used to process the geoelectrical data.The interpretation of the ERT results provided information on the spatial and temporal distribution of water flows in the soil and in the root zone of melons during the irrigation phases. The investigation made it possible to identify the preferential ways of infiltration of the irrigation water, the points where the water is absorbed by the roots, and the points where the water instead follows a preferential way distributing itself entirely below the area of root growth. During the investigations, the irrigation time underwent changes dictated by the climatic conditions, therefore the irrigation time and frequency were increased. This manifested itself in the ERT sections with an increase in the conductivity below the roots, i.e., at a depth of about 35 - 40 cm with respect to the ground level. This phenomenon can be explained by the fact that over time the water has developed a greater preferential path, completely bypassed the root system and collected below it, in the zone delimiting the worked soil with the unworked soil.In the present case study, the ERT technique proved to be a valid survey and monitoring method for mapping the preferential paths of water flows in agricultural land. The ERT sections made it possible to study the distribution of water along the soil profile, highlighting the presence of preferential paths that produce an accumulation of water below the root zone and therefore in an area that is not very usable for cultivation. This technique can therefore be used in this context to study a better irrigation system and an optimal management of the water resource, avoiding preferential paths of the flows which lead to a lower availability of water for the plant.

Back analysis is the most common method to study landslide movements after the event, and it allows us to understand how a landslide evolved along the slope. This paper presents the back-analysis of the Pomarico landslide (Basilicata, Italy) that occurred on January 25th, 2019, on the southwestern slope of the Pomarico hill. The landslide, of rotational clayey retrogressive type—planar sliding, evolved in different phases until it caused a paroxysmal movement in the early afternoon on January 29th, 2019. The landslide caused the collapse of a bulkhead (built at the end of the twentieth century) and of some buildings along the village’s main road. In this paper, a multi-layer back-analysis study is presented, based on the limit equilibrium model (LEM), applying the solution proposed by Morgenstern and Price in Geotechnique 15(1):79–93zh, (1965) and implemented in the freeware software SSAP 2010. The analysis allowed the reconstruction of the entire landslide evolution, using geotechnical parameters obtained from both laboratory and in situ tests, and data from the literature. The application of multilayer back-analysis made it possible to avoid the homogenisation of the layers, modelling the event according to the real conditions present on the slope. The use of the SSAP software made it possible to curb the problem related to the theoretical limitation of the shape of the rupture surfaces, by evaluating independently the friction angle locally and by discarding all those surfaces, which, due to this problem, presented a non-reliable factor of safety (FS) value. The modelling revealed a slope that is highly unstable as the height of the water table changes. The FS calculated under water table conditions close to ground level was less than 1 (FS = 0.98), simulating the first landslide movement (November 2018). The subsequent model reconstructed the critical surface responsible for the January 2019 movement and calculated the FS present on the slope (FS = 1.01). Eventually, the paroxysmal event on January 29th, 2019, was modelled, returning an FS of 0.83, and a sliding surface that sets below the bulkhead, causing its failure. Furthermore, the modelling of the slope in the presence of adequate retaining structures demonstrated the (non-) effectiveness of the retaining wall system represented by the bulkhead. The proposed method of analysis suggests further applications in similar complex multi-layer soil-structure interaction scenarios.

The UNESCO Chair on Prevention and Sustainable Management of Geo-Hydrological Hazards, University of Florence has been a member of the International Consortium on Landslides (ICL) since 2002. It was designated as one of World Centres of Excellence (WCoE) for Landslide Risk Reduction five times for 2008–2011, 2011–2014, 2014–2017, 2017–2020 and 2020–2023, with a project entitled “Advanced Technologies for Landslides”. In this paper, we describe the activities carried out by the UNESCO Chair as a member of ICL and as WCoE, and its contribution to the risk reduction policies promoted by the 2020 Kyoto Commitment.

This paper presents a numerical and analytical study on single-storey cross-laminated timber (CLT) shear-walls with openings subjected to lateral loads. The main objective was to investigate the location and distribution of maximum values of axial and shear forces in relevant wall sections. The influence of parameters such as wall geometry (different sizes of wall openings, door openings, lintel/parapet lengths and heights, wall thickness) and different stiffness levels of mechanical anchors for CLT wall connection with floor/foundation were studied. Finite element (FE) parametric analyses were performed on a set of single-storey CLT shear-walls with door and window openings and were compared with analytical models for determination of internal forces. The importance of wall connections’ flexibility was identified, as the distribution of internal forces in walls with rigid and flexible anchors were considerably different. The obtained outcomes of this study provide a solid base for the next step, an experimental investigation of in-plane internal force distribution in CLT walls with openings, which will serve for further development of numerical, analytical and design approaches.

The issue of salinity in agricultural soils is a growing problem. Soil with a high sodium content in the root growth zone compromises plant health and growth. Irrigation is one of the main techniques used to reclaim high-salt soils, as water dilutes the sodium concentration. In this study, electrical resistivity tomography (ERT) is proposed as a reliable non-invasive technique to quantify sault movement during the irrigation process. The first step was to identify the best set up of electrodes for this type of investigation. 3D-ERT measurements were carried out in two different campaigns to identify the most suitable electrode distribution. The study area is a segment of land, located in Barbaruta (GR, Italy) and used for the cultivation of melons. The investigation site is characterised by irrigated soils in which an accumulation of sodium has occurred over time. To detect the movement of salt during the irrigation phases, ERT surveys were carried out before, during, and after the irrigation phases.Considering the objective of the experiment, the measurement carried out during the first campaign (July 2021) was performed by creating a 3D grid in which the 72 electrodes were spaced 0.2 m apart and arranged in 5 parallel lines, spaced 0.2 m apart, two of which (lines 1 and 5) were 2.8 m long, for a total of 15 electrodes, and three of which (lines 2, 3 and 4) were 2.6 m long, for a total of 14 electrodes. This configuration made it possible to include two melon plants.The survey carried out in the second campaign (August 2021) was carried out with a 3D grid in which the 72 electrodes were spaced 0.3 m apart and arranged in three parallel lines, 0.3 m apart and 6.9 m long, for a total of 24 electrodes in each line. This configuration allowed five melon plants to be incorporated. A Dipole-Dipole configuration was adopted for all the acquisition of electrical resistivity data. The commercial software ViewLab 3D was used to process the geoelectric data.Data analysis showed that the range of conductivity values increases from dry to wet soil conditions, and conductivity increases with depth. The ERTs sections, carried out after the irrigation phase, showed areas where conductivity decreases over time during irrigation, this can be explained by the leaching of salts because of water input. While other areas show higher conductivity after irrigation, and this may mean not only an increase in water content but also a displacement of salts with water input. For this reason, further analysis is required, including the use of Induced Polarisation (IP).The test showed that the best configuration is the one with the electrodes arranged in three lines, as it allows more plants to be incorporated.The test also led to the need to avoid stressing the plants during the measurement phase. This made it necessary to create a special set of electrodes to be installed during the transplanting phase, so as not to disturb the plants during the growth phas.

The “Piano Lauree Scientifiche” is an initiative of the Italian Ministry of University and Education aimed to sustain Science, Technology and Maths studies. It is active since 2005, but only in 2015 Geology courses have been included in the grant system. The “Piano” is structured in seven national disciplinary partnerships, including all the Italian Universities where a BSc course is listed in their undergraduate prospectus. Then, the 29 Universities involved in the Geology Project share general and specific objectives for vocational guidance of incoming students, training of secondary school teachers, and initiatives to reduce the drop-out. The description of these objectives and the results obtained in the last three years are presented and it can stimulate the discussion to improve the project during the next years, when new specific tasks will be added: gender-related issues, enhancement of mentoring and accompaniment initiatives, refresher training for school teachers.

The Tuscany region of Italy is widely affected by subsidence, landslides and floods, which severely impact buildings and infrastructure. In particular, Firenze-Prato-Pistoia basin has a long experience of ground deformation related to groundwater withdrawal. European remote-sensing satellite (ERS) data collected since 1992 have revealed the presence of several subsiding areas in the basin such as the south-eastern portion of the city of Pistoia. Sentinel-1 persistent scatterer interferometry (PSI) measurements for 2015–2018 confirmed the long-term subsidence of this area, associated with intense horticulture (plant nurseries). At the same time, Sentinel-1 data revealed the unexpected movement of Pistoia historic center, which has always been considered stable in the past. To identify the complex relationship between aquifer conditions and ground displacement, a hydrogeologic model of the Pistoia aquifers was developed, applying an integrated modelling procedure. Hydrodynamic-parameter distributions, calibrated and validated by means of Sentinel-1 PSI measurements, suggest that subsidence in Pistoia area is probably related with the combined impacts of groundwater extraction and highly compressible aquitards. To evaluate the potential evolution of ground displacement, numerical simulations were extended until 2050, using regional and global climate model data, analyzing three different pumping-rate scenarios. This led to the development of several subsidence hazard maps of the city of Pistoia that display the influence of groundwater extraction in controlling land subsidence in the area. This study emphasizes the importance of developing proper groundwater management policies, especially in alluvial aquifers made of fine compressible sediments, in order to sustainably utilize underground freshwater resources and to avoid related side effects.

Stromboli island (Italy) provides an outstanding record of volcanic island geomorphological evolution, and of ongoing volcanic phenomena with the example of the “Strombolian” types of eruption. The vegetation of Stromboli includes endemic species, some of which are exclusive to the Aeolian Islands. The western side of the island is characterized by olive trees that were cultivated by exploiting terraces up to high altitudes. All this makes an unique landscape, results of interaction between volcanic activity, geomorphological evolution, and traditional land management. Wildfires at the island of Stromboli are common phenomena related to the fallout of incandescent material on vegetation. Wildfires with small extensions are usually generated by explosions more intense “major” explosions, while large-scale wildfire have been triggered by larger scale activity, called “paroxysms”.On 3rd July 2019 a paroxysm without long-term precursors has occurred, followed by lava flows from a vent localized in the SW crater area and sporadically from the NE one. Afterwards, on 28th August 2019, a new paroxysmal explosion has occurred followed by strong volcanic activity, culminating with a lava flow from the SW-Central crater area.This study is focusing on environmental aftermath of the 2019 Stromboli eruptions. The analysis of Land Cover (LC) and Land Use (LU) changes is used to describe the impact on the environment of the island. The detection of impacted areas is mainly based on the integration of very high-spatial-resolution PLEIADES-1, moderate-spatial-resolution SENTINEL-2 satellite imagery, and field surveys. Normalized Burn Ratio (NBR), Normalized Difference Vegetation Index (NDVI), and Relativized Burn Ratio (RBR) were used to map the areas covered by fires. NBR easily allows to easily identify the areas impacted by wildfire and the degree of severity of the damage. This index is calculated on two SENTINEL-2 images acquired on different dates before and after the fire (after a not excessively high number of days, especially if the area affected by the fire consists mainly of pasture or low bush). RBR is obtained as the difference between the NBR index of the images acquired before and after the event. LC and LU classifications has involved the detection of new classes whose details have been calibrated on different reduction scales from 1:2.000 to 1:10.000, following the environmental units that made up the Strombolian landscape. New LC and LU classifications are the result of the intersection between classes of CORINE Land Cover project (CLC) and local landscape patterns. Field survey has been useful to conduce semi-structured interviews to the local population; the purpose of the social investigation was to collect detailed and direct information about damages.The most impacted areas by tephra fallout are located in the south-western and southern part of the island, nearby the village of Ginostra. The results of multi-temporal comparison show that fire-damaged areas amount to 39% of the total area of the island. Artificial areas have not been particularly impacted (max 14% of decrease), whereas agricultural and semi-natural vegetated areas show a much more consistent decrease of 34% and 81%, respectively.

Given a landslide, which are the constituent materials? How are the material inhomogeneities distributed? Which are their properties? What are the deformation processes? How large are the boundaries or how depth is/are the slip surface/s? Answering these questions is not a simple goal. Therefore, since the ‘70s, the international community (mainly geophysicists and lower geologists and geological engineers) has begun to employ, together with other techniques, active and passive geophysical methods to characterize and monitor landslides. Both the associated advantages and limitations have been highlighted over the years, but some drawbacks are still open.On the basis of the more recent landslides classification by Hungr et al. dated 2014, an analysis of about 120 open access papers published in international journals between the 2007 and the 2018 has been carried out. The aim of this review work was to evaluate the geophysical community efforts in overcoming the geophysical technique limitations highlighted in the conclusion section of the review of 2007 by Jongmans and Garambois. These drawback can be summarized ad follow: 1) geophysicists have to make an effort in the presentation of their results; 2) the resolution and the penetration depth of each method are not systematically discussed in an understandable way; 3) the geological interpretation of geophysical data should be more clearly and critically explained; 4) the challenge for geophysicists is to convince geologists and engineers that 3D and 4D geophysical imaging techniques can be valuable tools for investigating and monitoring landslides; and 5) efforts should also be made towards obtaining quantitative information from geophysics in terms of geotechnical parameters and hydrological propertiesMoreover, the review work highlighted that the most studied landslides are those of the flow type and fall type for the “soil” and “rock” category, respectively. From the “employed method” point of view, active and passive seismic methods are the most employed in landslide characterization and monitoring. The latest method is also able to remotely detect events that might otherwise go unnoticed for weeks or months, and therefore, it is widely employed. The three more frequently applied techniques to characterize and monitor the slope deformation are electrical resistivity tomography, seismic noise, and seismic refraction. Finally, the main conclusion is that independently of the applied technique/s or the landslide type, a very accurate and high-resolution survey could be performed only on a small landslide portion, as it is costly and time-consuming, even though geophysical techniques are defined as cost and time effective compared to traditional field methods.

This study focuses on the July-August 2019 eruption-induced wildfires at the Stromboli island (Italy). The analysis of land cover (LC) and land use (LU) changes has been crucial to describe the environmental impacts concerning endemic vegetation loss, damages to agricultural heritage, and transformations to landscape patterns. Moreover, a survey was useful to collect eyewitness accounts aimed to define the LU and to obtain detailed information about eruption-induced damages. Detection of burnt areas was based on PLÉIADES-1 and Sentinel-2 satellite imagery, and field surveys. Normalized Burn Ratio (NBR) and Relativized Burn Ratio (RBR) allowed mapping areas impacted by fires. LC and LU classification involved the detection of new classes, following the environmental units of landscape, being the result of the intersection between CORINE Land Cover project (CLC) and local landscape patterns. The results of multi-temporal comparison show that fire-damaged areas amount to 39% of the total area of the island, mainly affecting agricultural and semi-natural vegetated areas, being composed by endemic Aeolian species and abandoned olive trees that were cultivated by exploiting terraces up to high altitudes. LC and LU analysis has shown the strong correlation between land use management, wildfire severity, and eruption-induced damages on the island.

Detection, forecasting, early warning, and effective monitoring are key aspects for the delimitation of sinkhole-prone areas and for susceptibility assessment and risk mitigation. To attain these goals, direct and indirect techniques can be employed, and the integration of different indirect/non-invasive geophysical methods including 2D- and 3D-electrical resistivity tomography, microgravity, and single-station seismic noise measures was carried out at “Il Piano” (Elba Island – Italy), where at least nine sinkholes occurred between 2008 and 2014. The most likely origin for these sinkholes had been considered related to net erosion of sediment from the alluvium, caused by downward water circulation between the aquifer hosted in the upper layer (Quaternary alluvial deposits) and that in the lower (Triassic brecciated dolomitic limestone and Cretaceous slate). The integrated geophysical survey, therefore, was carried out a) to differentiate shallower from deeper geological layers, b) to detect possible cavities that could evolve into sinkholes, c) to suggest possible triggers, and d) to delimit the sinkhole-prone area. The results of the integrated geophysical surveys suggest that the study area is mainly characterised by paleochannels, and that the sinkhole-prone area boundaries correspond to these paleochannels.

Between 2008 and 2014, nine sinkholes occurred in northeastern Elba Island (Tuscany, Italy), an area with mostly flat terrain (called “Il Piano”) separating the municipalities of Rio nell’Elba and Rio Marina. The last sinkhole damaged the only road (SP26) between the harbour of Rio Marina and the northwestern part of the island. A bypass was immediately built, but the SP26 remains closed. Considering that sinkholes could be densely clustered in sinkhole prone areas, their detection and forecasting are key aspects of local administrative policies. In this paper, we present the results of an integrated geophysical survey aimed at (i) characterizing the geology of the area surrounding the SP26, and (ii) assessing the subsoil void hazard around the road system to support the decision to replace or restore the SP26. Therefore, for the purposes of this research, 120 single-station seismic noise measurements were taken following the horizontal-to-vertical spectral ratio (H/V) or Nakamura technique, while eight 2D electrical resistivity tomography (ERT) and 17 3D-ERT/induced polarisation measurements were also carried out in the study area. The H/V method allowed the estimation of the mean thickness of the alluvium, whereas the 2D/3D-ERTs and IPTs permitted the characterisation of the electrical behaviours of the materials and the localisation of the lenticular sand and gravel bodies within a sandy silt layer. The large amount of collected data made the zonation of the subsoil void hazards possible.

We communicate the results of a preliminary investigation aimed at improving a state-of-the-art RSLEWS (regional-scale landslide early warning system) based on rainfall thresholds by integrating mean soil moisture values averaged over the territorial units of the system. We tested two approaches. The simplest can be easily applied to improve other RSLEWS: it is based on a soil moisture threshold value under which rainfall thresholds are not used because landslides are not expected to occur. Another approach deeply modifies the original RSLEWS: thresholds based on antecedent rainfall accumulated over long periods are substituted with soil moisture thresholds. A back analysis demonstrated that both approaches consistently reduced false alarms, while the second approach reduced missed alarms as well.

The paper presents a simple yet robust frame model to be used as an alternative to continuous 2D or 3D finite element models for the purpose of analyzing multi-storey cross-laminated timber (CLT) shearwalls with openings when subjected to lateral loads. The proposed model is applicable to monolithic CLT walls and takes into account the mechanical interaction between wall segments and lintel/parapet elements as well as the non-linear behaviour of the mechanical anchors, while the contribution of the vertical load is omitted. Pushover numerical analyses were conducted on the proposed equivalent frame model (EFM) and 2-D finite element model, and the results showed good agreement between the two models along the entire force-displacement curves. The failure conditions were found to be consistent in all cases, and the distribution of the internal forces were found to be reasonable. The proposed EFM was also compared with published test results on CLT shearwalls and the fit was deemed reasonable, with a slight tendency to underestimating the ultimate capacity of the shearwalls.

An investigation of the mechanical behaviour of CLT shearwalls, where either door or window openings are cut out of the panel, is undertaken. The main aim of the study is to investigate failure modes related to either mechanical anchor or CLT panel, based on the geometrical dimensions and mechanical properties of shearwall. The results of six full-scale monolithic CLT shearwalls with window or door openings are presented and discussed. The results obtained from the full-scale shearwall tests are used to validate a proposed numerical model, where input parameters, such as the mechanical properties of the CLT panels and mechanical anchors, are obtained from component level tests on beams and connections in isolation. The study shows that differently from single-panel shearwalls with no openings, brittle failure in the CLT panels is a possible mode of failure, which needs to be considered in design. The failure mode in the CLT panels is observed to occur either in bending or net shear in the lintel beams. The proposed numerical procedure is found capable of estimating the maximum load with reasonable accuracy, and the model predictions of the failure mode, number of centre of rotations, and the overall deformation of the CLT panel are accurate for all the studied specimens.

A big challenge in terms or landslide risk mitigation is represented by increasing the resiliency of society exposed to the risk. Among the possible strategies with which to reach this goal, there is the implementation of early warning systems. This paper describes a procedure to improve early warning activities in areas affected by high landslide risk, such as those classified as critical infrastructures for their central role in society. This research is part of the project LEWIS (Landslides Early Warning Integrated System): An Integrated System for Landslide Monitoring, Early Warning and Risk Mitigation along Lifelines. LEWIS is composed of a susceptibility assessment methodology providing information for single points and areal monitoring systems, a data transmission network and a data collecting and processing center (DCPC), where readings from all monitoring systems and mathematical models converge and which sets the basis for warning and intervention activities. The aim of this paper is to show how logistic issues linked to advanced monitoring techniques, such as big data transfer and storing, can be dealt with compatibly with an early warning system. Therefore, we focus on the interaction between an areal monitoring tool (a ground-based interferometric radar) and the DCPC. By converting complex data into ASCII strings and through appropriate data cropping and average, and by implementing an algorithm for line-of-sight correction, we managed to reduce the data daily output without compromising the capability for performing.

On 4th November 2010, a debris flow detached from a large debris cover accumulated above the lowermost portion of the Rotolon landslide (Vicentine Pre-Alps, NE Italy) and channelized in the valley below within the Rotolon Creek riverbed. Such event evolved into a highly mobile and sudden debris flow, damaging some hydraulic works and putting at high risk four villages located along the creek banks. A monitoring campaign was carried out by means of a ground based radar interferometer (GB-InSAR) to evaluate any residual displacement risk in the affected area and in the undisturbed neighbouring materials. Moreover, starting from the current slope condition, a landslide runout numerical modelling was performed by means of DAN-3D code to assess the impacted areas, flow velocity, and deposit distribution of the simulated events. The rheological parameters necessary for an accurate modelling were obtained through the back analysis of the 2010 debris flow event. Back analysis was calibrated with all of the available terrain data coming from field surveys and ancillary documents, such as topographic, geomorphological and geological maps, with pre- and post-event LiDAR derived DTMs, and with orthophotos. Finally, to identify new possible future debris flow source areas as input data for the new modelling, all the obtained terrain data were reanalysed and integrated with the GB-InSAR displacement maps; consequently, new simulations were made to forecast future events. The results show that the integration of the selected modelling technique with ancillary data and radar displacement maps can be a very useful tool for managing problems related to debris flow events in the examined area.

The authors have drawn up the Map of Vulnerability to Pollution for groundwater of the Apuo-Versilia coastal Plain using the SINTACS method. The availability of a large number of subsoil data (stratigraphic columns and piezometric surveys) integrated in a GIS environment, has allowed to obtaining a large detail map on an extended area (about 152 Km2). Vulnerability rates from high to very high prevail in much part of the Plain; this poses a risk for groundwater, which represent an important resource for civil water supply.

Landslide deformations involve approximately all geological materials (natural rocks, soil, artificial fill, or combinations of these materials) and can occur and develop in a large variety of volumes and shapes. The characterization of the material inhomogeneities and their properties, the study of the deformation processes, and the delimitation of boundaries and potential slip surfaces are not simple goals. Since the ‘70s, the international community (mainly geophysicists and lower geologists and geological engineers) has begun to employ, together with other techniques, geophysical methods to characterize and monitor landslides. Both the associated advantages and limitations have been highlighted over the years, and some drawbacks are still open. This review is focused on works of the last twelve years (2007-2018), and the main goal is to analyse the geophysical community efforts toward overcoming the geophysical technique limitations highlighted in the 2007 geophysics and landslide review. To achieve this aim, contrary to previous reviews that analysed the advantages and limitations of each technique using a “technique approach,” the analysis was carried out using a “material landslide approach” on the basis of the more recent landslides classification.

Nowadays many developing countries need effective measures to reduce the disaster related risks. Structural interventions are the most effective to achieve these aims. Nevertheless, in the absence of adequate financial resources different low-cost strategies can be used to minimize losses. The purpose of this paper is to demonstrate that the disaster risk reduction can be gathered building a community coping capacity. In the case study, flood and seismic analyses have been carried out using relatively simple and low-cost technologies, fundamental for governments and research institutions of poorly developed countries. In fact, through the acquisition and dissemination of these basic information, a reduction of vulnerability and risk can be achieved. In detail, two methodologies for the evaluation of hydraulic and seismic vulnerability were tested in the Dajç municipality (Northern Albania), a high-seismicity region that is also severely affected by floods. Updated bathymetric, topographic and hydraulic data were processed with HEC-RAS software to identify sites potentially affected by dykes overflowing. Besides, the soil-structure interaction effects for three strategic buildings were studied using microtremors and the Horizontal to Vertical Spectral Ratio method. This flood and seismic vulnerability analysis was then evaluated in terms of costs and ease of accessibility in order to suggest the best use both of the employed devices and the obtained information for designing good civil protection plans and to inform the population about the right behaviour in case of threat.

On 10 March 2010, because of the heavy rainfall in the preceding days, the Montaguto landslide (Southern Italy) reactivated, affecting both state road 90 Delle Puglie and the Rome–Bari railway. A similar event occurred on May 2005 and on September 2009. As a result, the National Civil Protection Department (DPC) started an accurate monitoring and analysis program. A monitoring project using the GB-InSAR (ground-based interferometric synthetic aperture radar) system was emplaced to investigate the landslide kinematics, plan urgent safety measures for risk mitigation and design long-term stabilization work.Here, we present the GB-InSAR monitoring system results and its applications in the observational method (OM) approach. GB-InSAR is an established instrument for long-term campaigns aimed at early warning and monitoring during construction works. Our paper further develops these aspects in that it highlights how the OM based on the GB-InSAR technique can produce savings in terms of cost and time in engineering projects without compromising safety. This study focuses on the key role played by the monitoring activities during the design and planning activities, with special reference to the emergency phase.

The superimposition of geological formations with marked contrast in geotechnical properties presents one of the most critical environments for slope instability due to the different response of the materials to the applied disturbances. Moreover, the above-mentioned geological setting is often associated with high risk conditions, since many isolated rock slabs located at a higher altitude than the surrounding countryside have been sites of historical towns or buildings. The purpose of the present paper is to investigate the mechanisms determining instability in rock slabs overlying a soft substratum, with reference to two cultural heritage sites in Malta. Accurate investigations have been carried out to evaluate the geological, geotechnical and geomechanical properties together with the main geomorphological features of the soft clayey substratum and the overlying limestone rock mass. The main instability processes have thus been identified and investigated through kinematic analyses and numerical modeling, combined with a 1992–2001 Persistent Scatterers monitoring of ground displacements. The study constitutes the basis for the subsequent restoration works.

We propose a simple snow accumulation-melting model (SAMM) to be applied at the regional scale in conjunction with landslide warning systems based on empirical rainfall thresholds. SAMM follows an intermediate approach between physically based models and empirical temperature index models. It is based on two modules modelling the snow accumulation and the snowmelt processes. Each module is composed by two equations: a conservation of mass equation is solved to model snowpack thickness and an empirical equation for the snow density. The model depends on 13 empirical parameters, whose optimal values were defined with an optimization algorithm (simplex flexible) using calibration measures of snowpack thickness. From an operational point of view, SAMM uses as input data only temperature and rainfall measurements, bringing the additional advantage of a relatively easy implementation. The snow model validation gave satisfactory results; moreover we simulated an operational employment in a regional scale landslide early warning system (EWS) and found that the EWS forecasting effectiveness was substantially improved when used in conjunction with SAMM.

Sinkholes represent a geological risk that is often underrated, mainly due to its very localized nature. In fact, sinkholes occur only under particular circumstances and typically affect relatively small areas. Despite these characteristics, the difficulty in forecasting the precise location and timing of their sudden collapse creates serious problems for civil protection authorities and urban planners. In this framework, identifying the mechanism and thus the triggering factor of sinkholes is strategically pivotal in developing management plans. The present paper addresses the sinkhole-prone area of Il Piano (Elba Island, Central Italy). The integration of hydrogeological surveys, coupled with a thorough study of historical maps and aerial photographs, suggests that the main triggering factor in this area may not be related to water pumping from the karst aquifer, as initially hypothesized. Instead, sinkholes appear to be caused by ravelling and erosive processes occurring entirely in the sedimentary cover when heavy rainfall induces water overpressure within the superficial aquifer.

We map and monitor the condition of linear structures using Measurement Points (MPs) from satellite Interferometric Synthetic Aperture Radar (InSAR), and deal with the uncertainty of localising the detected deformation along the building elevation. We combine spatial information of the MPs with elevation measurements collected by Real Time Kinematic (RTK) GPS surveying to understand where structural motions occurred. The MPs are geolocated along the z-direction by exploiting their height information (hMP) compared to the elevation of the surveyed buildings and surrounding ground (hGPS). This approach aims to find a good compromise between the required accuracy and repeatability, and the advantages of reduced time-consumption and cost-effectiveness offered by RTK GPS. Reliability of the method is proved via the experiment on the Roman Aqueducts in the southern peri-urban quarters of the city of Rome, Italy. We focus on the linear man-made structures of the ancient to modern aqueduct systems. These are challenging anthropogenic features to monitor with InSAR due to their huge extent, variety of condition and architectural complexity. Of the total 13,519 MPs retrieved from SqueeSAR™ processing of 87 RADARSAT-1 Fine Beam Mode 3 ascending scenes (2003–2010), the MPs spatially attributed to the local linear features and the surroundings are analysed with regard to: (i) their densities against building type, structure planimetric orientation and vegetation coverage; and (ii) their height distribution against RTK GPS micro-topographic surveying in seven sample areas. Numerical analysis of hMP–hGPS pairs result in high correlation (R2 equals 0.970), and their cross-comparison allows validation of 3D geolocation of the MPs, also demonstrating the usefulness of complementary surveying by laser distance meter device whenever RTK GPS is not feasible. Cross-referenced hMP values are then used to reclassify the MPs and generate final map products to support the design of in-situ inspection activities. We discuss beneficial impacts for condition monitoring and assessment at the scale of single building through the examples of the medieval tower Torre del Fiscale and the Roman arcades of the Claudian Aqueduct. The MP height information improves the understanding of the deformation estimates, and also contributes to address hazard mitigation measures and restorations.

We improved a state-of-art RSLEWS (regional scale landslide early warning system) based on rainfall thresholds by integrating punctual soil moisture estimates. We tested two approaches. The simplest can be easily applied to improve other RSLEWS: it is based on a soil moisture threshold value under which rainfall thresholds are not used because landslides are never expected to occur. Another approach deeply modifies the original RSLEWS: thresholds based on antecedent rainfall accumulated over long periods were substituted by soil moisture thresholds. A back analysis demonstrated that both approaches reduced consistently false alarms, while the second approach reduced missed alarms as well.