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In this paper, we present the upgraded version of RockGIS, a stochastic program for the numerical simulation of rockfalls and their fragmentation, based on a fractal model. The code has been improved to account for a range of fragmentation scenarios, depending on the impact conditions. In the simulation, the parameters of the fractal fragmentation model that define the sizes of the generated fragments were computed at each impact according to the kinematic conditions. The performance of the upgraded code was verified and validated by real-scale rockfall tests performed in a quarry. The tests consisted of the release of 21 limestone blocks. For each release, the size and spatial distribution of the fragments generated by the impacts were measured by hand and from orthophotos taken via drone flights. The trajectories of the blocks and the resulting fragments were simulated with the code and calibrated with both the volume distribution and the runout distances of the fragments. Finally, as all the relevant rockfall parameters involved were affected by strong uncertainty and spatial variability, a parametric analysis was carried out and is discussed. This work has been carried out with the support of the Spanish Ministry of Economy and Competitiveness thanks to a fellowship to the first author (BES-2014-069795) and in the framework of the research project RockModels (Ref. BIA2016-75668-P, AEI/FEDER, UE). The collaboration of Canteras Hermanos Foj (Barcelona metropolitan area, Spain) is gratefully acknowledged.

Risk management due to natural hazards is a multidimensional and complex problem since it requires the knowledge and experience of several disciplines. The effectiveness of risk management can be analyzed, inviting to the action through weakness identification of the urban area. This article proposes a methodology based on the morphological analysis to support the decision-making on disaster risk management, taking as a starting point the results of a holistic evaluation of the seismic risk. The results of the holistic evaluation of risk are achieved aggravating the physical risk using the contextual conditions, such as the socio-economic fragility and the lack of resilience. In consequence, the risk mitigation can be performed through the reduction of the potential damage and consequences involved; and the improvement of social conditions. The proposed methodology allows prioritizing the risk reduction strategies according to i) performance level of component indicators involved into the Disaster Risk Management index, D R M i ; ii) physical risk factors dependent from the potential damages, and iii) aggravating factors involved in the aggravating coefficient. Moreover, it involves 35 strategies to reduce the physical risk and the aggravating social conditions of the urban area. The proposed methodology has been applied to the city of Merida (Venezuela), located within an area of high seismic activity. The performance level of the indicators involved in the D R M i was evaluated by a survey to local experts. As a result, eleven strategies have been identified to reduce the potential damage and to improve the social conditions of this city.

The basic input when seismic risk is estimated in urban environments is the expected physical damage level of buildings. The vulnerability index and capacity spectrum-based methods are the tools that have been used most to estimate the probability of occurrence of this important variable. Although both methods provide adequate estimates, they involve simplifications that are no longer necessary, given the current capacity of computers. In this study, an advanced method is developed that avoids many of these simplifications. The method starts from current state-of-the-art approaches, but it incorporates non-linear dynamic analysis and a probabilistic focus. Thus, the method considers not only the nonlinear dynamic response of the structures, modeled as multi degree of freedom systems (MDoF), but also uncertainties related to the loads, the geometry of the buildings, the mechanical properties of the materials and the seismic action. Once the method has been developed, the buildings are subjected to earthquake records that are selected and scaled according to the seismic hazard of the site and considering the probabilistic nature of the seismic actions. The practical applications of the method are illustrated with a case study: framed reinforced concrete buildings that are typical of an important district, the Eixample, in Barcelona (Spain). The building typology and the district were chosen because the seismic risk in Barcelona has been thoroughly studied, so detailed information about buildings&rsquo, features, seismic hazard and expected risk is available. Hence, the current results can be compared with those obtained using simpler, less sophisticated methods. The main aspects of the method are presented and discussed first. Then, the case study is described and the results obtained with the capacity spectrum method are compared with the results using the approach presented here. The results at hand show reasonably good agreement with previous seismic damage and risk scenarios in Barcelona, but the new method provides richer, more detailed, more reliable information. This is particularly useful for seismic risk reduction, prevention and management, to move towards more resilient, sustainable cities.

Document intern presentat al European Convention for Constructional Steelwork. Technical Committee TC8. Stability. This document presents an integration of measurement-to-design procedures related to structural analysis of tubular frames. TLS-based data-gathering and the automated transformation of the corresponding point clouds to as-built realistic BIM representations of the steel structures were performed. The measurement corresponds to an experimental program on four stainless steel frames. Point-cloud data was gathered during several test stages, including the unloaded case. Subsequently, a set of mathematical processing of the results is performed for the sake of generating realistic wire models. The automatic generation of these structures is developed within algorithmic modelling environments. The imperfection patterns are identified, processed and analyzed using comparison benchmarks. This experimental programme was developed in the frame of the Project BIA2016-75678-R, AEI/FEDER, UE “Comportamiento estructural de pórticos de acero inoxidable. Seguridad frente a acciones accidentales de sismo y fuego”, funded from the MINECO (Spain).

Terrestrial Laser Scanners (TLS) provide manifold possibilities in construction sites. In buildings assembled with steel frames, the “as-built” configuration of the structure can be virtualized by means of TLS measurements in the form of digital 3D point cloud data. This paper presents an integration of procedures related to the reproduction of realistic wire representations of steel frames. This integration encompasses the use of terrestrial laser scanning (TLS) measurements and the development of BIM-friendly wire models based on these measurements. These models are intended to be used in subsequent geometrically nonlinear analysis of the frames using similar BIM environments. All measurements are taken on laboratory tests of sway and non-sway stainless steel subjected to vertical and lateral loading. The “as-built” geometrical initial conditions can be used for the development of models embedded within BIM platforms for their subsequent usage in structural verification. This experimental programme was developed in the frame of the Project BIA2016-75678-R, AEI/FEDER, UE “Comportamiento estructural de pórticos de acero inoxidable. Seguridad frente a acciones accidentales de sismo y fuego”, funded from the MINECO (Spain) and to which financial support is acknowledged. Special thanks to Josep Gili, Nieves Lantada and Albert Torrente members of the research group EGEO –UPC.

The final publication is available at Springer via http://dx.doi.org/10.1007/s10346-017-0832-9 During the night of the 21 August 2015, a debris flow took place in one of the presently most active ravines of the Pyrenees, the Portainé torrent (Eastern Pyrenees, Spain), and caused considerable damage to the road. Detailed information was gathered from the debris flow monitoring system recently installed in the torrent and field surveys. The monitoring system measures ground vibration at geophones and flow height at an ultrasonic sensor. Meteorological data showed that the debris flow was triggered by a convective rainstorm with a total rainfall amount of 29 mm. All these data provide information on the debris flow occurrence and dynamics. The analysis of the data showed that the debris flow had three different surges and mobilised a total volume of about 2130 m3. The front velocity in the monitoring reach was somewhat small (about 2 m/s) and the peak flow discharge comparatively low (about 13 m3/s). In addition, the debris flow was back-analysed by a numerical model calibrated by the observed event. The results of the simulation showed that a Voellmy fluid rheological model can represent considerably well the recorded and observed measurements, and the best-fit values were µ = 0.28 and C = 8 m0.5/s. This research was funded by different research projects of the Spanish Ministry of Science and Innovation (DEBRISSTART: CGL2011-23300; CHARMA: CGL2013-40828-R, and SMuCPhy: BIA2015-67500-R) and the thematic network PYRMOVE. We also thank the Catalan Meteorological Service (www.meteocat.es) for data supply and Carles Fañanás for valuable information on the recent and historic events

The final publication is available at Springer via http://dx.doi.org/10.1007/s10518-018-0516-4 Risk assessment and management is an important step towards resilient and sustainable cities. Among many other perils, both natural and manmade, seismic risk is a major threat for resilience and sustainability. In recent decades, several methods for seismic risk assessment have been proposed, including the well-known Vulnerability Index Method (VIM). In this study, a probabilistic version of the VIM, which we call the Vulnerability Index Method-Probabilistic (VIM_P), is proposed. The VIM_P requires essential information on the seismic hazard and on the vulnerability of the building stock. Seismic hazard is determined using the exceedance rates of macroseismic intensities, as defined in the European Macroseismic Scale (EMS). Seismic vulnerability is defined by means of vulnerability probability density functions (pdf) that describe the probability distribution of the corresponding vulnerability index. Beta-like functions are used for these pdfs. VIM_P quantifies seismic vulnerability by means of three vulnerability curves, Lower, Best and Upper, according to the quantity and quality of available information, thus allowing three estimates of seismic vulnerability and risk. Then, seismic risk is computed via the convolution of seismic hazard and seismic vulnerability, considering semi-empirical damage functions. Seismic risk is given through the exceedance frequencies of the damage grades. To highlight the capabilities of the VIM_P, the seismic risk of about 70,000 residential buildings in Barcelona was assessed. According to the results, the exceedance frequency of the collapse damage state for more than the 50% of the buildings in the Eixample district would be greater than 1 × 10-5. This confirms the relatively high seismic risk in the city, mainly due to the high vulnerability of the built environment. Specific software, USERISK20015, has been developed for routine applications of VIM_P. It is hoped that VIM_P and this new tool for seismic risk assessment will be useful to stakeholders and civil protection authorities for risk management and prioritizing actions that can help to create more resilient, sustainable cities.

This book brings together a series of theory and practice essays on risk management and adaptation in urban contexts within a resilient and multidimensional perspective. The book proposes a transversal approach with regard to the role of spatial planning in promoting and fostering risk management as well as institutions’ challenges for governing risk, particularly in relation to new forms of multi-level governance that may include stakeholders and citizen engagement. The different contributions focus on approaches, policies, and practices able to contrast risks in urban systems generating social inclusion, equity and participation through bottom-up governance forms and co-evolution principles. Case studies focus on lessons learned, as well as the potential and means for their replication and upscaling, also through capacity building and knowledge transfer. Among many other topics, the book explores difficulties encountered in, and creative solutions found, community and local experiences and capacities, organizational processes and integrative institutional, technical approaches to risk issue in cities. Thanks to University of Veracruz, Barcelona Supercomputing Center, CONACYT and PRODEP. This research has been partially funded by the Ministry of Economy and Competitiveness (MINECO) of the Spanish Government and by the European Regional Development Fund (FEDER) of the European Union (UE) through projects referenced as: CGL2011-23621 and CGL2015-65913 -P (MINECO /FEDER, UE).

The use of massive data capture techniques in architectural heritage has enhanced the development of new methodologies that have an important impact on their conservation and understanding. The research proposes the study of formal anomalies in the cloister of the Cathedral of Tarragona (c. 12th century). It is a relevant Gothic construction in Catalonia, with the special singularity that part of its structure is raised over an important pre-existing Roman wall. The investigation is based on a point cloud obtained with a terrestrial laser scanner (TLS) and the systematization of the 3D analysis methodology of the point cloud through different reference shapes. In general terms, the construction is in good condition, so the discrepancies between real construction and the shapes of reference are small, with some exceptions. Nevertheless, the different approximations used allowed us to identify some relevant features, such as the variability of the form of rib vaults, and the influence of the criteria used in the definition and location of reference forms.

Usually the seismic risk evaluation involves only the estimation of the expected physical damage, casualties or economic losses. This article corresponds to a holistic approach for seismic risk assessment which involves the evaluation of the social fragility and the lack of resilience. The complementary evaluation of social context aspects such as the distribution of the population, the absence of economic and social development, deficiencies in institutional management, and lack of capacity for response and recovery; is useful in order to have seismic risk evaluation suitable to support a decision making processes for risk reduction. The proposed methodology allows a standardized assessment of the social fragility and lack of resilience, by means of an aggravating coefficient of which summarizes the characteristics of the social context using fuzzy sets and Analytic Hierarchy Process (AHP). The selection of 20 social indicators is based on the indicators used by urban observatories of United Nations and other social researchers. These indicators are classified according to social item they describe, in six categories. Applying the determination level analysis, thirteen prevailing social indicators are selected. The proposed methodology has been applied in the cities of Merida (Venezuela) and Barcelona (Spain).

Real-scale fragmentation tests provide high quality data in order to study the fragmentation pattern of rock blocks. In the tests carried out, the initial rock mass, in terms of both volume and shape, was reconstructed by means of 3D photogrammetry. The fragments size distribution of the bocks tested was measured by hand using a tape. The drop tests were performed in four different sites, releasing a total of 124 blocks and measuring 2907 fragments. The obtained fragment size distributions may be well fitted using power laws. The survival rate (Sr), which is the proportion of remaining block shows a wide range of values. Observing the fragment distribution, two parameters are needed to characterize the fragmentation: the number of fragments produced and Sr. The intensity of the fragmentation is expressed by the exponent of the fitted power laws. Although the results are highly variable and show a stochastic behavior of the fragmentation, we have identified different patterns that reflect some local test conditions This research was funded by the Spanish Ministry of Economy and Competitiveness and co-funded by the Agencia Estatal de Investigación (AEI) and The European Regional Development Fund (ERDF/FEDER, UE), grant number BIA2016-75668-P (AEI/FEDER, UE).

Basemaps are the main resource used in urban planning, building and infrastructure asset management. Therefore, they must be accurate and up to date to better serve citizens, contractors, property owners and town planning departments. Traditionally, they have been updated by aerial photogrammetry, but this is not always possible and alternatives need to be sought. In such cases, a useful option for large scales is the mobile mapping system (MMS). However, automatic extraction from MMS point clouds is limited by the complexity of the urban environment. Therefore, the influence of the urban pattern is analysed in three zones with varied urban characteristics: areas with high buildings, open areas, and areas with a low level of urbanization. In these areas, the capture and automatic extraction of 3D urban elements is performed using commercial software, which is useful for some elements but not for manholes. The objective of this study is to establish a methodology for extracting manholes automatically and completing hidden buildings' corners, in order to update urban basemaps. Shape and intensity are the main detection parameters for manholes, whereas additional information from satellite image Quickbird is used to complete the buildings. The worst rate of detection for all the extracted urban elements was found in areas of high buildings. Finally, the article analyses the computing cost for manhole extraction, and the economic cost and time consume of the entire process, including the proposed methodolgy using an MMS point cloud and the traditional survey in this case.

Landslides are one of the most common and dangerous threats in the world that generate considerable damage and economic losses. An efficient landslide monitoring tool is the Differential Synthetic Aperture Radar Interferometry (DInSAR) or Persistent Scatter Interferometry (PSI). However, landslides are usually located in mountainous areas and the area of interest can be partially or even heavily vegetated. The inherent temporal decorrelation that dramatically reduces the number of Persistent Scatters (PSs) of the scene limits in practice the application of this technique. Thus, it is crucial to be able to detect as much PSs as possible that can be usually embedded in decorrelated areas. High resolution imagery combined with efficient pixel selection methods can make possible the application of DInSAR techniques in landslide monitoring. In this paper, different strategies to identify PS Candidates (PSCs) have been employed together with 32 super high-spatial resolution (SHR) TerraSAR-X (TSX) images, staring-spotlight mode, to monitor the Canillo landslide (Andorra). The results show that advanced PSI strategies (i.e., the temporal sub-look coherence (TSC) and temporal phase coherence (TPC) methods) are able to obtain much more valid PSs than the classical amplitude dispersion (DA) method. In addition, the TPC method presents the best performance among all three full-resolution strategies employed. The SHR TSX data allows for obtaining much higher densities of PSs compared with a lower-spatial resolution SAR data set (Sentinel-1A in this study). Thanks to the huge amount of valid PSs obtained by the TPC method with SHR TSX images, the complexity of the structure of the Canillo landslide has been highlighted and three different slide units have been identified. The results of this study indicate that the TPC approach together with SHR SAR images can be a powerful tool to characterize displacement rates and extension of complex landslides in challenging areas

Fragmentation is a common feature of rockfalls that exerts a strong influence over the trajectories of the generated blocks, the impact energies and the runout. Real scale rockfall tests have traditionally been designed to evaluate the parameters of rockfall motion. In this contribution we present the results of a set of tests carried out in a limestone quarry that will be used to calibrate and support rockfall propagation models. A total of 56 blocks ranging between 0.2 and 4.8 m3 were dropped from two slope profiles with different morphology and falling height (16.5 and 27.5m total fall). Trajectories of the blocks and velocities were tracked with three high-speed video cameras. Some 43% of the blocks fragmented upon impact with the ground. Most of the blocks were massive limestone although a small percentage displayed a varying amount of finite fissures. The characteristics of the blocks, in particular the size and the Schmidt L hammer rebound were measured before the tests. The results show a lack of correlation between the Schmidt L hammer rebound and the disintegration of the blocks. Finally, it has been observed that the volume (size) distribution of the fragments resulting from the disintegration follow a power law with negative exponents ranging between 0.18 and 0.69. These results are consistent with the observed volume distributions in several natural rockfall events inventoried in limestone environments.

En aquest article s’aporta una proposta didàctica, la qual ens permet utilitzar l’assignatura de tecnologia com a principal matèria per poder treballar de manera interdisciplinària continguts del currículum de l’àmbit cientificotecnològic o matemàtic. Aquesta proposta didàctica es planteja des de la metodologia de l’aprenentatge basat en projectes (ABP) i el treball col·laboratiu. Aquestes metodologies són un marc idoni per integrar aquestes disciplines de l’àmbit cientificotecnològic i matemàtic. Al mateix temps, proporcionen un procés d’aprenentatge a l’alumnat que els permet desenvolupar múltiples competències, com, per exemple, el treball en equip, la presa de decisions, la iniciativa, etc. La proposta està dissenyada per a alumnes de tercer curs de l’educació secundària obligatòria i es treballaran algunes de les competències bàsiques dels àmbits cientificotecnològic i matemàtic. Al mateix temps, l’alumne serà capaç d’elaborar una sèrie de projectes que es podran relacionar amb assignatures del mateix nivell acadèmic o nivells predecessors i, així, reforçar conceptes generals treballats durant la formació acadèmica al centre i en el curs en qüestió. Alguns d’aquests projectes també pretenen conscienciar l’alumnat de l’ús i els beneficis de les energies renovables, el reciclatge o la reutilització de materials en la construcció dels seus projectes. [ANGLÈS] This article presents a didactic proposal which allows technology to be used as the main subject for interdisciplinary work on the curricular contents in the scientific-technological and mathematical fields. This didactic proposal is based on the project-based learning (PBL) methodology and collaborative work. These methodologies are an ideal framework to integrate these disciplines of the scientific-technological and mathematical fields. At the same time, they provide a learning process to students that allows them to develop multiple competences, such as teamwork, decision making, initiative, etc. The proposal is designed for students in the third year of compulsory secondary education and some of the basic competences of the scientific-technological and mathematical fields will be worked on. In turn, the student will be able to elaborate a series of projects that can be related to subjects of the same academic level or predecessor levels and thus reinforce the general concepts worked on during the academic education in the school and the year in question. Some of these projects also aim to raise awareness among students about the use and benefits of renewable energies, recycling or reuse of materials in the construction of their projects.

International audience

Rockfalls are frequent natural processes in mountain regions with the potential to produce damage. The quantitative risk analysis (QRA) is an approach increasingly used to assess risk and evaluate the performance of mitigation measures. In case of the fragmentation of the falling rock mass, some of the hypothesis taken in the QRA estimation for rockfalls have to be modified since a single block or rock mass can produce several fragments thus modifying the runout probability, the impact energies and exposure of the elements at risk. In this contribution, we present a procedure to account for the exposure in QRA analysis along linear paths using the fragmental rockfall propagation model RockGIS (Matas et al. 2017). The procedure is applied at the “Monasterio de Piedra”, Spain as part of a QRA.

Slope mass-wasting like shallow slides are mostly triggered by climate effects, such as rainfall, and soil–vegetation–atmosphere (SVA) interactions play a key role. SVA interactions are studied by a full-scale embankment with different orientations (North and South) and vegetation covers (bare and vegetated) in the framework of the prediction of climate change effects on slope stability in the Pyrenees. A clayey sand from the Llobregat river delta was used for the construction of the embankment and laboratory tests showed the importance of suction on the strength and hydraulic conductivity. Sixty sensors, which are mostly installed at the upper soil layer of the embankment, registered 122 variables at four vertical profiles and the meteorological station with a 5 min scan rate. Regarding temperature, daily temperature fluctuation at the shallow soil layer disappeared at a depth of about 0.5 m. There was great influence of orientation with much higher values at the South-facing slope (up to 55 °C at −1 cm depth) due to solar radiation. Regarding rainfall infiltration, only long duration rainfalls produced an important increase of soil moisture and pore water pressure, while short duration rainfalls did not trigger significant variations. However, these changes mostly affected the surface soil layer and decreased with depth.

The analysis of seismic signals obtained from near-source triaxial accelerometer recordings of two sets of single-block rockfall experiments is presented. The tests were carried out under controlled conditions in two quarries in northeastern Spain; in the first test (Foj limestone quarry, Barcelona), 30 blocks were released with masses ranging between 475 and 11,480 kg. The second test (Ponderosa andesite quarry, Tarragona) consisted of the release of 44 blocks with masses from 466 to 13,581 kg. An accelerometer and three high-speed video cameras were deployed, so that the trajectories, velocities, and block fragmentation could be tracked precisely. These data were used to explore the relationship between seismic energy and rockfall kinetics (the latter obtained from video analysis). We determined absolute and relative values of seismic energy and used them to estimate rockfall volumes. Finally, the seismic signature of block fragmentation was assessed in both the frequency and time domains. The ratios of seismic energy after impact to kinetic energy before impact ranged between 10-7 and 10-4. These variables were weakly correlated. The use of seismic energy relative to impacting kinetic energy was preferred for the estimation of volumes. Block fragmentation impacts were dominated by higher acceleration spectrum centroid frequencies than those of nonfragmentation impacts: 56.62 ± 2.88 and 48.46 ± 4.39 Hz at Foj and 52.84 ± 12.73 and 38.14 ± 4.73 Hz at Ponderosa.

This article presents a holistic and comprehensive approach for seismic risk assessment which involves the evaluation of the social fragility and the lack of resilience of the study area. That means, involves the characteristics of the social context that can exacerbated the situation when a hazardous event occurs. The proposed methodology allows a standardized assessment of the social fragility and lack of resilience, by means of an aggravation coefficient of which summarizes the characteristics of the social context using fuzzy sets and analytic hierarchy process. The selection of 20 social indicators is based on the indicators used by urban observatories of United Nations and other social researchers. These indicators are classified in six categories according to social item they describe: i) Dwelling, ii) Social development and poverty eradication, iii) Urban Planning, iv) Governance, v) Lack of resilience and vi) Demography. Applying the determination level analysis, thirteen prevailing social indicators are selected. The proposed methodology was applied to the city of Mérida (Venezuela). The average value of seismic physical risk was low and high for intensities VIII and IX respectively. However, parishes present results with important differences among them. The average value of the aggravation coefficient is medium. The average total seismic risk is moderate and very high for intensity VIII and IX respectively. According to the obtained results, the social context substantially aggravates the seismic physical risk in 5 of the 11 city parishes. Seven of them have a very high level of total seismic risk.

Licensee MDPI, Basel, Switzerland. This article presents a methodology to process information from a Terrestrial Laser Scanner (TLS) from three dimensions (3D) to two dimensions (2D), and to two dimensions with a color value (2.5D), as a tool to document and analyze heritage buildings. Principally focused on the loss of material in stone, this study aims at creating an evaluation method for loss control, taking into account the state of conservation of a building in terms of restoration, from studying the pathologies, to their identification and delimitation. A case study on the Cathedral of the Seu Vella de Lleida was completed, examining the details of the stone surfaces. This cathedral was affected by military use, periods of abandonment, and periodic restorations.

Prior to the application of any persistent scatterer interferometry (PSI) technique for the monitoring of terrain displacement phenomena, an adequate pixel selection must be carried out in order to prevent the inclusion of noisy pixels in the processing. The rationale is to detect the so-called persistent scatterers, which are characterized by preserving their phase quality along the multi-temporal set of synthetic aperture radar (SAR) images available. Two criteria are mainly available for the estimation of pixels' phase quality, i.e., the coherence stability and the amplitude dispersion or permanent scatterers (PS) approach. The coherence stability method allows an accurate estimation of the phase statistics, even when a reduced number of SAR acquisitions is available. Unfortunately, it requires the multi-looking of data during the coherence estimation, leading to a spatial resolution loss in the final results. In contrast, the PS approach works at full-resolution, but it demands a larger number of SAR images to be reliable, typically more than 20. There is hence a clear limitation when a full-resolution PSI processing is to be carried out and the number of acquisitions available is small. In this context, a novel pixel selection method based on exploiting the spectral properties of point-like scatterers, referred to as temporal sublook coherence (TSC), has been recently proposed. This paper seeks to demonstrate the advantages of employing PSI techniques by means of TSC on both orbital and ground-based SAR (GB-SAR) data when the number of images available is small (10 images in the work presented). The displacement maps retrieved through the proposed technique are compared, in terms of pixel density and phase quality, with traditional criteria. Two X-band datasets composed of 10 sliding spotlight TerraSAR-X images and 10 GB-SAR images, respectively, over the landslide of El Forn de Canillo (Andorran Pyrenees), are employed for this study. For both datasets, the TSC technique has showed an excellent performance compared with traditional techniques, achieving up to a four-fold increase in the number of persistent scatters detected, compared with the coherence stability approach, and a similar density compared with the PS approach, but free of outliers.

A rockfall is a mass instability event frequently observed in road cuts, open pit mines and quarries, steep slopes and cliffs. After its detachment, the rock mass may disaggregate and break due to the impact with the ground surface, thus producing new rock fragments. The consideration of the fragmentation of the rockfall mass is critical for the calculation of the trajectories of the blocks and the impact energies and for the assessment of the potential damage and the design of protective structures. In this paper, we present RockGIS, a GIS-based tool that simulates stochastically the fragmentation of the rockfall, based on a lumped mass approach. In RockGIS, the fragmentation is triggered by the disaggregation of the detached rock mass through the pre-existing discontinuities just before the impact with the ground. An energy threshold is defined in order to determine whether the impacting blocks break or not. The distribution of the initial mass between a set of newly generated rock fragments is carried out stochastically following a power law. The trajectories of the new rock fragments are distributed within a cone. The fragmentation model has been calibrated and tested with a 10,000 m3 rockfall that took place in 2011 near Vilanova de Banat, Eastern Pyrenees, Spain.

[EN] Determining the trajectory of a block that falls down on a slope is not straightforward due to the high number of variables involved. Because of this, the appropriate understanding of how these variables may affect the trajectories is required. In this work, we estimate some magnitudes that affect the trajectories of the blocks such as the coefficient of restitution and the energy thresholds for fragmentation of the blocks among others. We have chosen the controlled scenario of a quarry in which targets and high speed video cameras were arranged to capture images of the blocks falling from the top of a slope. The position of the blocks over time has been measured from video frames applying photogrammetric methods. From here, the velocities and the accelerations have been determined, and with the estimated mass of each block, we have calculated the energy balance., [ES] La trayectoria de un bloque que cae por un talud no es fácil de determinar porque influyen muchas variables difíciles de cuantificar. Ello requiere del conocimiento de cómo estas variables afectan a las trayectorias. En este trabajo se estiman algunas magnitudes que afectan la trayectoria de los bloques como son los coeficientes de restitución y los límites de energía para generar la fragmentación del bloque, entre otros. Para ello se ha escogido el entorno controlado de una cantera, en el que se han dispuesto dianas y cámaras de vídeo de alta velocidad, para capturar imágenes de las caídas de bloques lanzados desde lo alto de un talud. Hemos medido la posición del bloque respecto del tiempo a partir de los fotogramas de vídeo obtenidos, aplicando métodos fotogramétricos. A partir de aquí se determinan las velocidades y las aceleraciones y, con la estimación de la masa de cada bloque, hemos calculado los balances de energía., Este trabajo se enmarca dentro del proyecto de investigación titulado “Caracterización y modelización de los desprendimientos rocosos”, con acrónimo Rockmodels financiado por el Ministerio de Economía, Industria y Competitividad (BIA2016-75668-P).

This field trip has been devised as the closure of this sixth edition of the RocExs workshop, on the Wednesday May 24th. According to the purposes of this interdisciplinary meeting, most of the suggested topics for the workshop are tried to be present during the field trip: Rockfall characterization, inventory and mapping; testing and modeling; hazard and risk analyses; monitoring; large rockfall cases; protective measures; risk mitigation and management. We hope that you will enjoy this trip, both from technical point of view and leisure, because Montserrat Mountain is a special place where earth and heaven meet configuring captivating scenery. The rockfall risk in Montserrat must be managed properly in order to keep on enjoy-ing this cultural and natural heritage.

RESUMEN: Este proyecto de investigación estudia los mecanismos de la pérdida de suelos en zonas montañosas mediante un método multidisciplinar y el trabajo a diferentes escalas. Uno de los objetivos principales es analizar el efecto del cambio climático sobre estos mecanismos y buscar métodos de mitigación para afrontarlo correctamente. Se utilizan datos obtenidos mediante la auscultación de un experimento físico a gran escala y cuatro laderas y cuencas naturales situadas en el Pirineo Catalán, para alimentar y validar un modelo numérico innovador que implementa un módulo de interacciones suelo-vegetación-atmósfera. Finalmente, los resultados de la auscultación y de la modelización numérica se usarán para realizar una correlación de factores condicionantes de la inestabilidad con la ocurrencia espacio-temporal de deslizamientos superficiales utilizando técnicas SIG a escala regional. 1200

The Mediterranean city of Tarragona was a capital city in Roman times. Nowadays, the remains of the ancient constructions coexist with many subsequent buildings. This is the case of the Gothic Cathedral cloister, whose walls partially take advantage of the remains of the temenos 's wall. This paper focuses on the assessment of that unique overlapping of construction phases. The investigation is performed through an unprecedented topographical survey by means of massive data capture techniques. This information is the basis for the mechanical assessment of the equilibrium conditions of the northern corner of the gallery, which is performed on the well-known theoretical framework of limit analysis by means of thrust lines. The study allowed to enhance the understanding about the equilibrium conditions and the deformation processes of the gallery masonry elements, where the mechanical relation between the Roman and Gothic walls is essential.

Determinar el riesgo al que está expuesto un edificio o una infraestructura debido a los desprendimientos rocosos mediante la Evaluación Cuantitativa de Riesgo requiere estudiar la peligrosidad, que integra la magnitud del fenómeno y la probabilidad de ocurrencia. Hoy en día la mayoría de metodologías disponibles para realizar estudios de peligrosidad no consideran la fragmentación de los bloques durante su propagación por la ladera. Este proceso tiene implicaciones directas en el estudio de la peligrosidad ya que se pueden incrementar el número de fragmentos y las energías cinéticas de los bloques disminuyen al reducirse su tamaño. En esta contribución se presenta el diseño e implementación de un módulo de fragmentación en un programa de simulación de desprendimientos rocosos llamado RockGIS y su aplicación a un caso de estudio.

Rockfalls are frequent instability processes in road cuts, open pit mines and quarries, steep slopes and cliffs. The orientation and persistence of joints within the rock mass define the size of the kinematically unstable rock volumes and determine the way how the detached mass be-comes fragmented upon the impact on the ground surface. Knowledge of the size and trajectory of the blocks resulting from fragmentation is critical for calculating the impact probability and intensity, the vulnerability the exposed elements and the performance of protection structures. In this contribution we summarize the main goals and achievements of the RockRisk project. We focused on the characterization of the rockfall fragmentation by means of the analysis of the fracture pattern of intact rock masses, the development of a fragmentation model and its integration into rockfall propagation analysis. The ultimate goal of the project is to quantify risk due to rockfalls and develop tools for the improvement of prevention and for protection from its occurrence.

One of the main applications of SAR interferometry is the monitoring of hazard risks related with urban subsidence and landslide instabilities. The different sensors available offer different carrier frequencies, image swaths and resolutions. Depending on the extension of the area and phenomena to monitor, one particular mode can be more suitable than others. In this paper the benefits of high-resolution X-band for landslide monitoring is addressed. The selected mode is the experimental Staring-Spotlight of TerraSAR/TanDEM-X and the area under study the landslide of El Forn de Canillo (Andorra) that is perfectly oriented for orbital DInSAR processing. The paper demonstrates the benefits of high resolution data and the processing challenges that have to be addressed.

RESUMENLa caída de bloques de roca sobre infraestructuras y zonas urbanizadas causa elevados daños y alguna víctima cada año en nuestro país. Los modelos de propagación existentes no tienen en cuenta la fragmentación durante la caída, hecho que influye significativamente en las trayectorias, número de fragmentos y alcance y energía de los mismos. En este artículo presentamos los resultados de tres ensayos a escala real, enfocados a la caracterización de la fragmentación, llevados a cabo con tres litologías distintas. Los resultados de los ensayos han sido usados para construir y calibrar modelos de propagación que incluyen la fragmentación. En los ensayos se han lanzado un total de 100 bloques entre 0,2 y 4,8 m3 desde alturas entre 16 y 27,5 m. Antes de los lanzamientos, los bloques fueron caracterizados geométricamente (fotogrametría masiva envolvente) y geomecánicamente (esclerómetro Schmidt L). Las trayectorias se han seguido mediante 3 cámaras de alta velocidad. También se han tomado imágenes aéreas mediante un dron. Un 43% de los bloques calizos, un 27% de los bloques de dacitas y un 17% de los bloques graníticos se han fragmentado de manera significativa durante los lanzamientos. Se ha obtenido nula correlación entre el rebote del martillo L de Schmidt y la fragmentación de los bloques. Tras cada rotura, se han inventariado las dimensiones de los fragmentos finales, lo que ha permitido comprobar que su distribución (RBSD) puede ajustarse mediante modelos tipo

Montserrat Mountain is located near Barcelona in Catalonia, in the northeast of Spain, and its massif is formed by conglomerate interleaved by siltstone/sandstone with steep slopes very prone to rockfalls. The increasing number of visitors in the monastery area, reaching 2.4 million per year, has highlighted the risk derived from rockfalls for this building area and also for the terrestrial accesses, both roads and the rack railway. A risk mitigation plan has been launched, and its first phase during 2014-2016 has been focused largely on testing several monitoring techniques for their later implementation. The results of the pilot tests, performed as a development from previous sparse experiences and data, are presented together with the first insights obtained. These tests combine four monitoring techniques under different conditions of continuity in space and time domains, which are: displacement monitoring with Ground-based Synthetic Aperture Radar and characterization at slope scale, with an extremely non-uniform atmospheric phase screen due to the stepped topography and atmosphere stratification; Terrestrial Laser Scanner surveys quantifying the frequency of small or even previously unnoticed rockfalls, and monitoring rock block centimetre scale displacements; the monitoring of rock joints implemented through a wireless sensor network with an ad hoc design of ZigBee loggers developed by ICGC; and, finally, monitoring singular rock needles with Total Station.

[EN] Before starting a rehabilitation project for a monument the graphic information about it has to be available. Nowadays, different techniques allow us to obtain three-dimensional models with a different accuracy level and runtimes. This paper shows the work carried out to generate the graphic information as complete as possible (vertical and horizontal maps, sections and 3D models) for the rehabilitation of the tomb of Queen Elisenda in the Pedralbes Monastery, Barcelona (Spain). Laser scanning, photogrammetry and topography have been used for the data capture. That data will allow the analysis of the monument construction process. The models from photogrammetry and laser scanning will be compared., [ES] Antes de comenzar un proyecto de rehabilitación de un monumento tiene que estar disponible su información. Actualmente, existen diferentes técnicas que permiten obtener datos 3D con un nivel de precisión alto y con tiempos de ejecución realmente optimizados. Este artículo muestra el trabajo llevado a cabo para generar la información gráfica más completa posible (alzados, planta, secciones y modelos 3D) para el proyecto de rehabilitación de la tumba de la reina Elisenda en el Monasterio de Pedralbes, Barcelona (España). Para ello se han utilizado diferentes técnicas de captura de datos espaciales (láser de barrido, fotogrametría y topografía). Estos datos permitirán el análisis y posible planteamiento del proceso de reconstrucción del monumento. Así mismo se plantea la comparación entre los resultados obtenidos para los modelos de los elementos empleando fotogrametría digital e instrumentos láser escáner.

3D surveys of archaeological elements and the construction of virtual models enable us to reconstruct historical sites. They provide useful data to select specific building processes. Photogrammetry and Terrestrial Laser Scanning (TLS) are the most common techniques to obtain synthetically heritage models. These techniques provide massive data which can only be managed by replacing them by primitive shapes, thereby obtaining more simple models and the explicit geometry of the element. Statistical and robust methods are used for this substitution, thereby avoiding the common errors due to measuring. Of these methods, the most widely used are the least-median-of-squares (LMedS) and the RANSAC method. Another computation method consists in recursive processes based on evolutive-type algorithms to adjust the model to the data captured. This paper describes two surface computation methodologies to determine the modelling of a column shaft located in temple G of the archaeological park of Selinunte (Sicily).

Seismic microzonation of urban areas is used to be determined from few soils’ response measurements in each area. In consequence, results can be considered correct only in the case of possible depth-dependent soils, being the existence of lateral soil changes the cause of imprecision. Ground-penetrating radar (GPR) could be a useful tool to determine, previously to the passive seismic measurements, the location of geological structures. Moreover, depending on the ground materials, the GPR energy is randomly backscattered. Consequently, the background noise in the radar scans increases. Therefore, the analysis of the amplitude of the noise could be a useful method to determine changes on the ground characteristics. The analysis of the background GPR amplitude noise is tested in two radar lines, crossing the city of Barcelona. The results show significant differences in the background noise amplitude in the A-scans that could be used to define zones in the city depending on the noise level. These changes on the amplitude are associated with the backscattered energy as a consequence of soil characteristics. Hence, the analysis of the variation in the background noise amplitude allows defining the possible location of subterranean streams, paleochannels, and other structures crossing the plain of the city. Radar results are also compared to ambient vibration measurements, using the spectral horizontal-to-vertical (H/V) quotient, and to historical and contemporary information. The application of the methodology underscores the ability of the evaluation of the backscattering associated with the background noise in the scans in the detection of sharp geological changes in sedimentary deposits.

Este estudio pretende relacionar los registros (marzo de 2013 a febrero de 2014) de dos mareógrafos situados en el Puerto de Barcelona y que se han denominado BCN2 y BCN3. El mareógrafo BCN2 pertenece a la RED de MAReógrafos de Puertos del Estado (REDMAR) y refiere los datos al NMMA1995 mientras que BCN3, propiedad de la Autoridad Portuaria de Barcelona, los refiere a la Red Topográfica del Puerto de Barcelona observada mediante técnicas GNSS. Ambos mareógrafos están separados unos 3Km. en línea recta y unos 8Km. por tierra. El objetivo ha sido determinar la diferencia existente entre los ceros de referencia de los dos mareógrafos. El nivel de mar observado por los mareógrafos, sin tener en cuenta la acción del oleaje, está afectado por la marea astronómica y la marea meteorológica. La marea meteorológica es de tipo aleatorio, por el contrario la marea astronómica es de carácter determinista y se puede resolver realizando el análisis de armónicos. Para ello, una vez realizado el control de calidad de los datos brutos, se utilizó la aplicación T_TIDE en MATLAB obteniendo como resultado para cada mareógrafo tres gráficas y dos ficheros. Las gráficas representan respectivamente el nivel del mar observado, la marea astronómica y la meteorológica o residuo y de los dos ficheros, uno corresponde al cálculo de los componentes armónicos, del que nos interesa la componente Z0 (nivel medio del mar) y el segundo contiene la componente meteorológica. Se puede concluir en que el cero de referencia de BCN3 está situado 0,096 metros por encima del NMMA 1995.

We discuss a taxonomy of different dynamical featuresin the ocean surface and provide some eddy and frontstatistics, as well as describing some events detected byseveral satellites and even with additional cruise observationsand measurements, in the North-west MediterraneanSea area between 1996 and 2012. The structureof the flows are presented using self-similar traces thatmay be used to parametrize mixing at both limits of the Ross by Deformation Radius scale, RL. Results showthe ability to identify different SAR signatures and at thesame time provide calibrations for the different local configurationsof vortices, spirals, Langmuir cells, oil spillsand tensioactive slicks that eventually allow the study ofthe self-similar structure of the turbulence. Dependingon the surface wind and wave level, and also on the fetch.the bathimetry, the spiral parameters and the resolution of vortical features change. Previous descriptions did not includethe new wind and buoyancy features. SAR imagesalso show the turbulence structure of the coastal area andthe Regions of Fresh Water Influence (ROFI). It is not eworthytt such complex coastal fielddependent behavioris strongly influenced by stratification and rotation of theturbulence spectrum is observed only in the range smallerthan the local Ross by deformation radius, RL. The measuresof diffusivity from buoy or tracer experiments areused to calibrate the behavior of different tracers and pollutants,both natural and man-made in the NW MediterraneanSea. Thanks to different polarization and intensitylevels in ASAR satellite imagery, these can be usedto distinguish between natural and man-made sea surfacefeatures due to their distinct self-similar and fractal as afunction of spill and slick parameters, environmental conditionsand history of both oil releases and weather conditions.Eddy diffusivity map derived from SAR measurementsof the ocean surface, performing a feature spatialcorrelation of the available images of the region are presented.Both the multi fractal discrimination of the localfeatures and the diffusivity measurements are importantto evaluate the state of the environment. The distributionof meso-scale vortices of size, the Ross by de for mationscale and other dominant features can be used to distinguishfeatures in the ocean surface. Multi-fractal analysisis then very use full. The SAR images exhibited a largevariation of natural features produced by winds, internalwaves, the bathymetric distribution, by convection, rain,etc as all of these produce variations in the sea surfaceroughness so that the topological changes may be studiedand classified. In a similar way bathimetry may bestudied with the methodology described here using thecoastline and the thal wegs as generators of local verticalvorticity.

Rockfalls are frequent instability processes in road cuts, open pit mines and quarries, steep slopes and cliffs. The attitude and persistency of joints within the rock mass define the size of kinematically unstable rock volumes. Furthermore, the rock block will eventually split in several fragments during its propagation downhill due its impact with the ground surface. Knowledge of the size, energy and trajectory of each block resulting from fragmentation is critical in determining the hazard of buildings and protection structures. The objective of this study is to simulate stochastically the fragmentation mechanism in rockfall propagation trajectories and in the calculation of impact energies in a GIS-Based tool which includes common modes of motion for falling boulders. A stochastic fragmentation model is proposed and tested to determine if it can simulate the fragmentation phenomena properly.

The use of Unmanned Aerial Vehicles, UAVs to image capture for monitoring natural hazards has had a major boost for its wide possibilities in the last decade. These are, for example, the studying and monitoring of unstable slopes, glaciers and rocky escarpments. Moreover, to evaluate the risk after a rockfall or debris flow event, for example measuring volume of displaced material, trajectories of blocks or building and/or infrastructure damaged. But the use of these devices requires a specific treatment regarding the studied case and geomatic techniques suitable to get the adequate precision of the movement, size of items or events to study. For each application it is necessary to determine what kind of capture is the most appropriate to obtain an optimal benefit-cost ratio. A comparison of the use of terrestrial photogrammetry, UAV photogrammetry and video from UAV has been done. The best result has been obtained combining techniques aerial and terrestrial since ground points with a best quality can be identified and measured and all the surface has a best image coverage.

Rainfall-induced flows and slides are hazardous processes in mountainous regions and suscep-tibility assessments with resulting maps are helpful tools for land-use planners. In the present study, all the available information on recent events has been gathered and incorporated in an inventory. The governing fac-tors of the 2262 entries were analyzed and preliminary susceptibility matrices were established. Two different terrain units were applied and compared: grid cells and first-order catchments. The results showed that slope angle between 30 and 35º and land cover classes like debris screes or grassland are the most significant fac-tors. In addition, the Melton Ratio higher than ~0.7 in the first-order catchments seems to be another critical parameter. Finally, two types of susceptibility maps were created, although the ones working with first-order catchments look more appropriate for the application at regional scale and the use for land-use planning.

When an urban development is planned the cartography of this territory is necessary, in the same way before starting a project to rehabilitate a monument the graphic information about it has to be available. At present, different techniques are available which allow to obtain three-dimensional models with a different accuracy level and runtimes. This paper shows the work carried out to obtain the graphic information and three-dimensional models that are necessary for the rehabilitation project of the tomb of Queen Elisenda in the Monastery of Pedralbes, Barcelona (Spain). This monument has the peculiarity of being symmetrical about the wall separating monastery church and the cloister. To do this, different techniques have been used that allow us to obtain an accurate model and as complete as possible, for the analysis of the construction process of the monument. In order to achieve the complete architectural survey the integration of laser scanning and photogrammetric data, and CAD models has been necessary. Due to the detail of the sculptures and the Queen’s sarcophagus two sensors, with different resolution, range and accuracy, have been used to obtain the laser scanning data. Stereo pairs have been taken to obtain the 3D model of these elements to complete the model and obtain an ortophotography. In this way, a comparative analysis of both techniques has been carried out, in order to decide which one is the suitable for certain application. This investigation has been restricted to the tomb, in the two symmetrical parts of the monument.

Este artículo presenta el proyecto desarrollado durante el año 2011 por las unidades y centros de formación de las universidades públicas catalanas. El proyecto se orienta a la mejora de la calidad del sistema de educación superior y de la actividad del profesorado universitario mediante planes de formación específicamente diseñados con esta finalidad, centrándose primeramente en la identificación de competencias docentes definidas por la comunidad académica. Partiendo del contexto de implementación del Espacio Europeo de Educación Superior se identifican aquellas competencias propias de la función docente, para que posteriormente puedan ser adquiridas, desarrolladas y evaluadas mediante la formación, identificando modelos, estrategias, instrumentos y recursos que lo permitan. El proceso de identificación de las competencias docentes del profesorado universitario se ha desarrollado partiendo de una revisión bibliográfica del estado del arte, para posteriormente ser modificada y validada por grupos de discusión conformados por expertos en competencias y formación docente. Los resultados de identificación de dichas competencias han sido finalmente refrendados mediante una encuesta respondida por una muestra representativa de la comunidad académica de las ocho universidades públicas catalanas. El objetivo fundamental del proyecto que aquí presentamos no es otro que el de contribuir a una formación de calidad del profesorado universitario, que permita la adquisición, desarrollo y evaluación de las competencias que, como docente, gran parte de la comunidad académica considera que debe poseer para el ejercicio de su labor profesional, definidas como: interpersonal, metodológica, comunicativa, de planificación y gestión de la docencia, de trabajo en equipo y de innovación.ABSTRACTIdentification of teaching skills in the implementation of training plans for university teaching staff.This article present the project developed in 2011 by units and training centers from all public universities in Catalonia. The project is devised towards the quality improvement of the higher education system and of the activity undertaken by the faculty at the university. In order to achieve these objectives, it focuses on the identification of teaching skills, defined by the academic community through training programs specifically designed for this purpose. Taking the implementation of the European Higher Education as starting point, the project intends to analyze the skills considered to belong by nature to the teaching task, as well as to define the necessary procedures to acquire, develop and evaluate them through training. At the same time it seeks to identify models, strategies, tools and resources. To this identification process we will make the necessary bibliographical research, in which the criteria of teaching excellence will allow us to select a representative sample of teachers. The selection will be performed through a survey and its quality will be validated by experts. Th e primary objective of the project shown here is basically to contribute to the quality training of university teachers, allowing the acquisition, development and evaluation of the skills considered essential by the academic community, in order to properly undertake their professional tasks, defined as: interpersonal, methodology, communication, planning and management of teaching, teamwork and innovation.