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Base de dades constituïda, per una matriu de 9 prototips de pòrtics dissenyats mitjançant DLA per a 11 nivells de dany (factor α), amb 6 pòrtics sotmesos a anàlisi no lineal temps història i 3 pòrtics amb anàlisi no lineal temps història juntament anàlisi push-over , consolidant un total de 132 respostes obtingudes. Les anàlisis inclouen efectes de degradació per histèresi model IMK. Base de datos constituida, por una matriz de 9 prototipos de pórticos diseñados mediante DLA para 11 niveles de daño (factor α), con 6 pórticos sometidos a análisis no lineal tiempo historia y 3 pórticos con análisis no lineal tiempo historia junto análisis push-over, consolidando un total de 132 respuestas obtenidas. Los análisis incluyen efectos de degradación por histéresis modelo IMK. Database consisting, of a matrix of 9 prototype portal frames designed by means of DLA for 11 damage levels (α factor), with 6 frames subjected to nonlinear time-history analysis and 3 frames with nonlinear time-history analysis together with pushover analysis, consolidating a total of 132 responses obtained. The analyses include hysteresis degradation effects by IMK model.

L’esllavissada del Forn de Canillo és una de les més grans del Pirineu amb un volum mobilitzat de 360 Mm3. L’esllavissada és inactiva en la seva gran part, excepte en dues zones. En una d'elles s'ha centrat aquest treball; es tracta del lliscament o lòbul de Cal Ponet -Cal Borronet, amb una velocitat mitjana d'entre 2-4 cm per any i amb un volum mobilitzat de 1,15 Mm3. Malgrat la seva petita velocitat, el lliscament causa regularment danys a una carretera i a un túnel. Per aquest motiu, el desplaçament i la piezometría s'han monitorat des de l'any 2005. El sistema d'auscultació s'ha anat completant amb el temps i s'ha pogut traçar un perfil geològic prou complet. Un aspecte clau en la previsió de la mobilitat i del risc de les esllavissades és obtenir els paràmetres resistents del terreny de manera realista, en particular, de l'angle de fricció residual. Freixa (2021) va realitzar una anàlisi retrospectiva mitjançant el mètode d'equilibri límit, amb un coneixement limitat del flux d'aigua en el lliscament, i va obtenir un rang de valors d'aquest angle entre 27 i 31°. L'objectiu essencial d'aquest treball ha estat aprofundir en el coneixement del comportament del lliscament. Per a això, s'ha aprofitat el registre més llarg de l'auscultació, i de mostres de nous sondejos. S'han realitzat diversos assajos de laboratori per a caracteritzar el material de la superfície de ruptura; en particular, assajos de tall anul·lar i directe per a determinar l'angle de fricció residual. Es van obtenir valors de 14-15  amb el tall anul·lar, i de 35 amb el tall directe, utilitzant diferents fraccions del material. El nucli d'aquest treball ha estat el modelatge del flux d'aigua en el lliscament i de l'estabilitat del lliscament. El Forn de Canillo landslide is one of the largest landslides in the Pyrenees with a mobilised volume of 360 Mm3. The landslide is largely inactive, except in two areas. One of these is the Cal Ponet-Cal Borronet landslide or lobe, with an average velocity of 2-4 cm per year and a mobilised volume of 1.15 Mm3. Despite its low velocity, the landslide regularly causes damage to a road and a water tunnel. For this reason, displacement and piezometry have been monitored since 2005. The monitoring system has been completed over time and a sufficiently complete geological profile has been drawn up. A key aspect in forecasting the mobility and risk of landslides is to obtain realistic soil strength parameters, in particular the angle of residual friction of the failure surface. Freixa (2021) performed a stability back-analysis using the limit equilibrium method, with a limited knowledge of the water flow in the landslide, and obtained a range of values for this angle between 27 and 31°. The main objective of this work has been to deepen the knowledge of the behaviour of the landslide. To this end, the longer auscultation record and samples from new boreholes have been used. Various laboratory tests have been carried out to characterise the material of the rupture surface; in particular, annular and direct shear tests to determine the residual friction angle. Values of 14-15º were obtained with the annular test and 35º with the direct test, using different fractions of the material. The core of this work has been the modelling of the water flow in the landslide and the stability of the landslide. The flow pattern observed in the field is indeed complex, and is considerably affected by the geometry and low permeability of the material of the failure surface (or band), by several large water surges and by the water tunnel through the landslide. El deslizamiento de El Forn de Canillo es uno de los deslizamientos más grandes del Pirineo con un volumen movilizado de 360 Mm3. El deslizamiento es inactivo en su gran parte, salvo en dos zonas. En una de ellas se ha centrado este trabajo; se trata del deslizamiento o lóbulo de Cal Ponet -Cal Borronet, con una velocidad media de entre 2-4 cm por año y con un volumen movilizado de 1,15 Mm3. A pesar de su pequeña velocidad, el deslizamiento causa regularmente daños a una carretera y a un túnel. Por este motivo, el desplazamiento y la piezometría se han monitorizado desde el año 2005. El sistema de auscultación se ha ido completando con el tiempo y se ha podido trazar un perfil geológico suficientemente completo. Un aspecto clave en la previsión de la movilidad y del riesgo del deslizamiento es obtener los parámetros resistentes del terreno de forma realista, en particular, del ángulo de fricción residual. Freixa (2021) realizó un análisis retrospectivo mediante el método de equilibrio límite, con un conocimiento limitado del flujo de agua en el deslizamiento, y obtuvo un rango de valores de este ángulo entre 27 y 31°. El objetivo esencial de este trabajo ha sido profundizar en el conocimiento del comportamiento del deslizamiento. Para ello, se ha aprovechado el registro más largo de la auscultación, y de muestras de nuevos sondeos. Se han realizado diversos ensayos de laboratorio para caracterizar el material de la superficie de rotura; en particular, ensayos de corte anular y directo para determinar el ángulo de fricción residual. Se obtuvieron valores de 14-15º, con el corte anular, y de 35º con el corte directo, utilizando diferentes fracciones del material. El núcleo de este trabajo ha sido la modelación del flujo de agua en el deslizamiento y de la estabilidad del deslizamiento.

Los acuíferos costeros se distinguen por su singular interacción tierra-mar y la principal dificultad para estudiar estos sistemas es la complejidad de sus ciclos biogeoquímicos. Los procesos importantes en la "zona de mezcla" de los acuíferos costeros controlan el suministro y el intercambio de compuestos químicos a las aguas subterráneas y, por lo tanto, son clave para comprender los flujos de solutos suministrados por las aguas subterráneas al mar y sus impactos en los ecosistemas costeros. Este cuerpo costero conocido como “estuario subterráneo” (STE), se caracteriza por su conexión hidráulica con el mar, creando una interfaz entre el agua dulce y el agua de mar. La distribución y composición de las sustancias que fluyen de la tierra al mar cambia porque las transformaciones que se producen en el acuífero están muy influenciadas por las descargas submarinas de aguas subterráneas y por el agua salada que ha invadido el acuífero a través de la conexión con el mar. Para estudiar estos procesos, se construyó un sitio de investigación en un área de 100m de largo tierra adentro desde la línea de costa y 30m de ancho, en el acuífero aluvial de Argentona, Mataró, al noreste de Barcelona, Cataluña (España). Este sitio experimental se estableció en 2014 y ha sido equipado para el monitoreo intensivo de procesos de acuíferos costeros como la intrusión marina (SWI) y las descargas submarinas de aguas subterráneas (SGD). Actualmente se monitorea con 25 piezómetros (2 metros apantallados) distribuidos en 5 nidos de 4 piezómetros cada uno (a intervalos de 10m, 20m, 15m y 25m) y 4 piezómetros individuales. En este sistema descrito como “sistema multiacuífero y reactivo”, se caracterizaron las condiciones fisicoquímicas, microbiológicas e hidrogeoquímicas asociadas a procesos biogeoquímicos a diferentes profundidades. Para este enfoque se presentarán los nuevos resultados relacionados con una campaña de monitoreo en diciembre de 2021 que caracterizan el estuario subterráneo. Coastal aquifers are distinguished by their unique land-sea interaction and the main difficulty in studying these systems is the complexity of their biogeochemical cycles. Important processes in the “mixing zone” of coastal aquifers control the supply and exchange of chemical compounds to groundwaters, and thus are key to understand the fluxes of solutes supplied by groundwater to the coastal sea and their impacts for coastal ecosystems. This coastal body known as a “subterranean estuary” (STE), is characterized by its hydraulic connection to the sea, creating an interface between freshwater and seawater. The distribution and composition of substances flowing from land to sea change because transformations that take place in the aquifer are highly influenced by the submarine groundwater discharges and the seawater that has invaded the aquifer through the connection to the sea. In order to study these processes, a research site was constructed in an area 100 m long inland from the coastline and 30 m wide, in the alluvial aquifer of Argentona, Mataró, northeast of Barcelona, Catalonia (Spain). This experimental site was established in 2014 and has been equipped for intensive monitoring of coastal aquifer processes such as Seawater Intrusion (SWI) and Submarine Groundwater Discharge (SGD). Currently, it is monitored with 25 piezometers (2 meters screened) distributed in 5 nests with 4 piezometers each (at 10m, 20m, 15m, and 25m intervals) and 4 individual piezometers. In this system described as a "multi-aquifer and reactive system", the physicochemical, microbiological and hydrogeochemical conditions associated with biogeochemical processes at different depths were characterized. For this approach, the new results related with a monitoring campaign in December 2021 that characterize the subterranean estuary will be presented.

The mechanical response of natural soils is characterized by a narrow elastic domain, a smooth transition between elastic to elasto-plastic regime, and hysteretic behaviour during cyclic loading. These realistic features can be efficiently intro-duced into an existing constitutive model by reformulating it in the framework of subloading surface plasticity. This unconven-tional elasto-plastic approach is advantageous over other techniques, since it allows to retain some stress history information only by adding an additional constitutive parameter and one hardening rule. In this paper, CASM, a state parameter dependent, critical state model, is reformulated in the framework of subloading plasticity. Several element tests are reported to illustrate the performance of the model.

This is the peer reviewed version of the following article: [Castañar, I, Codina, R, Baiges, J. A stabilized mixed three-field formulation for stress accurate analysis including the incompressible limit in finite strain solid dynamics. Int J Numer Methods Eng. 2023; 1- 26. doi: 10.1002/nme.7213], which has been published in final form at https://doi.org/10.1002/nme.7213. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. In this work a new methodology for finite strain solid dynamics problems for stress accurate analysis including the incompressible limit is presented. In previous works, the authors have presented the stabilized mixed displacement/pressure formulation to deal with the incompressibility constraint in finite strain solid dynamics. To this end, the momentum equation is complemented with a constitutive law for the pressure which emerges from the deviatoric/volumetric decomposition of the strain energy function for any hyperelastic material model. The incompressible limit is attained automatically depending on the material bulk modulus. This work exploits the concept of mixed methods to formulate stable displacement/pressure/deviatoric stress finite elements. The final goal is to design a finite element technology able to tackle simultaneously problems which may involve incompressible behavior together with a high degree of accuracy of the stress field. The variational multi-scale stabilization technique and, in particular, the orthogonal subgrid scale method allows the use of equal-order interpolations. These stabilization procedures lead to discrete problems which are fully stable, free of volumetric locking, stress oscillations and pressure fluctuations. Numerical benchmarks show that the results obtained compare very favorably with those obtained with the corresponding stabilized mixed displacement/pressure formulation.

The paper presents an iterative procedure for the time domain deconvolution in nonlinear elastoplastic materials. The approach is intended for the generation of input motions for dynamic soil–structure interaction (DSSI) numerical analyses when the desired earthquake is specified at the surface of a nonlinear soil deposit. The main advantage is that the same constitutive model (or models) to be used in the DSSI simulation to characterise the soil deposit is also employed in the deconvolution procedure. Therefore, the desired surface motion is recovered from the free-field propagation of the resulting input motion at the base of the numerical model, accounting for the assumed constitutive behaviour of the ground. An application example is also presented, where the potential of the proposed approach is shown.

Dynamic Cone Penetration Test (CPTu) profile offshore sediments by impact penetration. To exploit their results in full, the measured data are converted to obtain a quasi-static equivalent profile. Dynamic CPTu conversion requires calibrated correction models. Calibration is currently done by using paired (i.e., very close) quasi-static and dynamic tests. It is shown here that paired test data, which may be inconvenient to acquire offshore, are not strictly necessary to convert dynamic CPTu data. A new probabilistic methodology is proposed to call upon quasi-static results from a much wider area in the conversion procedure. Those results feed the prior distribution of a converted profile, within a Bayesian updating scheme where strain-rate coefficient and correction model error are also described by updated stochastic variables. The updating scheme is solved numerically using the Transitional Markov Chain Monte Carlo sampling algorithm. To avoid undue influence of local profile heterogeneity, the statistic treatment of the quasi-static CPTu data takes place in the frequency domain, using a discrete cosine transform. The new procedure is applied to a CPTu campaign offshore Nice (France): dynamic tests are converted with equal precision using quasi-static data acquired at distances orders of magnitude larger than what was previously employed.

Actualment, els murs de sòl reforçats són construccions extensament utilitzades en el camp de l'enginyeria geotècnica. Degut al seu bon comportament, la senzillesa en quan la construcció del conjunt i la avantatja econòmica en certes zones geogràfiques, fa que cada dia s’estudiï més en detall tots els elements que conformen els murs de sòl reforçat amb la finalitat d’optimitzar la tècnica. Aquestes estructures, es caracteritzen bàsicament de reforços embeguts en un terraplè que, connectats a un parament de formigó armat, generen una estabilitat de conjunt que permet guanyar grans alçades verticals. Es de vital importància analitzar en detall la interacció del sòl-reforç per definir les dimensions correctes de l’estructura. Mitjançant la realització d’assajos d’extracció de reforços s’ha pogut valorar en detall la interacció que generen diferents reforços amb el sòl granular i s’ha quantificat la resistència a l’arrencament que ofereixen cada un d’ells depenent de la seva naturalesa i geometria. Tot aquests assajos han estat realitzats sota condicions controlades al laboratori i els resultats han estat comparats amb dues normes internacionals. Actualmente, los muros de suelo reforzados son construcciones extensamente utilizadas en el campo de la ingeniería geotécnica. Debido a su buen comportamiento, la sencillez en cuando la construcción del conjunto y la aventaja económica en ciertas zonas geográficas, hace que cada día se estudie más en detalle todos los elementos que conformen los muros de suelo reforzado con el fin de optimizar la técnica. Estas estructures, se caracterizan básicamente de refuerzos embebidos en un terraplén que, conectados a una cara de hormigón armado, generan una estabilidad de conjunto que permite ganar grandes alturas verticales. Es de vital importancia analizar en detalle la interacción del suelo-refuerzo para definir los dimensiones correctas de la estructura. Mediante la realización de ensayos de extracción de refuerzos se ha podido valorar en detalle la interacción que generan diferentes refuerzos con el suelo granular y se ha cuantificado la resistencia al arrancamiento que ofrecen cada uno de ellos dependiendo de su naturaleza y geometría. Todo estos ensayos han sido realizados bajo condiciones controladas en el laboratorio y los resultados han sido comparados con dos normas internacionales. Nowadays, reinforced earth walls are extensively used in the field of geotechnical engineering. Due to its good behaviour, simplicity in building and the whole and economic advantage in certain geographical areas, makes it more interesting to study all the elements that make up the reinforced floor walls in order to optimise the technique. These structures are characterized primarily by reinforcements embedded in a embankment which, connected to a concrete wall, generate a set of stability that allows large vertical heights to be won. It is vitally important to analyse in detail the interaction of soil-reforcing to define the correct dimensions of the structure. By performing tests of extraction of reinforcements, it has been possible to assess in detail the interaction that generate different reinforcements with the granular soil and quantify the drag they offer each depending on their nature and geometry. All these tests have been carried out under laboratory-controlled conditions and the results have been compared with two international standards.

In the last two decades, both the amount and quality of geoinformation in the geosciences field have improved substantially due to the increasingly more widespread use of techniques such as Laser Scanning (LiDAR), digital photogrammetry, unmanned aerial vehicles, geophysical reconnaissance (seismic, electrical, geomagnetic), and ground-penetrating radar (GPR), among others. Furthermore, the advances in computing, storage and visualization resources allow the acquisition of 3D terrain models (surface and underground) with unprecedented ease and versatility. However, despite these scientific and technical developments, it is still a common practice to simplify the 3D data in 2D static images, losing part of its communicative potential. The objective of this paper is to demonstrate the possibilities of extended reality (XR) for communication and sharing of 3D geoinformation in the field of geosciences. A brief review of the different variants within XR is followed by the presentation of the design and functionalities of headset-type mixed-reality (MR) devices, which allow the 3D models to be investigated collaboratively by several users in the office environment. The specific focus is on the functionalities of Microsoft’s HoloLens 2 untethered holographic head mounted display (HMD), and the ADA Platform App by Clirio, which is used to manage model viewing with the HMD. We demonstrate the capabilities of MR for the visualization and dissemination of complex 3D information in geosciences in data rich and self-directed immersive environment, through selected 3D models (most of them of the Montserrat massif). Finally, we highlight the educational possibilities of MR technology. Today MR has an incipient and reduced use; we hope that it will gain popularity as the barriers of entry become lower. This research was funded by MCIN/ AEI/10.13039/501100011033: PID2019-103974RB-I00 and by Interreg V-A, POCTEFA: EFA364/19.

Els moviments de vessant són processos comuns en zones muntanyoses i representen un important perill per a infraestructures i zones edificades. Els impactes d'incendis forestals a l'estabilitat de vessants són múltiples i poc estudiats. Aquest estudi analitza l'estabilitat de vessants afectats per incendis mitjançant diferents mètodes ia dues escales (local i regional). La zona destudi serà el Berguedà. Los movimientos de ladera son procesos comunes en zonas montañosas y representan un importante peligro para infraestructuras y zonas edificadas. Los impactos de incendios forestales en la estabilidad de laderas son múltiples y poco estudiados. El presente estudio analiza la estabilidad de laderas afectada por incendios mediante diferentes métodos y a dos escalas (local y regional). La zona de estudio será el Berguedà. Slope movements are common processes in mountainous areas and represent a significant danger to infrastructure and built-up areas. The impacts of forest fires on the stability of slopes are multiple and little studied. The present study analyzes the stability of slopes affected by fires through different methods and at two scales (local and regional). The study area will be Berguedà.

Accurate estimates of soil unit weight are fundamental for correctly post process CPTu data and making use of Soil Behavior Type-based classification systems. Soil-specific and global regressions have been proposed for this purpose. However, soil-specific correlation might pose a problem of pertinence when applied at new sites. On the other hand, global correlations are easy to apply, but generally carry large systematic uncertainties. In this context, this work proposes a data clustering technique applied to geotechnical database aiming to identify hidden linear trends among dimensionless soil unit weight and normalized CPTu parameter according to some unobservable soil classes. Global correlations are then revisited according to such data subdivision aiming to improve accuracy of soil unit weight prediction while reducing transformation uncertainty. A new probabilistic criterion for soil unit weight prediction is also obtained. The potential benefits of the proposed procedure are illustrated with data from a Llobregat delta site (Spain).

The possibilities of the particle finite element method (PFEM) for modeling geotechnical problems are increasingly evident. PFEM is a numerical approach to solve large displacement and large strain continuum problems that are beyond the capabilities of classical finite element method (FEM). In PFEM, the computational domain is reconfigured for optimal solution by frequent remeshing and boundary updating. PFEM inherits many concepts, such as a Lagrangian description of continuum, from classic geomechanical FEM. This familiarity with more popular numerical methods facilitates learning and application. This work focuses on G-PFEM, a code specifically developed for the use of PFEM in geotechnical problems. The article has two purposes. The first is to give the reader an overview of the capabilities and main features of the current version of the G-PFEM and the second is to illustrate some of the newer developments of the code. G-PFEM can solve coupled hydro-mechanical static and dynamic problems involving the interaction of solid and/or deformable bodies. Realistic constitutive models for geomaterials are available, including features, such as structure and destructuration, which result in brittle response. The solutions are robust, solidly underpinned by numerical technology including mixed-field formulations, robust and mesh-independent integration of elastoplastic constitutive models and a rigorous and flexible treatment of contact interactions. The novel features presented in this work include the contact domain technique, a natural way to capture contact interactions and impose contact constraints between different continuum bodies, as well as a new simplified formulation for dynamic impact problems. The code performance is showcased by the simulation of several soil-structure interaction problems selected to highlight the novel code features: a rigid footing insertion in soft rock, pipeline insertion and subsequent lateral displacement on over-consolidated clay, screw-pile pull-out and the dynamic impact of a free-falling spherical penetrometer into clay. The authors acknowledge financial support by Severo Ochoa Centre of Excellence (2019–2023) Grant No. CEX2018-000797-S funded by MCIN/AEI/10.13039/501100011033 and research projects BIA2017-84752-R and PID2020-119598RB-I00.

Case studies and numerical simulations show that the long-term stability of tailings dams largely depends on the evolution of their water content. Therefore, desiccation is one of the critical processes influencing the tailing dam's safety. In this work, the air-drying of tailings, starting from a sludge condition, is studied using a fully instrumented column experiment, performed in an environmental chamber with temperature and relative humidity control. Based on the experimental observations, a conceptual model for the desiccation process is proposed. The model consists of the combination of two mechanisms driven by evaporation: shrinkage and capillary rise. The latter is only activated after a granular structure develops (shielding skeleton), capable of sustaining the suction-induced intergranular forces. This evidence explains the tendency of real deposits to develop an unsaturated, dry tailings crust enclosing a body of mud-consistency tailings. In addition, the role of dissolved salts in the desiccation process was observed. Solutes in pore water limit the evaporation rate throughout the test by increasing osmotic suction. Moreover, salt precipitation was observed to cause an interruption of the desiccation process on two occasions during the experiment: first, by the formation of a superficial precipitation crust and later by pore clogging within a shallow layer. The authors would like to thank Cristóbal García for the knowledge provided on the Cartagena - La Unión mining region, and the research team of the Geological and Mining Institute of Spain for their collaboration in the collection of tailings samples at the San Cristóbal mine. We would also like to thank the staff of the Soil Mechanics Laboratory of the Department of Civil and Environmental Engineering, Polytechnic University of Catalonia, Spain. Finally, we would like to thank the European Commission (CORDIS) through the project FP7-PEOPLE-IRSES-2008, Marie Curie Action "GEO-engineering EXChanges between Europe and Latin-America" for the financial collaboration in this work.

The impact of the use of sand treated with Colloidal Silica (CS) on a model 80 m high-earthfill dam was assessed through numerical modelling. The hydro-mechanical properties of the CS-Treated soil were taken from a previous laboratory study. Different strategies of treatment placement were studied, with increasing volumetric fractions of the dam being replaced by the treated material. Staged construction of the earthwork was simulated to evaluate the horizontal and vertical displacements at critical points within the dam. Different kinematics have been observed, depending on the quantities of CS-Treated material included in the soil structure. Moreover, the use of the treated soil was beneficial in terms of water outflow and upstream slope stability, in correspondence with different water reservoir levels. Different strategic patterns of CS-Treated sand placement are proposed herein to fully exploit the storage capacity of the dam, optimizing its stability. © 2022 American Society of Civil Engineers (ASCE). All rights reserved.

Proyecto que combina excavaciones en tierras y roca con estabilizaciones variadas (muros anclados, micropilotes, taludes en roca...) así como la interacción de la estructura de la edificación con la estabilidad del terreno. Project that combines excavations on land and rock with varied stabilizations (anchored walls, micropilots, rock slopes...) as well as the interaction of the structure of the building with the stabilization of the terrain. Projecte que combina excavacions en terres i roca amb estabilitzacions variades (murs ancorats, micropilots, talussos en roca...) així com la interacció de l'estructura de l'edificació amb l'estabilitat del terreny.

The use of stress–deformation analyses to evaluate the characteristics of possible static liquefaction events is rapidly becoming the norm for tailings dams exposed to such risk. Ideally, those analyses should be based on constitutive models that incorporate the fundamental mechanics of the problem, are able to perform robustly in commercial numerical platforms and are simple to calibrate. A model that aims to fulfil that specification is proposed. The model is a new implementation of a previously proposed model based on critical state concepts that is able to represent static liquefaction. The model formulation is elaborated to show that all the required inputs can be related to familiar concepts such as the critical state line, the state parameter, the normalised undrained peak strength or the coefficient of earth pressure at rest. The methodology is illustrated by analysing the failure of the Merriespruit tailings dam, which occurred in South Africa in 1994 and was instrumental in the recognition of how widespread liquefaction risk might be in saturated tailings. Numerical analysis of the case showed how a large static liquefaction failure might have been triggered by a relatively small slope erosion caused by overtopping.

Flow liquefaction is a geotechnical hazard in mine tailings storage facilities. Susceptibility to liquefaction is typically evaluated with the CPTu by estimating the state parameter (¿). This parameter allows estimating the contractive or dilative behaviour combining density and stress level under critical state soil mechanics (CSSM) framework. Soils with soil behaviour index (Ic) less than 2.60 and contractive behaviour are more susceptible to trigger liquefaction. Contractive/dilative behaviour can be also evaluated by alternative approaches, such as yield-stress-ratio (YSR). YSR values under a threshold value also given by CSSM indicate a contractive behaviour, while values above indicate dilative behaviour. This paper addresses the interpretation of CPTu data from a Brazilian mine tailings dams, categorising their states in terms of contractive/dilative behaviour to assess the liquefaction susceptibility of these complex materials. Although the two procedures applied have similar basis, the results obtained have similar basis, but the results obtained were not always coincident. The reasons for that are discussed in this paper, highlighting the justifications for such differences.

The presence of potentially liquefiable deposits in tailing dams represents a serious hazard, as is now increasingly clear that liquefaction triggering may occur in unanticipated ways. For legacy dams in which this hazard is already present, intervention alternatives are sought to mitigate the associated risks of liquefaction failure. One interesting possibility is to use targeted ground improvements of tailings within the structural zone of the dams, so that they become nonliquefiable. Liquefaction remediation technologies that are relatively gentle would be preferable, as the possibility of triggering liquefaction during the ground improvement operation itself cannot be lightly discarded. Permeation grouting is a classical soil improvement technology that has been renovated with the apparition of new permeating agents, such as colloidal silica suspensions (CS). Permeation grouting of CS consists in low-pressure injections leading to CS treated soils characterized by a significantly reduced liquefaction potential. CS grout has a complex rheology that is best described by a Bingham model whose parameters change in time. This paper presents design tools that incorporate this complexity and allow both a safer and more realistic design of permeation treatments. As an application example, we study a case based on the Merriespruit tailing dam, which failed by static liquefaction. It is concluded that CS permeation could realistically offer a potential solution to reduce instability risk of some tailing storage facilities (TSF).

Soil-facing mechanical interactions play an important role in the behavior of earth-retaining walls. Generally, numerical analysis of earth-retaining structures requires the use of interface elements between dissimilar component materials to model soil–structure interactions and to capture the transfer of normal and shear stresses through these discontinuities. In finite element method software programs, soil–structure interactions can be modeled using “zero-thickness” interface elements between the soil and structural components. These elements use a strength/stiffness reduction factor that is applied to the soil adjacent to the interface. However, in some numerical codes where the zero-thickness elements (or other similar special interface elements) are not available, the use of continuum elements to model soil–structure interactions is the only option. The continuum element approach allows more control of the interface features (i.e., material strength and stiffness properties), as well as the element sizes and shapes at the interfaces. This article proposes parameter values for zero-thickness elements that will give the same numerical outcomes as those using continuum elements in finite element and finite difference commercial software. The numerical results show good agreement for the computed loads transferred from soil to structure using both methods (i.e., zero-thickness elements and continuum elements at interfaces). Both different interface modeling approaches can give very similar results using equivalent interface property values and demonstrate the influence of choice of numerical mesh size on the numerical outcomes when continuum elements are used at the interfaces.

This paper illustrates how pressuremeter testing may add value to geotechnical characterization of tailing storage facilities (TSF). This is done with reference to results obtained in a campaign on jarosa, a lime-stabilized filtered jarosite residue that results from electrolytic zinc production. These residues are often stabilized chemically to minimize environmental con- cerns. The resulting stabilized product is disposed of by stacking in large deposits. Geomechanical characterization of the resulting stabilized residue, which is necessary for safe evaluation of the deposit mechanical stability, is more complex than that of other TSF, because of the presence of bonding and partial saturation. Pre-bored PMT results help to understand better the results from CPTu classification, offer good estimates of the at rest coefficient of earth pressure K0 and allow to calibrate CPTu for "in situ" identification of yield stress, a key design parameter in TSF storing filtered and/or bonded materials.

The geo-science and engineering fields have critical roles to play towards a sustainable energy future. This state-of-the-art review focusses on five areas where the geotechnical community has been involved the most: the oil and gas sector with emphasis on methane hydrates, carbon geological storage, geothermal, energy geo-storage, and nuclear waste storage. Extensive tables in the appendix identify potential geotechnical contributions to all energy resources (mining is critically needed to supply raw materials for the energy sector, yet is not addressed in this review). Energy-related applications involve a wide range of time and length scales, coupled thermo-hydro-chemo-mechanical processes, multi-phase fluids, high pressure-temperature-stress conditions, fines migration, reactive fluid transport and phase transformations, and multi-physics repetitive loads. Analysis and design require careful experimentation (including field-scale studies) and advanced numerical simulations. Educational programs must address the knowledge needs in energy geo-engineering.

En Enero de 2019 en Brumadinho (Brasil) una presa de relaves mineros de gran tamaño colapsó en su totalidad de forma brusca, causando la muerte a 270 personas y una gran conmoción en la minería mundial. La rotura fue capturada en video por una cámara que permitió identificar rápidamente el modo de rotura como uno de licuación. La cuestión pendiente era saber cómo se había desencadenado la licuación en este caso, pues los desencadenantes más habituales de este fenómeno como el sis-mo, la lluvia o las actividades de construcción brillaban por su ausencia. En este artículo se presentan brevemente los ensayos y análisis numéricos que se han llevado a cabo para responder tal pregunta en el marco de una investigación encargada por la Fis-calía (Ministerio Público Federal) de Brasil.

Failures due to static liquefaction have been too frequent in tailings dams. Stress-deformation numerical analyses based on critical state theory are able to reproduce those failures and may be used to gain insight into the different factors involved. One factor that is sometimes believed to play a role in liquefaction triggering is tailings creep, i.e. rate effects intrinsic to the tailings material. These timedependent effects are here explored using a constitutive viscoplastic model, referred to as CASMvisco. Effects on viscous parameters, stress level, and raising history on undrained creep are explored using simulated triaxial compression tests. The effect of creep-enabled consolidation is illustrated by the numerical simulation of a dam failure triggered by slope erosion.

Arguably, critical state soil mechanics (CSSM) is now the preeminent methodology for understanding static liquefaction of mine tailings, having been used in the mining industry by the expert panels retained to investigate recent TSF failures. One of the key ingredients of the CSSM framework is the assessment of a critical state line, which separates contractive from dila-tive states. A critical state line is often defined by a linear relationship and two parameters, namely the altitude of the critical state line at 1 kPa (¿) and its slope (¿). In this study, we use the TAILENG mine tailings database to investigate potential relationships between the particle fea-tures and the particle size distribution and the critical state properties. Towards this end, the crit-ical state line is evaluated for a range of mine tailings with broad gradations and compressibility, defining ¿and ¿, with known particle size distributions. This information is subsequently used to investigate potential correlations. Insights from the observations are shared, and potential funda-mental mechanisms in explaining correlations between the critical state properties and particle features are discussed.

Two case histories involving harbour works in a deltaic environment are described in the paper. The mechanisms underlying delta formation and development are outlined first; they involve climate changes, geological processes and human effects. The history of the Llobregat delta, the location of the case histories, is presented. The first case concerns the design and construction of a vertical caisson breakwater. The incorporation of storm wave loading, the description of the geological setting and the bases for stability evaluation are discussed. Special attention is given to the stability of the structure during the construction period when stability issues are more critical. The use of the envisaged observational method was hampered by the limited monitoring data available resulting in a modification of the planned approach. The second case refers to the reconstruction of the Prat quay after a major failure caused by the flow liquefaction of the hydraulically-deposited backfill. Post-failure investigation and analyses identified the need for reducing the liquefaction potential of the backfill and enhancing the undrained shear strength of the foundation clay; preloading was the main ground improvement method selected. The observational method was used to steer the construction activities to ensure an adequate margin of safety. The paper closes with some general considerations of the role of geology, observational method and judgement in the cases reported.

La revolución experimentada por el uso creciente de la geoinformación 3D en la ingeniería geológica, gracias a los avances tecnológicos, que progresivamente han facilitado una disponibilidad de técnicas de adquisición de datos y de herramientas para su análisis. Junto a los avances experimentados en la disponibilidad de recursos de computación y almacenamiento en la nube, han impulsado la expansión de numerosas aplicaciones que permiten la difusión de la geoinformación 3D en la web. A pesar de estos avances científico-técnicos, es común ver los datos 3D simplificados en imágenes estáticas 2D, perdiendo parte su potencialidad comunicativa. El objetivo de esta comunicación es presentar el diseño y las funcionalidades de unos visores web 3D de código abierto como una herramienta de sencilla utilización con la que interactuar y visualizar los resultados. Así mismo, estamos ensayando las posibilidades de la realidad mixta como una experiencia plenamente inmersiva para lograr una mejor comunicación de la geoinformación 3D.

Els despreniments són fenòmens que es donen amb freqüència i posen en risc, tant a les persones com la infraestructura. Un dels factors que l'ocasionen són els cicles de gel-desgel que es donen a les zones de muntanya. El present treball realitza un estudi sobre diferents condicionants perquè es doni lloc un cicle i que, per conseqüència, ocasionen esllavissades de terra. El treball es centra a la comarca de Berguedà, on s'utilitzen dues metodologies diferents per realitzar l'estudi. D'una banda, s'obtenen dades de punts de mesura per observar les oscil·lacions de temperatura i d'altra banda s'utilitzen Sistemes d'Informació Geogràfica (SIG) per a la projecció de les variables i generar un model que permeti mesurar la susceptibilitat de la zona a què es doni un cicle de gel-desgel. Los deslizamientos son fenómenos que se dan con frecuencia y ponen en riesgo, tanto a las personas como a infraestructura. Uno de los factores que lo ocasionan son los ciclos de hielo-deshielo que se dan en las zonas de montaña. El presente trabajo realiza un estudio sobre diferentes condicionantes para que se dé lugar un ciclo y que, por consecuencia, ocasionen deslizamientos de tierra. El trabajo se centra en la comarca del Berguedà, donde se utilizan dos metodologías diferentes para realizar el estudio. Por un lado, se obtiene datos de puntos de medida para observar las oscilaciones de temperatura y por otro lado se utilizan Sistemas de Información Geográfica (SIG) para la proyección de las variables y generar un modelo que permita medir la susceptibilidad de la zona a que se dé un ciclo de hielo-deshielo. Landslides are a natural process that occurs frequently and put both people and infrastructure at risk. One of the factors that cause it are the freezing cycles that occur in mountain areas. The present work carries out a study on different condition factors for a cycle to take place and, consequently, causes landslides. The study focuses on the Berguedà region, where two different methodologies are used to carry out the study. On the one hand, data are obtained from measurement points to observe temperature fluctuations and, on the other hand, Geographic Information Systems (GIS) are used to project the variables and generate a model that allows the susceptibility of the area where a freezing cycle occurs.

La zona comercial i d'oficines de barri Albereda és actual i tradicional, situat a la localitat de Sata Fe (Bogotà, Colòmbia) i el nucli està conformat pel centre tradicional de la ciutat. Santa Fe inclou la zona dels edificis governamentals i corporatius de la cursa Setena i de el Centre Internacional, el sector bancari de l'avinguda Jiménez, així com el tradicional barri comercial de Sant Victorino, que és un dels eixos de el comerç de Bogotà. A més, el sector també compta amb algunes de les principals universitats de país. El disseny de el projecte constructiu d'un pàrquing subterrani a la zona té com a objectiu estructurar un projecte que garanteixi a la població que labora, estudia, realitza turisme o intercanvis comercials esporàdics a la zona, un augment en l'oferta de places de parking, brindant comoditat i seguretat a l'hora de la disposició dels seus vehicles particulars. El projecte desenvolupat compta amb estàndards legals, arquitectònics i d'enginyeria acords a normes nacionals colombianes. La zona comercial y de oficinas del barrio Alameda es actual y tradicional, ubicado en la localidad de Sata Fé (Bogotá, Colombia) y cuyo núcleo esta conformado por el centro tradicional de la ciudad. Santa Fe incluye la zona de los edificios gubernamentales y corporativos de la carrera Séptima y del Centro Internacional, el sector bancario de la avenida Jiménez, así como el tradicional barrio comercial de San Victorino, que es uno de los ejes del comercio bogotano. Además, el sector también cuenta con algunas de las principales universidades del país. El diseño del proyecto constructivo de un parking subterráneo en la zona tiene como objetivo estructurar un proyecto que garantice a la población que labora, estudia, realiza turismo o intercambios comerciales esporádicos en la zona, un aumento en la oferta de plazas de parking, brindando comodidad y seguridad al momento de la disposición de sus vehículos particulares. El proyecto desarrollado cuenta con estándares legales, arquitectonicos y de ingeniería acordes a normas nacionales colombianas. The commercial and office area of ​​the Alameda neighborhood is current and traditional, located in the town of Sata Fé (Bogotá, Colombia) and whose core is made up of the traditional center of the city. Santa Fe includes the area of ​​government and corporate buildings on Carrera Séptima and Centro Internacional, the banking sector on Avenida Jiménez, as well as the traditional commercial district of San Victorino, which is one of the hubs of Bogotá's commerce. In addition, the sector also has some of the main universities in the country. The design of the construction project of an underground parking in the area aims to structure a project that guarantees the population that works, studies, carries out tourism or sporadic commercial exchanges in the area, an increase in the supply of parking spaces, providing comfort and security when disposing of their private vehicles. The developed project has legal, architectural and engineering standards in accordance with Colombian national standards.

Los depósitos de relaves presentan características geotécnicas que los hacen susceptibles de sufrir falla por licuefacción, por lo que las implicaciones de riesgo de este rasgo sólo se han apreciado en su totalidad recientemente. Por ello, es de interés actual estudiar las posibles técnicas de remediación de los depósitos existentes, centrándose en las posibilidades de tratamiento de los relaves mediante inyecciones por permeación. La tesis comienza presentando una visión general de los métodos de manejo de residuos y de las propiedades geotécnicas de los depósitos. Además, se presta especial atención a la permeabilidad mediante la ecuación propuesta por Chapuis y Aubertin (2003) y evaluada a partir de una base de datos de propiedades de relaves proporcionada por el Instituto Geológico y Minero de España. En consecuencia, se recalibra la ecuación original y se verifica utilizando los valores de permeabilidad de otros estudios publicados. A continuación, se revisan los posibles métodos de tratamiento del terreno adaptados a los relaves, divididos en tres grandes categorías: densificación, consolidación y tratamientos químicos. A continuación, se determina que el método de inyección por permeación es el más adecuado. A través de la evaluación de dos productos de sílice coloidal MP320 y MP325, aplicadas a un caso basado en la presa de Merriespruit, se obtienen los resultados de factor de seguridad, tiempos de ejecución y costo total de operación. A partir de los resultados obtenidos, se puede abrir la puerta a futuros estudios aplicados a la remediación de depósitos de relaves mediante tratamiento de inyección por permeación Tailing deposits present geotechnical characteristics which make them susceptible to liquefaction flow failure, hence the risk implications of this trait have only been recently appreciated in full. It is therefore of current interest to study possible remediation techniques for existing deposits. This dissertation contributes to this end by focusing on the possibilities of tailing treatment by permeation of cementing agents. The thesis starts by presenting an overview of tailing disposal methods and geotechnical properties of tailing deposits. Furthermore, special attention is paid to permeability by examining the equations proposed by Chapuis and Aubertin (2003) and evaluated using a database of tailings properties provided by the Geology and Mine Institute of Spain. Consequently, the original equation is recalibrated and then verified using permeability values from other published studies. Possible ground treatment methods for tailings are then reviewed in three broad categories: densification, consolidation, and chemical treatments. It is then determined that permeation grouting method is the best adapted. Pre-design and evaluation of ground improvement treatment for a tailing dam are then carried on for two colloidal silica products (MP320 and MP325) in a case comparable to the Merriespruit tailing dam, which failed by overtopping-induced liquefaction. Through the evaluation of two colloidal silica products MP320 and MP325, applied to a case based on the Merriespruit dam, the safety factor results are then obtained and so the time and cost of operation. From these obtained results, a new door can be opened to future studies applied to the remediation of tailings deposits by permeation injection treatments. Els dipòsits de relaves presenten característiques geotècniques que els fan susceptibles de patir falla per liqüefacció, de manera que les implicacions de risc d'aquest tret només s'han apreciat en la seva totalitat recentment. Per això, és d'interès actual estudiar les possibles tècniques de remediació dels dipòsits existents, centrant-se en les possibilitats de tractament dels relaves mitjançant injeccions per permeació. La tesi comença presentant una visió general dels mètodes de maneig de residus i de les propietats geotècniques dels dipòsits. A més, es presta especial atenció a la permeabilitat mitjançant l'equació proposada per Chapuis i Aubertin (2003) i avaluada a partir d'una base de dades de propietats de relaves proporcionada per l'Institut Geològic i Miner d'Espanya. En conseqüència, es recalibra l'equació original i es verifica utilitzant els valors de permeabilitat d'altres estudis publicats. A continuació, es revisen els possibles mètodes de tractament del terreny adaptats als relaves, dividits en tres grans categories: densificació, consolidació i tractaments químics. A continuació, es determina que el mètode d'injecció per permeació és el més adequat. A través de l'avaluació de dos productes de sílice col·loïdal MP320 i MP325, aplicades a un cas basat en la presa de Merriespruit, s'obtenen els resultats de factor de seguretat, temps d'execució i cost total d'operació. A partir dels resultats obtinguts, es pot obrir la porta a futurs estudis aplicats a la remediació de dipòsits de relaves mitjançant tractament d'injecció per permeació.

La construcción es un sector mundialmente conocido y que engloba en su interior una gran cantidad de pequeños campos que, en ocasiones, no son tan conocidos. Este es el caso de la geotecnia, estudio previo a cualquier construcción que debiera ser obligatorio en todos los casos. Inherente a la construcción existen sus riesgos laborales y, por lo tanto, sus cursos formativos de prevención. El problema detectado en este trabajo es la poca especialización de estos cursos formativos, en concreto, en los trabajos de geotecnia debido a la falta de material específico. Detectada esta carencia, en este trabajo se plantea y desarrolla la posibilidad de creación de contenido formativo complementario avanzado tecnológicamente en forma de simulación virtual. Para ello se sigue un proceso de diseño bajo criterios como el realismo y la formación, entre otros. Después se crean los elementos necesarios para la simulación con el programa de diseño y modelado Sketchup 3d. Posteriormente a través del motor de creación de videojuegos Unity 3d se crean las diversas interacciones entre el usuario de la simulación y los elementos creados. Con estas interacciones se logran representar algunos de los accidentes más comunes sufridos en la geotecnia. Finalmente se presenta la simulación terminada y se evalúan los resultados obtenidos, así como futuras líneas de desarrollo. Construction is a world-renowned sector that encompasses a large number of small fields that are sometimes not so well known. This is the case of geotechnical engineering, a study previous to any construction that should be required in all cases. Associated with construction are its work risks and, therefore, its prevention training courses. The problem detected in this work is the low specialization of these training courses, specifically in geotechnical works due to the low level of specific material. Having detected this problem, this work proposes and develops the possibility of creating technologically advanced complementary training content in the format of virtual simulation. For this purpose, a design process is followed under requirements such as realism and training, among others. Then the necessary elements for the simulation are created with the design and modeling program Sketchup 3d. Then, through the Unity 3D video game creation engine, the various interactions between the user of the simulation and the created elements are created. With these interactions it is possible to represent some of the most common accidents suffered in geotechnical engineering. Finally, the finished simulation is presented and the results obtained are evaluated, as well as future lines of development.

La susceptibilitat d'esllavissades pot ser interpretada com una tendència d'una regió a generar esllavissades (Guzzetti et al., 2006). Atès que aquests fenòmens a escala regional poden ser desencadenats per diversos factors usualment no disponibles a aquesta magnitud. Es comú emprar-se en les anàlisis d'esllavissades en models digitals d'elevació i, en alguns casos, amb base a la informació d'usos del terreny i mapes geològics (Palau et al., 2020). L'objectiu principal d'aquest estudi és estimar la probabilitat de ruptura a escala regional en base a dades georeferenciades i generar un mapa de susceptibilitat de lliscament tenint com a unitats de terreny, les unitats hidrològiques. D'altra banda, es proposen i s'avaluen diversos criteris d'agrupació de les classes de susceptibilitat. Es van generar mapes de conques i mitjanes conques hidrogràfiques tenint com a dada d'entrada el model digital d'elevació amb diferents valors de nombre mínim de píxels. Aquest paràmetre es va mostrar molt important, vist que afecta a les àrees dels polígons en la seva distribució, en el mapa i en la seva morfologia. Es van estudiar cinc possibles valors de nombre mínim de píxels iguals a 1 milió, 750, 500, 250 i 100 mil. Els resultats van mostrar que es té una distribució més equitativa d'àrees amb les conques amb menors espais mínims. Es van estudiar vuit criteris d'agrupació: tres criteris estadístics i cinc criteris proposats en aquest estudi denominats de "A" a "I". El criteri "C" va proporcionar el resultat més satisfactori. La susceptibilidad de deslizamientos puede ser interpretada como una tendencia de una región en generar deslizamientos (Guzzetti et al., 2006). Dado que estos fenómenos a escala regional pueden ser desencadenados por varios factores usualmente no disponibles a esta magnitud, es común emplearse en los análisis de deslizamientos modelos digitales de elevación y, en algunos casos con base en la información de usos del terreno y mapas geológicos (Palau et al., 2020). El objetivo principal de este estudio es estimar la probabilidad de rotura a escala regional con base en datos georreferenciados y generar un mapa de susceptibilidad de deslizamiento teniendo como unidades de terreno, las unidades hidrológicas. Por otra parte, se proponen y evalúan diversos criterios de agrupación de las clases de susceptibilidad. Se generaron mapas de cuencas y medias cuencas hidrográficas teniendo como dato de entrada el modelo digital de elevación con diferentes valores de número mínimo de pixeles. Este parámetro se mostró de suma importancia, visto que afecta las áreas de los polígonos, su distribución en el mapa y su morfología. Se estudiaron cinco posibles valores de número mínimo de pixeles iguales a 1 millón, 750, 500, 250 y 100 mil. Los resultados mostraron que se tiene una distribución más equitativa de áreas con las cuencas con menores tamaños mínimos. Se estudiaron ocho criterios de agrupación: tres criterios estadísticos y otros cinco criterios propuestos en este estudio denominados de “A” a “E”. El criterio “C” proporcionó el resultado más satisfactorio. The susceptibility to landslides can be interpreted as a tendency of a region to generate landslides (Guzzetti et al., 2006). Given that these phenomena on a regional scale can be triggered by various factors usually not available at this magnitude, it is common to use digital elevation models in landslide analysis and, in some cases, based on information from land use and geological maps (Palau et al., 2020). The main objective of this study is to estimate the probability of failure on a regional scale based on georeferenced data and to generate a landslide susceptibility map having hydrological units as terrain units. On the other hand, various criteria for grouping the susceptibility classes are proposed and evaluated. Basins and half basins maps were generated with the digital elevation model as input data with different values of the minimum number of pixels. This parameter was very important, since it affects the areas of the polygons, their distribution on the map and their morphology. Five possible values of the minimum number of pixels equal to 1 million, 750, 500, 250 and 100 thousand were studied. The results showed that there is a more equitable distribution of areas with the basins with smaller minimum sizes. Eight grouping criteria were studied: three statistical and another five criteria proposed in this study called “A” to “E”. Criterion "C" provided the most satisfactory result.

Landslides are the most widespread geological event. They can cause big amounts of deaths as well as economic losses. There are several processes of monitoring, although the visual inspection in the early stages of the movements should be enhanced. On the other hand, the construction industry is at the edge of digitalisation and emergent technologies are being developed and implemented, such as Augmented Reality, BIM and 3D printing. This thesis, hence, aims to propose an Augmented Reality app with the objective of enhancing visual geotechnical on-site inspections in order to make them more effective and mitigate future risks.

The knowledge of the marine subsoil is a fundamental fact for the correct development of a modern and sustainable dredging project. An accurate defnition of all geological deposits and their dredgeability is directly related to a realistic cost estimation and to the employment of the most efcient equipment. In this sense the combination of geophysical and geotechnical techniques allows optimizing marine investigation surveys and obtaining more precise subsoil models in terms of morphology and dredgeability properties of the diferent units involved. The experience in this kind of projects in diferent sea conditions and a widely range of soil/rock has allowed defning the most appropriate research techniques as well as the suitable equipment and the necessary type of vessel. This paper also presents some brief results of a geophysical and geotechnical marine investigation carried out in the Port of Langosteira (A Coruña, Spain) for dredging works in a rocky seabed.

El riesgo de catástrofes producidas por terremotos supone un factor relevante en el diseño estructural para zonas de elevada intensidad y frecuencia sísmica. Debido a esto, se han desarrollado diversas tecnologías orientadas a mejorar el comportamiento sísmico de las estructuras civiles. En el presente trabajo se ha analizado el comportamiento sísmico de puentes de luces continúas considerando disipadores de energía de bajo costo. Se ha hecho especial énfasis en el análisis de la pila central, la cual sirve como apoyo de continuidad para este tipo de estructuras. Específicamente, se ha analizado el comportamiento de pilas altas, las cuales suelen verse afectadas por efectos de segundo orden (P-Delta) cuando suceden sacudidas del suelo producidas por terremotos. Dentro de los dispositivos de protección sísmica que existen actualmente se encuentran los disipadores Shear Link Bozzo (SLB). Estos dispositivos de bajo costo han sido utilizados con cierta frecuencia en el diseño de edificios sismo-resistentes. Por tal razón, su uso en puentes continuos marca una innovadora propuesta, principalmente en zonas de sismicidad moderada-a- alta. Entre los resultados principales, se destaca que la sección transversal de la pila central puede reducirse considerablemente si se tiene en cuenta la contribución del dispositivo de disipación de energía. Este hecho tiene importantes consecuencias económicas, particularmente en zonas de difícil acceso donde las pilas altas resultan necesarias en la planificación de viaductos de gran longitud. La caracterización de la amenaza sísmica y el modelado de la estructura se han llevado a cabo de manera exhaustiva. La respuesta sísmica se ha obtenido haciendo uso del análisis dinámico no lineal. En términos de amenaza sísmica, se han obtenido registros reales de bases de datos europeas, los cuales son compatibles con el espectro de diseño propuesto por el Eurocódigo 8 para zonas de amenaza tipo 1; el tipo de suelo se ha supuesto como roca competente. Respecto al modelo realizado, el puente ha sido caracterizado mediante el clásico enfoque de emparrillado plano. Para esto, se ha desarrollado un modelo de elementos finitos tipo barra dentro de un programa de cálculo frecuentemente usado para este tipo de estructuras. Se han considerado los posibles efectos no lineales debido a la plastificación de los elementos estructurales y la geometría. Los resultados obtenidos muestran una considerable reducción de los esfuerzos inducidos a la estructura debido a los casos de carga sísmica considerados, tanto en el momento flector como en el cortante en la base de la pila. Además, se ha encontrado que estos dispositivos reducen el desplazamiento en la parte superior de la pila, lo cual tiene un impacto directo en los efectos P- Delta. Aunque aún preliminares, los resultados obtenidos son prometedores y abren una futura línea de investigación en el cálculo de puentes en zonas sísmicas. Finalmente, se presentan valores aproximados enfocados a cuantificar el ahorro potencial de materiales y coste total de la estructura al usar dispositivos SLB. Cabe también mencionar que la búsqueda de elementos estructurales óptimos no sólo tiene consecuencias económicas sino también medioambientales. En otras palabras, reducir el uso de materiales como el hormigón tiene impacto directo sobre la huella de carbono generada por estructuras civiles que usan este material. El risc de catàstrofes produïdes per terratrèmols suposa un factor rellevant en el disseny estructural per a zones d'elevada intensitat i freqüència sísmica. A causa d'això, s'han desenvolupat diverses tecnologies orientades a millorar el comportament sísmic de les estructures civils. En el present treball s'ha analitzat el comportament sísmic de ponts de llums continues considerant dissipadors d'energia de baix cost. S'ha fet especial èmfasi en l'anàlisi de la pila central, la qual serveix com a suport de continuïtat per a aquesta mena d'estructures. Específicament, s'ha analitzat el comportament de piles altes, les quals solen veure's afectades per efectes de segon ordre (P-Delta) quan succeeixen sacsejades del sòl produïdes per terratrèmols. Dins dels dispositius de protecció sísmica que existeixen actualment es troben els dissipadors Shear Link Bozzo (SLB). Aquests dispositius de baix cost han estat utilitzats amb una certa freqüència en el disseny d'edificis sisme-resistents. Per tal raó, el seu ús en ponts continus marca una innovadora proposta, principalment en zones de sismicitat moderada-a-alta. Entre els resultats principals, es destaca que la secció transversal de la pila central pot reduir-se considerablement si es té en compte la contribució del dispositiu de dissipació d'energia. Aquest fet té importants conseqüències econòmiques, particularment en zones de difícil accés on les piles altes resulten necessàries en la planificació de viaductes de gran longitud. La caracterització de l'amenaça sísmica i el modelatge de l'estructura s'han dut a terme de manera exhaustiva. La resposta sísmica s'ha obtingut fent ús de l'anàlisi dinàmica no lineal. En termes d'amenaça sísmica, s'han obtingut registres reals de bases de dades europees, els quals són compatibles amb l'espectre de disseny proposat pel Eurocodi 8 per a zones d'amenaça tipus 1; el tipus de sòl s'ha suposat com a roca competent. Respecte al model realitzat, el pont ha estat caracteritzat mitjançant el clàssic enfocament d'engraellat pla. Per a això, s'ha desenvolupat un model d'elements finits tipus escombri dins d'un programa de càlcul sovint usat per a aquesta mena d'estructures. S'han considerat els possibles efectes no lineals a causa de la plastificació dels elements estructurals i la geometria. Els resultats obtinguts mostren una considerable reducció dels esforços induïts a l'estructura a causa dels casos de càrrega sísmica considerats, tant en el moment flector com en el tallant en la base de la pila. A més, s'ha trobat que aquests dispositius redueixen el desplaçament en la part superior de la pila, la qual cosa té un impacte directe en els efectes P-Delta. Si bé encara preliminars, els resultats obtinguts són prometedors i obren una futura línia de recerca en el càlcul de ponts en zones sísmiques. Finalment, es presenten valors aproximats enfocats a quantificar l'estalvi potencial de materials i cost total de l'estructura en usar dispositius SLB. Cap també esmentar que la cerca d'elements estructurals òptims no sols té conseqüències econòmiques sinó també mediambientals. En altres paraules, reduir l'ús de materials com el formigó té impacte directe sobre la petjada de carboni generada per estructures civils que usen aquest material. The risk of catastrophes produced by earthquakes is a relevant factor in the structural design for areas of high intensity and seismic frequency. Due to this, several technologies have been developed aimed at improving the seismic behavior of civil structures. In the present study, the seismic behavior of continuous-span bridges has been analyzed considering low-cost energy dissipators. Special emphasis has been placed on the analysis of the central pile, which serves as continuity support for this type of structure. Specifically, the behavior of high-rise piles has been analyzed, which are usually affected by second-order effects (P-Delta) when ground shaking occurs caused by earthquakes. Among the seismic protection devices that currently exist are the Shear Link Bozzo (SLB). These low-cost devices have been used with some frequency in the design of earthquake-resistant buildings. For this reason, its use in continuous bridges marks an innovative proposal, mainly in areas of moderate-to-high seismicity. Among the main results, it is highlighted that the cross section of the central pile can be considerably reduced if the contribution of the energy dissipation device is taken into account. This fact has important economic consequences, particularly in areas of difficult access where high piles are necessary in the planning of long viaducts. The characterization of the seismic hazard and the modelling of the structure have been carried out exhaustively. The seismic response has been obtained using non-linear dynamic analysis. In terms of seismic hazard, actual records have been obtained from European databases, which are compatible with the design spectrum proposed by Eurocode 8 for type 1 hazard zones; the soil type has been assumed as competent rock. Regarding the modeling, the bridge has been characterized by the classic flat grid approach. For this, a bar-type finite element model has been developed within a calculation program frequently used for this type of structure. Possible non-linear effects due to the plasticization of the structural elements and the geometry have been considered. The results obtained show a considerable reduction in the stresses induced to the structure due to the seismic load cases considered, both in the bending moment and in the shear at the base of the pier. In addition, these devices have been found to reduce the displacement at the top of the pile, which has a direct impact on P-Delta effects. Although still preliminary, the results obtained are promising and open a future line of research in the calculation of bridges in seismic zones. Finally, approximate values are presented focused on quantifying the potential savings in materials and total cost of the structure when using SLB devices. It is also worth mentioning that the search for optimal structural elements not only has economic but also environmental consequences. In other words, reducing the use of materials such as concrete has a direct impact on the carbon footprint generated by civil structures that use this material.

The architecture, engineering, construction and operations industry has high accident rates as a result of characteristics of the construction site and work activities, the heavy machinery used and a lack of safety culture. In particular, geotechnical drilling worksites involve the use of high-powered machinery and workers are exposed to different risks when using them. However, risk prevention training courses are not well-specialised for this type of work. There is a lack of adequate learning content specific to drilling works, meaning the heavy machinery, how to use it and how to prevent accidents due to these drilling tasks are poorly understood. Therefore, this research explores the potential of virtual reality technology as a tool for analysing the risks associated with geotechnical drilling works and as complementary training content to traditional courses. A specific use case, a geotechnical drilling machine is modelled in 3D and integrated into a realistic virtual reality environment where the movements of the machine are recreated, in addition to interactions so that workers can simulate the geotechnical drilling process, identify risks and prevent accidents, and, moreover, be trained in best practices for machinery usage, according to previous real-world experiences from senior workers. © 2021 WIT Press This work has been supported by the CONICYT through its economic support of Felipe Muñoz, beneficiary of a pre-doctoral grant (CONICYT – PCHA/International Doctorate/2019-72200306) and by the Ministry of Science, Innovation and Universities of Spain (MICIU) through the BIMIoTICa project (RTC-2017-6454-7). The authors also acknowledge financial support from the Spanish Ministry of Economy and Competitiveness, through the “Severo Ochoa Programme for Centres of Excellence in R&D (CEX2018-000797-S)”.

El despreniment de roques és una amenaça present en massissos dotats de forts pendents, on la identificació de la perillositat no és una tasca fàcil. Aquesta es defineix com la probabilitat d'ocurrència o la "freqüència" juntament relacionada amb la "magnitud" del fenomen o el seu potencial destructiu . En aquesta investigació, es presenta un enfocament alternatiu per a l'anàlisi de la perillositat de despreniments en base als inventaris d'esdeveniments, presentant una metodologia general que es posa a prova a l'àrea de Montserrat. Aquesta zona està situada a 50 km al nord-oest de Barcelona i és àmpliament coneguda per la seva importància patrimonial, natural i cultural. Per tal de quantificar el perill dels despreniments rocosos, s'ha efectuat un anàlisis de freqüència de magnitud a partir d'un inventari basat en esdeveniments recopilat de la vigilància de camp i investigació històrica. S’ha determinat una metodologia per optimitzar els 205 registres lliurats per l'Institut Cartogràfic i Geològic de Catalunya (ICGC), amb informació de volum i data. Per optimitzar l'anàlisi, s'ha dividit l'inventari en cinc submostres segons el nivell d'importància donat pel nombre de visitants i de dades registrades, anomenades: Coves de l'Salnitre, Cremallera, Carretera BP 1103, Monestir i el seu aparcament. Els resultats de l’anàlisis, en relació a la magnitud freqüència, han mostrat un ajust òptim seguint la llei potencial amb exponents que van des de -0,35 a -0,63 per magnituds entre 0,01 i 1000 m3. La metodologia desenvolupada ha retornat que per tota la muntanya, s’esperen 27 esdeveniments anuals per a un volum d'1 m3, atribuint un perill elevat si es té en compte l'alt nombre de visitants. Addicionalment, els resultats obtinguts s’han contrastat amb els resultats de la monitorització de les campanyes TLS (Terrestrial Laser Scanner), es van obtenir dades coherents, i fins i tot localment, un elevat grau d'ajust. La caída de rocas es una amenaza presente en macizos con fuertes pendientes, donde no es una tarea fácil poder identificar la peligrosidad, definida como la probabilidad de ocurrencia o la "frecuencia" relacionada con la "magnitud" del fenómeno o su potencial destructivo. En esta investigación, se presenta un enfoque para el análisis de la peligrosidad de desprendimientos en base a los inventarios de eventos presentando una metodología general, y se prueba en el área de Montserrat, Esta zona está ubicada a 50 km al noroeste de Barcelona y es conocida por su importancia patrimonial, natural y cultural. Para cuantificar la peligrosidad de desprendimientos de rocas, se ha realizado un análisis de magnitud y frecuencia a partir de un inventario de eventos recopilado de la vigilancia de campo y de la investigación histórica. Se ha determinado una metodología para analizar los 205 registros entregados por el Institut Cartogràfic i Geològic de Catalunya (ICGC). Para optimizar el análisis, se ha dividido el inventario en cinco submuestras según el nivel de importancia dado por el número de visitantes y de datos registrados, llamadas: Coves del Salnitre, Cremallera, Carretera BP 1103, Monasterio y su aparcamiento. Los resultados del análisis de la relación magnitud frecuencia mostraron ajustes óptimos por la ley potencial con exponentes que van desde -0,35 a -0,63 para magnitudes entre 0,01 y 1000 m3. Al aplicar la metodología desarrollada a todo Montserrat dio como resultado 27 eventos por año para un volumen igual o superior a 1 m3, lo cual es un peligro relevante, teniendo en consideración el alto número de visitantes. Adicionalmente, se contrastaron los resultados obtenidos con los resultantes de la monitorización con láser escáner terrestre (TLS), obteniendo datos coherentes, e incluso localmente, un elevado grado de ajuste. Rockfall is a threat present in massifs with steep slopes. It is not an easy task to quantify the hazard, defined as the probability of occurrence or the “frequency” related with the “magnitude” of the phenomenon or its destructive potential. This research presents an approach for hazard assessment of rockfalls based on inventory events presenting a general methodology, and it is tested in Montserrat area. This zone located 50 km northwest of Barcelona, it is well-known for its patrimonial, natural and cultural significance. In order to quantify the rockfall hazard, a magnitude and frequency analysis has been carried out, taking data from an event inventory compiled by field monitoring and historical research. A methodology was determined to analyze 205 records delivered by the Institut Cartogràfic i Geològic de Catalunya (ICGC). To optimize the analysis, the inventory has been divided into five subsamples according to the level of importance given by the number of visitors and registered data, called: Coves del Salnitre, Cremallera, Carretera BP 1103, Monastery and its parking. The analytical results of the magnitude frequency relationship presented an optimal fitting according to the power law, with exponents ranging from -0.35 to -0.63 for magnitudes between 0.01 and 1000 m3. Applying the developed methodology to all Monserrat, gives the result of 27 events are to be expected annually for a volume of 1 m3, which poses a significant threat considering the elevated number of visitors. Additionally, the results were contrasted with those obtained from the monitoring with a TLS (Terrestrial Laser Scanner), consistent data was obtained, and even a high degree of fitting was achieved locally.

Copyright ASTM International. All rights reserved, 2018/16/07. Downloaded by UPC, pursuant to Author/Copyright Owner Agreement. No further reproduction authorized. Calibration chambers are frequently used to verify, adapt, or both verify and adapt empirical relations between different state variables and in situ test results. Virtual calibration chambers (VCC) built with 3D discrete element models may be used to extend and partially substitute costly physical testing series. VCC are used here to explore the mechanics of flat dilatometer penetration and expansion. Results obtained for a simulation of physical tests in Ticino sand are presented. Blade tip resistance during penetration is in good agreement with the experiments. A piston-like design is used for the blade so that larger displacements may be applied than it is possible with a membrane. Initial piston pressures in the expansion curves are very low, strongly affected by the scaled-up grain sizes. Despite that difficulty, expansion curves may be easily interpreted to recover dilatometer moduli ED close to those observed in the physical experiments. Particle-scale examination of the results allows a firmer understanding of the current limitations and future potential of the technique.

The final publication is available at Springer via http://dx.doi.org/10.1007/s40999-018-0314-z A zoned earth dam 40 m high is analysed and modelled using a numerical code able to deal with unsaturated–saturated soils and the coupled hydro-mechanical phenomena. The paper discusses the selection of the materials for the design of the dam. The dam construction was modelled at the design stage (a type “A” calculation) and results are compared with actual measurements registered during construction until the time when the dam reached two-thirds of the total final height. The limitations of the type A model are discussed and an updated model is presented taking into account compaction data and field tests performed during construction. The first author acknowledges the financial support to CIMNE by the CERCA Programme/Generalitat de Catalunya and the fellowship IJCI-2015-26342 from the Spanish government.

Life cycle assessment (LCA) is recognised as a powerful technique to determine the environmental impact component of sustainability assessments of structures in civil engineering projects at the time of design. This paper explains the principal parts and stages in an LCA methodology and demonstrates the approach using the examples of two conventional retaining wall types (gravity and cantilever type) and two mechanically stabilised earth (MSE) wall solutions using steel and polymeric soil reinforcement. The analyses include structures built to four different heights. The LCA methodology was able to quantitatively distinguish between the component environmental impacts of different wall solutions and thus provide a practical numerical score-based tool for designers to choose between candidate solutions. The MSE wall solutions resulted in lower environmental impacts than gravity and cantilever wall solutions as measured by global warming potential, cumulative energy demand, six major midpoint environmental indicator categories, three endpoint damage categories and in terms of overall endpoint scores. The target audiences for this paper are geotechnical and structural engineers engaged in the design of earth retaining wall structures but are less familiar with recent developments in LCA and how LCA can be linked to the design of these systems.

In civil engineering, mining and the petroleum industry in-situ stress state knowledge is fundamental. To estimate the stress state in-situ methods are applied, these methods are not sufficient to fully estimate the stress field in 3D due to the sparsity of observations and the paucity of stress measurements. In the current master’s thesis, a framework is developed through Reduced-Order Models (ROM) to predict the vertical displacement field, and consequently the stress state, when variations in the material and geometric properties of the problem are introduced. To achieve this, four different methods are tested in four different examples, one of them with uncertainty in the properties of the material and the last three with geometric uncertainties. The four methods tested are Artificial Neural Network with Levenberg Marquardt training algorithm (LM), Artificial Neural Network with Gradi-ent Descent with Momentum training algorithm (GDM), Proper Orthogonal Decom-position (POD) and Encapsulated Proper Generalized Decomposition (Encapsulated PGD) The developed framework consists of three parts. First, the data generator module creates a series of samples through Latin Hypercube Sampling varying the geometric or material properties of the problem and then obtains the vertical displacement field by the Finite Element Method (FEM) simulations. The second module applies any of the four methods to build a reduced-order model and finally, the third module is applied, if necessary, to reconstruct the vertical displacement field. Outgoing

It has recently been shown (Arroyo et al. [1]) that 3D DEM models are able to reproduce with reasonable accuracy the macroscopic response of CPT performed in calibration chambers filled with sand. However, the cost of each simulation is an important factor. Hence, to achieve manageable simulation times the discrete material representing the sand was scaled up to sizes that were more typical of gravel than sand. A side effect of the scaled-up discrete material size employed in the model was an increased fluctuation of the macro-response that can be filtered away to observe a macroscopic steady-state cone resistance. That observation is the starting point of this communication, where a series of simulations in which the size ratio between penetrometer and particles is varied are systematically analyzed. A micromechanical analysis of the penetrometer–particle interaction is performed. These curves reveal that a steady state is arrived also at the particle–cone contact level. The properties of this dynamic interface are independent of the initial density of the granular material.

The paper describes the failure of Aznalcóllar dam, in southern Spain, in April 1998. The rockfill dam slid forward and released a flow of acid-saturated tailings. The geology and geomorphology of the site are described. The results of a detailed laboratory testing programme on the tailings material and on the overconsolidated high-plasticity foundation clay are given. Special attention is paid to the identification of cementation of the tailings and to the strength and consolidation properties of the foundation clay. Failure features are interpreted on the basis of the field evidence, taking into account the measured geotechnical properties of the materials involved.

El present treball consisteix en la presentació d’un mètode de modelització geològica 3D amb el software Vulcan de la zona de Manresa per a, posteriorment, proposar dues seccions de túnel ferroviari amb capacitat per a dos vagons de metro al subsòl de la pròpia ciutat. Les dades de les que es parteix són les dades públiques disponibles a la web de ICGC. D’aquestes dades s’han utilitzat principalment tots els sondejos disponibles a la zona d’estudi, un total 374 incloent cales i penetròmetres. A part s’ha fet ús de la cartografia geològica 1:25000 del full corresponent a Manresa, de la cartografia geològica 1:50000 del Bages i de la base topogràfica municipal 1:5000. Per a la modelització del subsòl s’han tractat individualment cada un dels sondejos per a generar una base de dades dividida en tres taules, per a això s’han decidit quins són els horitzons que s’han volgut representar que seran els que contindran la línia de metro. En aquest cas els horitzons modelitzats han estat els corresponents als terciaris marins i continentals, als quaternaris que s’han dipositat a sobre i, per últim, els reblons antròpics i vegetals que es troben per sobre tant dels sòls quaternaris com dels massissos terciaris. Donada la poca representativitat de les dades de partida, el present treball s’ha continuat amb dades obtingudes de la literatura consultada i plasmada a la bibliografia ja que no s’aconsegueix un model fiable amb les dades públiques disponibles. Posteriorment es proposen dues seccions per a la línia de metro, una de circular per a extreure amb tuneladora i una altra per a l’extracció amb mètodes convencionals seguint el Nou Mètode Austríac i el mètode Belga. Per a les simulacions geotècniques del massís contenidor del túnel s’han utilitzat els softwares RocData, per a les propietats del massís rocós; Examine2D, per a comprovar esforços a les parets del túnel i possibles trencaments; Dips, per al càlcul de despreniments al interior del túnel per cunyes i RocSupport, per al càlcul dels sosteniments de la secció circular. Finalment, seguint la normativa actual en matèria de túnels ferroviaris, es decanta per a la construcció de la línia de metro seguint el Nou Mètode Austríac per als massissos quaternaris marins i continentals i el mètode Belga per a poder travessar el terreny fallat que es troba al sud-est de Manresa. The present work paper consists in the presentation of a 3D geological modelling with Vulcan software in the Manresa’s zone for, later, propose two rail tunnel sections with enough capacity for two subway wagons in the subsoil of the city. The starting data is the public data available at the web page of ICGC. Of this data it has been used mainly all the drill holes available at the studied area, a total of 374 including manual drill holes and penetrometers. Apart it has been used the geological cartography 1:25000 of the Manresa’s sheet, the geological cartography 1:50000 of Bages and the municipal topographical base 1:5000. For the modelling of the subsalt each drill hole has been treated individually in order to generate a database divided in four spreadsheets, to do so it has been decided which are the horizons that are wanted to be represented and which are the containers of the subway line. In that case the modelled horizons are the ones corresponding with the marine and continental tertiaries, the quaternaries that has been deposed on their top and, finally the anthropic and vegetation rivets that can be found above the tertiary masses and quaternary soils. Due the poor representativeness of the starting data, the present work paper has been continued with the data obtained from the consulted literature available at the bibliography since a reliable model has not been achieved with the public data available. Later two subway lines are proposed, one circular to be extracted with a tunnelling machine and another one to be extracted with conventional methods following the New Austrian Method and the Belgic method. For the geotechnical simulations of the container mass of the tunnels the RockData software has been used; Examine2D, to check the stresses in the tunnel walls and its breaks; Dips, to compute the landslides inside the tunnel for wedges and RocSupport, for the calculation of the supports of the circular section. Finally, following the current standards on rail tunnels, it prefers to build the subway line following the New Austrian Method for the marine and continental quaternary massifs and the Belgian method to cross the failed terrain that is in the south- east of Manresa.

to appear; International audience; Strain localization zones in the form of shear bands or compaction bands in geomaterials are observed across scales from sub-millimetric (grain size) to kilometric scale (geological structures). Triggering and evolution of such narrow zones of localized deformation depends on many factors. The mechanical behavior of geomaterials is central for the formation of such zones. However, thermal, pore-pressure and chemical effects play a crucial role in shear and compaction banding. Temperature increase and activation of chemical reactions such as mineral dehydration, carbonate decomposition, as well as dissolution/precipitation control the triggering and the evolution of localized deformation zones. Moreover, the inherent heterogeneous microstructure of geomaterials plays a significant role during strain localization. The purpose of this paper is to provide a review of recent research regarding the effects of temperature, pore-pressure, chemical reactions and microstructure on strain localization in geomaterials. Examples have been taken in relation with seismic slip and with compaction banding. Strain localization is treated as an instability from a homogeneous deformation state. Different types of instabilities may (co-) exist depending on different multi-physical couplings and micro-mechanisms. Finally, a comparison of rate dependent Cauchy continuum and rate independent generalized continua (Cosserat continuum) is made, which leads to an analog expression for the critical perturbation wave length, which scales the thickness of the localized zone and defines the region that non-homogeneous deformations are possible.

Within the context of deep geological radioactive waste disposal, the French National Radioactive Waste Management Agency (Andra) is conducting a research program including in-situ experiments at the Meuse/Haute-Marne Underground Research Laboratory (MHM URL), which aims to demonstrate the feasibility of constructing and operating a High Level Waste (HLW) disposal facility in the Callovo-Oxfordian (COx) claystone formation and to improve it. ALC1604 experiment is an in-situ heating test reproducing a full-scale HLW disposal cell. Heating devices were placed in the last 15 m of a 25 m long steel cased micro-tunnel to mimic the heat emitted by the HLW packages. The present experiment allows to study the response of the cell and the surrounding rock under thermal loading. More specifically, this experiment studied the thermo-mechanical (TM) behavior of the steel sleeve, equipped with strain gauges, displacement sensors, temperature sensors, etc., and monitored the evolution of the annular space (the gap between the sleeve and the rock). It also studied the thermo-hydro-mechanical (THM) behavior of the near/far field rock through pore pressure and temperature measurements installed in peripheral boreholes. The TM response of the steel sleeve and the THM response of the surrounding rock are numerically reproduced and the chosen THM parameters are compared with previous small-scale in-situ experiments conducted at the MHM URL in order to improve the reliability of the material parameters of the COx. The lessons learned from this experiment has provided valuable feedback towards implementing new full-scale heating experiments consistent with a new benchmark concept. DECOVALEX is an international research project comprising participants from industry, government and academia, focusing on development of understanding, models and codes in complex coupled problems in sub-surface geological and engineering applications; DECOVALEX-2019 is the current phase of the project. The authors appreciate and thank the DECOVALEX-2019 Funding Organizations Andra, BGR/UFZ, CNSC, US DOE, ENSI, JAEA, IRSN, KAERI, NWMO, RWM, SÚRAO, SSM and Taipower for their financial and technical support of the work described in this report. The statements made in the report are, however, solely those of the authors and do not necessarily reflect those of the Funding Organizations. The experimental work presented in this article has received funding from the European Atomic Energy Community's Seventh Framework Program under Grant Agreement n◦269905, the LUCOEX project. The financial support is gratefully acknowledged.

Ground Penetrating Radar (GPR) is a prospecting method frequently used in monitoring asphalt pavements, especially as an optimal complement to the defection test that is commonly used for determining the structural condition of the pavements. Its application is supported by studies that demonstrate the existence of a relationship between the parameters determined in GPR data (usually travel time and wave amplitude) and the preservation conditions of the structure. However, the analysis of frequencies is rarely applied in pavement assessment. Nevertheless, spectral analysis is widespread in other fields such as medicine or dynamic analysis, being one the most common analytical methods in wave processing through use of the Fourier transform. Nevertheless, spectral analysis has not been thoroughly applied and evaluated in GPR surveys, specifically in the field of pavement structures. This work is focused on analyzing the behavior of the GPR data spectra as a consequence of different problems affecting the pavement. The study focuses on the determination of areas with failures in bituminous pavement structures. Results epitomize the sensitivity of frequencies to the materials and, in some cases, to the damage. This research has been partially funded by the Spanish 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 study is also a contribution to the EU Action COST TU1208 “Civil Engineering Applications of Ground Penetrating Radar” financed by the European Union.

This paper shows how three new concepts – ‘Design Cases’ (introduced in prEN 1990), the ‘Geotechnical Design Model’ (prEN 1997-1), and the ‘Ground Model’ (prEN 1997-2) – are combined (in prEN 1997-3) to provide a comprehensive and flexible set of tools for the design of specific geotechnical structures. The paper presents flow charts divided between: a) reliability management, b) ground modelling, c) verification of the design, and d) structure execution, which provide guidelines for navigating prEN 1990 and prEN 1997.

This paper shows how three new concepts – ‘Design Cases’ (introduced in prEN 1990), the ‘Geotechnical Design Model’ (prEN 1997-1), and the ‘Ground Model’ (prEN 1997-2) – are combined (in prEN 1997-3) to provide a comprehensive and flexible set of tools for the design of specific geotechnical structures. The paper presents flow charts divided between: a) reliability management, b) ground modelling, c) verification of the design, and d) structure execution, which provide guidelines for navigating prEN 1990 and prEN 1997.

This paper describes the development of the final Project Team (PT) draft of the next generation of Eurocode 7 Part 1 (EN 1997-1:202x). The use of Nationally Determined Parameters and the drive for ease-of-use is highlighted. Key changes from the previous version of EN 1997-1 are explained, including the introduction of the Geotechnical Design Model; revision of the Geotechnical Categories and their application; the implementation of Consequence Classes and Geotechnical Complexity Classes in achieving the reliability required by the Eurocodes; elaboration on the use of numerical methods within Eurocode 7; the treatment of rock on an equal basis with soil; and greater emphasis on the Observational Method.

This paper presents an overview of the contents of Eurocode 7 Part 2, highlighting the major changes that are planned as its focus turns from test methods to the assessment of properties for engineering design. The motivation for this change and the anticipated type of information that will be given for each parameter is described. In addition the process for developing the ground model is discussed.