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Memòria del Departament 2012

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Cursos, conferències i seminaris

19/01/2012: Seminari d'Hidrologia Subterrània

AUTOR: Luis Cueto (Massachusetts Institute of Technology)
TÍTOL: Upscaled models of multiphase flow in porous media with partial wetting
DESCRIPCIÓ: I will present a theoretical framework to upscale multiphase flow through porous media, in the case of partially wetting systems. I focus on a simple application: describing two-phase flow in a capillary tube using aggregate macroscopic variables such as fluid saturations.
At static equilibrium, partial wetting leads to non-spreading, local structures (fluid slugs in our capillary tube). Out of equilibrium, partial wetting systems exhibit hysteresis and pseudo-dynamic behavior: for example, when water is displaced by air in a capillary tube, a thin water film is left attached to the tube walls, and the amount of fluid left behind increases with the injection rate. These features cannot be reproduced with second-order nonlinear advection-diffusion equations.
Our model captures these features, leading to non-spreading, compactly-supported solutions as steady-states of a scalar conservation law. Rate-dependent flow features arise naturally in our model as the competition between viscous and capillary forces. Finally, I will discuss the extension of these ideas to the macroscopic description of multiphase flow through more complex porous media.
LLOC: UPC-Campus Nord, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Planta Baixa, Aula CIHS

26/01/2012: Seminari d'Hidrologia Subterrània

AUTOR: M. Carmen Chaparro
TÍTOL: El Cabril: datos de instrumentación y modelación numérica de las celdas de almacenamiento de residuos radioactivos
DESCRIPCIÓ: El Cabril és la instal.lació d'emmagatzematge de residus radioactius de baixa i mitja activitat d'Espanya. Des de l'estiu de 2003 es recull aigua del desguàs d'algunes cel.les d'emmagatzematge, l'aigua recollida te una elevada concentració de triti. El Grup d'Hidrologia Subterrània de la UPC postulà una hipòtesi basada en el mecanisme de flux capi.llar i de vapor, que mitjançant models numèrics, explica la sortida de l'aigua del desguàs de les cel.les a partir de processos d'evaporació i condensació al formigó. Degut a aquests models es començaren a instrumentar les cel.les 1 i 16. Amb l'objectiu de verificar aquesta hipòtesi a partir de les dades obtingudes de la instrumentació de les cel.les i dels paràmetres hidràulics obtinguts a partir d'assaigs d'evaporació, es pretén realitzar un model de la cel.la més realista, utilitzant el codi CODE_BRIGHT.
LLOC: UPC, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Planta Baixa, Aula CIHS

05-09/03/2012: XIX Curs d'Explosius a les Obres Públiques

DESCRIPCIÓ: L' ús dels explosius industrials en determinades fases de la construcció de les obres públiques, o a la edificació, constitueix una eina irreemplaçable degut a la seva economia i eficàcia. En alguns casos, com per exemple excavacions i demolicions, les voladures són d'àmbit urbà.
Les tècniques modernes han arribat a nivells de definició que garanteixen l'eficàcia de l'ús d'explosius per aplicacions molt diverses.
El present curs s'organitza amb la intenció de dotar de coneixements adequats als enginyers (de grau o postgrau): tipus d'explosius, disseny i control de voladures, rendiments de l'excavació (granulometria dels blocs-qualitat del massís, etc.).
En definitiva es tracta d'un curs de tipus general enfocat al coneixement dels materials i termes tècnics relatius als explosius, i les seves aplicacions en el camp de l'Enginyeria Civil.
LLOC: UPC, Edifici C1, Sala de Tesines (002)

16/02/2012: Seminari d'Hidrologia Subterrània

AUTOR: Cristina Valhondo
TÍTOL: Degradación de los microcontaminantes orgánicos en la recarga artificial a través de una balsa de infiltración con barrera reactiva
DESCRIPCIÓ: La recarga artificial de acuíferos es una técnica de constatada utilidad en el ámbito de la gestión de los recursos hídricos (aumenta su cantidad y mejora su calidad). Se ha comprobado que algunos parámetros químicos del agua, tales como DBO, sólidos en suspensión, contenido en nitratos y sulfatos, mejoran durante la renaturalización de agua mediante el sistema de balsas de infiltración. Sin embargo, las aguas procedentes de plantas de tratamiento, o afectadas por ellas, presentan además otros tipos de contaminantes orgánicos. En particular, los contaminantes emergentes (productos farmacéuticos, drogas ilícitas, etc.) se encuentran en muy bajas concentraciones (ng/L), pero son potencialmente nocivos para los humanos y el medio acuático en general. Además, muchos de ellos no se eliminan completamente en las plantas de tratamiento con las tecnologías convencionales. Existen numerosos estudios que demuestran que la recarga artificial es eficiente en la eliminación de algunos de estos compuestos, principalmente debido a procesos de adsorción y biodegradación. Hay evidencias de que las condiciones redox dominantes pueden influir en el comportamiento de estos contaminantes en ensayos de laboratorio. Sin embargo, los datos sobre esta influencia en campo son más limitados Nuestra pregunta es, si es posible optimizar la eliminación de los micro-contaminantes emergentes mediante la colocación de una capa reactiva en el fondo de una balsa de infiltración para así aumentar la adsorción y favorecer una zonación redox en el acuífero. Se han realizado campañas durante los periodos de infiltración antes y después de la colocación de la capa reactiva, y también en periodos sin infiltración, con el objetivo de determinar variaciones en el comportamiento de los micro contaminantes orgánicos.
LLOC: UPC, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Aula CIHS (D2-001)

09/02/2012: Seminari d'Hidrologia Subterrània

AUTOR: Felipe de Barros
TÍTOL: Integrating health and hydrogeology: A multi-component methodology for decision making and uncertainty reduction
DESCRIPCIÓ: Obtaining accurate predictions of human health risks from groundwater contamination is a challenge. The main difficulty relies on the fact that many of the components that constitute a human health risk assessment are uncertain. Amongst these, we highlight two classes of parameters: (1) hydrogeological and (2) health-related. Usually, sampling strategies are developed with the goal of reducing uncertainty, but less often they are developed in the context of their impacts on uncertainty. Understanding the impact from each of these components in human health risk can provide guidance for decision makers to best allocate resources towards minimal prediction uncertainty. One of the key points in risk management consists of knowing where to invest characterization efforts in a cost-effective manner. In this talk, a multi-component health risk-based framework is presented which allows decision makers to set priorities through a visualization tool. Results highlight the role of characteristic length-scales characterizing flow and transport in determining data needs within an integrated hydrogeological-health framework. Finally, I will illustrate conditions where uncertainty reduction in human health risk may benefit from better understanding of the health component as opposed to a more detail hydrogeological characterization.
LLOC: UPC-Campus Nord, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Planta Baixa, Aula CIHS

23/02/2012: Seminari d'Hidrologia Subterrània

AUTOR: Simonetta Rubol
TÍTOL: Is soil moisture a good proxy to describe the aerobic/anaerobic status of soil and predict nitrous oxide emissions?
DESCRIPCIÓ: In this talk, I will address the interaction between biochemical and diffusive controls in unsaturated soils. It is well known that microbes react to environmental conditions on different time scales. When such environmental conditions are favorable to bacteria (e.g., rewetting, substrate amendment), the residing population exits the dormant state, becomes active and starts synthesizing extra-cellular enzymes. If substrate availability, and hence energy, is sufficient, microbes may begin to reproduce and increase in population size. These dynamics make it challenging to interpret measured relationships between microbial activity (e.g., respiration, denitrification, N mineralization) and environmental conditions. As a primary interest, I investigate the relationship between bacterial activity, soil moisture and soil oxygen levels under static and dynamics condition. Additionally, I present a lumped model that (i) accounts for biogeochemical and diffusive controls on trace gas sources and (ii) captures the competition between N-retention and N-loss pathways.
LLOC: UPC, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Aula CIHS (D2-001)

12/01/2012: Seminari d'Hidrologia Subterrània

AUTOR: Ilenia Battiato (Max Planck Institute for Dynamics and Self-Organization, Alemania y Clemson University, USA)
TÍTOL: Hybrid models of reactive transport in porous and fractured media
DESCRIPCIÓ: Darcy-scale models of flow and transport in porous media often fail to describe experimentally observed phenomena, while their pore-scale counterparts are accurate but can be computationally prohibitive. Most numerical multi-scale models, which seek to combine these two descriptions, require empirical closures and/or assumptions on the behavior of pore-scale quantities at the continuum (Darcy) scale. We present a general formulation of an iterative hybrid numerical method that links these two scales without resorting to such approximations. The algorithm treats the fluxes exchanged at the internal boundaries between the pore- and continuum-scale domains as unknown, and allows for iteratively determined boundary conditions to be applied at the pore-scale in order to guarantee their continuity. While the algorithm proposed is general, we use it to model Taylor dispersion in a fracture with chemically reactive walls. Results show significant improvement upon standard continuum-scale formulations.
LLOC: UPC, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Aula CIHS (D2-001)

01/03/2012: Seminari d'Hidrologia Subterrània

AUTOR: Jesús Carrera
TÍTOL: The ever increasing inversion challenge. Lessons from Mar del Plata
DESCRIPCIÓ: Inversion challenges increase over time because of increases on the volumen of data, and on model expectations and complexity. Here we review some of these challenges and reasonable responses. Specifically, we address the problems associated to: (1) Different types of data and parameters and how to properly weigh them, (2) handling highly frequently sampled time series; and (3) handling of spatial variability, which has been the most challenging issue during the last 30 years. Specifically, the problem remains how to blend geological understanding, which is conceptually rich, within stochastic inversion methodologies, which demand quantitative information. We illustrate some of these problems with the application to Mar del Plata aquifer, where data are available for nearly a century. Geologically based models, where spatial variability is handled through zonation, yield very similar results to geostatiscally based models. Here, similarity is meant both in the ability to fit observations and in the appearance of the final transmissivity fields. This finding suggests that, in cases where much less data are available, geologically based models may perform better than those purely based on geostatistics. In fact, when analyzing the traditional hydrogeological approach, it becomes apparent that hydrogeology is essentially multidisciplinary. The challenge we face is how to bring together the need for multidisciplinarity with the ever increasing complexity of each discipline.
LLOC: UPC, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Aula CIHS (D2-001)

08/03/2012: Seminari d'Hidrologia Subterrània

AUTOR: Lurdes Martínez
TÍTOL: Hydraulic tests to identify the CO2 saturation at a geological site
DESCRIPCIÓ: Hydraulic tests will be performed at Hontomin to derive local and regional transmissivity as well as connectivity patterns. In addition, CO2 push-pull tests will be performed to characterize dissolution kinetics and trapping efficiency. However, estimating the volume of CO2 trapped in the aquifer after the push-pull test is hard. We propose to use hydraulic tests to estimate this volume. Supercritical CO2 is quite compressible. Therefore, the storage coefficient of the aquifer with trapped CO2 should be much larger than that without. Another effect that should be expected is a decrease in permeability caused by trapped CO2 that blocks the largest pores.
These two effects can be measured by means of hydraulic testing. This would require carrying out different field campaigns before and after the injection of CO2 in order to be able to assess changes in the hydraulic parameters.
This work presents a synthetic modeling exercise where both the storage coefficient and hydraulic conductivity vary depending on the percentages of trapped CO2. Simulations have considered conditions similar to a real repository, i.e. 60°C temperature and 150 bars pressure. The results show that this technique is effective to detect and quantify the CO2 trapped in the aquifer.
LLOC: UPC, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Aula CIHS (D2-001)

15/03/2012: Seminari d'Hidrologia Subterrània

AUTOR: Bruno Cubillo
TÍTOL: Aplicación del ensayo térmico mediante sensores de temperatura de fibra óptica (DTS) para el almacenamiento geológico de CO2 en la Planta de Desarrollo Tecnológico de Hontomín
DESCRIPCIÓN: El ensayo térmico es uno de los métodos utilizados en el almacenamiento geológico de CO2 para determinar su presencia en las formaciones. En la Planta de Desarrollo Tecnológico de Hontomín (Burgos, España) se realizarán una batería de ensayos de caracterización. Dentro de este marco, el ensayo térmico tiene el objetivo de determinar la presencia de CO2, además de poder detectar fugas en el entorno del pozo. A lo largo del pozo se instrumentan cables eléctricos que producirán un gradiente térmico en el entorno del pozo y cables de fibra óptica DTS (Distributed Thermal Sensing) que realizaran medidas de temperatura cada metro con una precisión de 0,1ºC. Las perturbaciones térmicas generan diferentes respuestas del medio debido a las diferentes propiedades térmicas entre el CO2 y las aguas salobres presentes en la formación almacén. Utilizando la analogía formal entre el flujo hidráulico y la conducción de calor se realizan simulaciones numéricas. Utilizando la interpretación analítica de Jacob y apoyado en el análisis de los resultados mediante curvas de diagnóstico se estima que para determinar saturaciones residuales de CO2 serían necesarios ensayos con una duración larga.
LLOC: UPC, Dep. Enginyeria del Terreny, Cartogràfica i Geofísica, Mòdul D2, Aula CIHS (D2-001)

14/03/2012: XI Jornades de Enginyeria Geològica: Catàstrofes de l'Enginyeria del Terreny

DESCRIPCIÓ:

Por onzè any consecutiu, la Delegació d'Alumnes d'Enginyeria Geològica (DAEG), amb el suport de l'Escola Tècnica Superior d'Enginyers de Camins, Canals i Ports de Barcelona (ETSECCPB) i de la Facultat de Geologia de la UB, organitza les Jornades d'Enginyeria Geològica sota el títol: "Catàstrofes de l'Enginyeria del Terreny".

Aquest any les jornades d'enginyeria geològica pretenen introduir als estudiants a diversos problemes que poden ocórrer en el camp de l'enginyer geòleg.

Els estudis d'Enginyeria Geològica són uns estudis transversals amb molts camps d'actuació possibles, és per això que ens ha semblat molt important convidar a professionals que treballen en diferents entorns per explicar-nos aquestes adversitats.

Des de la DAEG agraïm la participació i l'esforç dels professors, ponents, estudiants i participants que fan possible aquesta nova edició de les Jornades d'Enginyeria Geològica.

LLOC: UPC-Campus Nord, Edif. C2, Sala d'Actes ETSECCPB

13-15/06/2012: Sort Course on CODE_BRIGHT

DESCRIPCIÓ: CODE_BRIGHT is a general-purpose finite element program developed by the Department of Geotechnical Engineering and Geosciences of the Universitat Politécnica de Catalunya (DIT-UPC) for the analysis of coupled thermo-hydro-mechanical (THM) phenomena in geological media.
The development of CODE_BRIGHT started in 1990 with the purpose of modelling the response of saline materials in the context of deep nuclear waste disposal. The initial capabilities were soon extended to include a wider range of geological materials and, in particular, unsaturated soils. General transport processes and their interaction with the material mechanical behaviour were added in order to develop a generalised tool for THM analysis.
CODE_BRIGHT has been extensively verified and validated in international benchmark exercises. It has been applied to the analysis of different geoenvironmental schemes and waste disposal designs. In the recent past many other relevant geotechnical problems involving saturated/ unsaturated flow and stress strain behaviour have been analysed with the help of CODE_BRIGHT. The course will provide an appropriate coverage of theoretical background, numerical aspects, details of problem solving and examples of application.
CODE_BRIGHT is backed by a detailed reference and Tutorial Manual, a description of the Theoretical Bases and a publication on Validation Exercises solved with the code. Course material includes the Theoretical Background and Validation documents as well as a copy of relevant publications.
LLOC: Edufucu D2, Aula 201

22/03/2012: Seminari d'Hidrologia Subterrània

AUTOR: Ana Trapote
TÍTOL: Efecte de l'aigua sobre la durabilitat del formigó per a l'emmagatzematge de residus radioactius
DESCRIPCIÓ: Des de l'estiu del 2003 s'ha estat recollint aigua en els sistemes de control d'infiltracions d'algunes cel.les d'El Cabril. L'aigua que passa a través del formigó, a més de dissoldre les fases que ho composen augmenta la porositat i, per tant, el grau de penetració. El resultat final és un procés de degradació del formigó que, en el cas dels residus radioactius de baixa i mitjana activitat, ha de mantenir les seves propietats barrera entre 300 i 400 anys. Degut a la impossibilitat de realitzar demostracions directes de la integritat dels contenidors de formigó a aquestes escales de temps, s'ha de realitzar una aproximació basada en assaigs curts de durabilitat i la seva extrapolació a llargs periodes de temps mitjançant modelació numèrica.
LLOC: Edifici D2, Aula CIHS

12/04/2012: Seminari d'Hidrologia Subterrània

AUTOR: Christopher Henri
TÍTOL: Modeling serial reaction using random walk particles tracking methods
DESCRIPCIÓ: DNAPL is, since the middle of the previous century, a clear identified problem for the management of urban and suburban groundwater resources quality. Random walk particles tracking methods showed their legitimacy and efficiency on the modeling of reactive transport especially thanks to the absence of numerical dispersion or their computational efficiency. We present here a new method to reproduce efficiently a serial reaction as the natural degradation of chlorinated solvents into a trustable 3-dimensions random walk particle-tracking model (RW3D). The chemical specie is defined as a particle property (state of the particle). Results of the zeroth spatial moment of the mass transfer equation derivation in the Fourier domain are used as particle state transition probabilities. We obtain thereby the state of a particle after a given time i.e. the mass evolution of the different species involved into the serial reaction. We apply this approach with the modeling of the chlorinated compounds resulting from the tetrachloroethylene (PCE) sequential degradation (PCE, TCE, DCE, VC). The particle tracking approach is successfully compared to the renowned finite difference code RT3D. Finally, this approach integrated into the stable lagrangian model RW3D represents a trustable and efficient alternative to model serial reaction in a complex environment.
LLOC: Edifici D2, Aula CIHS

19/04/2012: Seminari d'Hidrologia Subterrània

AUTOR: Marco Dentz
TÍTOL: Mixing in heterogeneous porous media
DESCRIPCIÓ: Observed chemical transport and reaction behaviors in heterogeneous media are quantitatively and qualitatively different from the ones expected for equivalent homogeneous media. Spatial fluctuations in the physical and chemical medium properties can lead to anomalous transport behaviors characterized by early or late solute arrivals, forward and backward tails of spatial solute distribution and enhanced spreading. Such behaviors can be linked to mass transfer processes over complex heterogeneity-induced interfaces and to the notion of incomplete mixing on the macroscopic support scale. Traditionally, the description of solute mixing in heterogeneous media was limited to effective dispersion coefficients, which, however, are not suited to characterize mixing state and mixing dynamics of a heterogeneous system. Mixing is related to concentration variability and thus can be measured in terms of concentration variance, suitable entropy measures, or in terms of the probability density function of concentration values. We present some approaches to quantify heterogeneityinduced solute mixing and discuss the mixing dynamics observed in moderately and highly heterogeneous porous media.
LLOC: Edifici D2, Aula CIHS

03/05/2012: 4th Workshop of CODE_BRIGHT users

DESCRIPCIÓ:  The Department of Geotechnical Engineering and Geosciences of the Technical University of Catalonia (UPC) is organising the Fourth workshop of CODE_BRIGHT users to be held on 3rd May, 2012.

CODE_BRIGHT is a general-purpose code for the 3-D analysis of coupled thermo-hydro-mechanical (THM) phenomena in geological media (including conservative transport of chemical species). Application fields cover geoenvironmental engineering (multi-barrier protection systems, radioactive waste disposal schemes, clay liners, two-phase liquid/gas flow, soil-atmosphere interaction) and geotechnical engineering (embankments, earthdams, expansive and collapsible soils, pavements, tunnels).

The workshop aims to bring together scientists and engineers with different backgrounds for two days of interaction to share experiences and promote joint initiatives. The workshop expects to cover topics such as,
  • standard applications
  • new developments in advanced applications
  • prospective developments
LLOC: Edifici B1, Aula 001A

03/05/2012: Seminari d'Hidrologia Subterrània

AUTOR: Anna Jurado
TÍTOL: Drugs of abuse in urban groundwater. A case study: Barcelona
DESCRIPCIÓ: This study is concerned with drugs of abuse (DAs) and their metabolites in urban groundwater at field scale in relation to (1) the spatial distribution of DAs in Barcelona’s groundwater, (2) the depth of the groundwater samples, (3) the presence of DAs in recharge sources, and (4) the assessment of the fate of DAs in Barcelona aquifers. To this end, 37 urban groundwater samples were collected in the city of Barcelona and a total of 21 drugs were analyzed including cocainics, amphetamine-like compounds, opioids, lysergics and cannabinoids and the prescribed drugs benzodiazepines. Overall, the highest groundwater concentrations (around 200 ng/L in SAP-4) and the largest number of detected DAs were found in zones basically recharged by a river that receives large amounts of effluents from waste water treatment plants (WWTPs). In contrast, the urbanized areas yielded not only lower concentrations but also a much smaller number of drugs, which suggests a local origin. In fact, cocaine and its metabolite were dominant in more prosperous neighbourhoods, whereas the cheaper MDMA was the dominant DA in middle-class districts. Measured concentrations were consistently smaller than those estimated from the waste water fraction in groundwater samples, suggesting that DAs undergo removal processes in both reducing and oxidizing conditions.
LLOC: Edifici D2, Aula CIHS

24/05/2012: Seminari d'Hidrologia Subterrània

AUTOR: Daniel Pedretti
TÍTOL: On layer connectivity, a new indicator to control late-time scaling on breakthrough curves from conservative convergent flow tracer tests in heterogeneous media
DESCRIPCIÓ: Experimental breakthrough curves (BTC) observed during advection-dominated convergent-flow tracer tests usually show positively skewed, long-tailed distributions. In case of injection of conservative tracers, skewness can be related with the spatial variability of the flow fields, which depend on the multiscale heterogeneous geological background and on the aquifer boundary conditions imposed during the test. While many studies indicate flow and transport connectivity to play a central role in the control of BTC scaling, a quantitative explanation of the processes controlling connectivity and determining BTC skweness has not been found already. In this seminar, we define the concept of ‘layer connectivity’ as a possible indicator to determine the probability of BTC to display power-law slopes scaling as c~t-1 at late time. We describe the methodology to obtain this indicator, and some results we obtain after analyzing three well-defined heterogeneous environments, characterized by different correlation scales. We use a numerical approach to simulate flow and transport at detailed scales. We will show that the late-time scaling of BTC is controlled by the spread of the probabilistic density function of the layer connectivity (called 'IBC') evaluated by reproducing transport in each layer composing a 3D block, and comparing it with the flux-averaged 3D BTC. We note that if IBC is narrow, the 3D BTC show less pronounced tailing, while if the spread of IBC is higher, tailing on 3D BTC tends to scale like c~t-1 at late time. This study also demonstrates the inadequacy of unconditional multigaussian 2D models to reproduce solute transport in heterogeneous media, due to their scarce natural capacity to develop connected flow and transport paths.
LLOC: Edifici D2, Aula CIHS

29/05-01/06/2012: Curs de mobilitat - Màster i Doctorat en Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Manuel Pastor (Dep. de Matemáticas e Informática Aplicadas a la Ingeniería Civil, Universidad Politécnica de Madrid)
TÍTOL: Modelos de deslizamientos
DESCRIPCIÓ: Introducción a los fenómenos de propagación de deslizamientos; Modelos matemáticos (Generales, Biot-Zienkiewicz, Integrados en profundidad); Modelos constitutivos y reológicos (Rotura difusa: licuefacción, Modelos para suelos fluidificados); Modelos numéricos (Modelos en elementos finitos, Modelos de SPH)
LLOC: Edifici D2, Aula 212 i Edifici B1, Aula 101

17/05/2012: Seminari d'Hidrologia Subterrània

AUTOR: Silvia de Simone
TÍTOL: Thermo-hydro-mechanical simulation of geothermal reservoir stimulation
DESCRIPCIÓ: In Enhanced Geothermal Systems, hydraulic stimulation is carried out by injecting water into naturally fractured rocks, in order to improve permeability. These processes commonly trigger microseismic or seismic events. In general terms, induced seismicity occurs when the fluid overpressure is enough to generate a reduction of effective stress that produces failure conditions. In addition to the overpressures, it is important to consider that the water injected in the hot reservoir is cold. Thus, the large temperature contrast produces an extra reduction in effective stresses due to thermal strain.
The objective of this study is to test the conjecture that cold water injection produces mechanical instability not only due to hydraulic effects, but also due to coupled thermal effects. To test this conjecture, hydro mechanical (HM) and thermo hydro mechanical (THM) numerical simulations have been performed on a very simplified geometry of a fractured medium. The results confirm that indeed THM effective stresses are consistently more unstable (closer to a hypothetical yield surface) than HM effective stresses.
LLOC: Edifici D2, Aula CIHS

21/06/2012: Seminari d'Hidrologia Subterrània

AUTOR: Maarten Saaltink
TÍTOL: A method for incorporating chemical reactions into multiphase flow models for CO2 injection
DESCRIPCIÓ: CO2 injection in deep saline aquifers involves many different processes, including multiphase flow, heat and mass transport, rock deformation and mineral precipitation and dissolution. All these processes are coupled. Therefore, their modeling is difficult and requires complex computer codes to describe and assess them numerically. This document describes a method for incorporating chemical reactions into multiphase flow codes. It is limited to chemical systems that can be calculated as a function of the state variables of the multiphase flow model (e.g. liquid pressure, gas pressure, temperature). It consists of calculating the chemical composition of this system as a function of these state variables by means of chemical speciation codes and redefining the components of the multiphase flow code (e.g., water, CO2). We applied this method to incorporate chemical reactions of a H2O-CO2-Na-Cl-CaCO3 system into CodeBright, a code that can handle multiphase flow, heat transport, mass transport and deformation. We used this code to model CO2 injection into a saline aquifer containing calcite. The model could simulate well the interaction between the development of the CO2 bubble, dissolution of CO2 into the brine, calcite dissolution and density dependent flow.
LLOC: Edifici D2, Aula CIHS

28/06/2012: Seminari d'Hidrologia Subterrània

AUTOR: Maria Gabriela Dávila
TÍTOL: Efficiency of magnesium hydroxide sludge as an engineering seal in the geological sequestration of CO2
DESCRIPCIÓ: Injection of CO2 at depth will cause the acidification of groundwater. MgO is proposed as an alternative to Portland cement in wells. MgO carbonation is studied by means of batch experiments at 25, 50 and 90°C and pCO2 of 10 and 50 bar. Magnesium oxide reacts with CO2-containing water previously equilibrated with calcite, quickly hydrating to brucite (Mg(OH)2). Brucite dissolves causing the precipitation of magnesium carbonate phases. Precipitation of these secondary phases (magnesite and/or metastable phases such as nesquehonite MgCO3·3(H2O) or hydromagnesite Mg5(CO3)4(OH)2·4(H2O)) depends on pCO2 and temperature. Precipitation of the non-hydrated Mg carbonate is favored by increasing temperature and pCO2. The experimental variation of Mg and Ca concentrations and pH with time at the different temperatures and pCO2 is simulated using the CHEPROO-TRACONF reactive transport code. Simulations reproduce the experimental evolution of the aqueous concentrations and indicate a decrease in porosity when increasing temperature and pCO2. This decrease in porosity would be beneficial for the sealing properties of the cement. Simulations have also allowed the extrapolation of the experiments to CO2 supercritical conditions, which also show a decrease in porosity. These results have been applied to the simulation of an application case with a deep borehole surrounded by MgO cement. The CrunchFlow code has been used for this case.
LLOC: Edifici D2, Aula CIHS

05/07/2012: Seminari d'Hidrologia Subterrània

AUTOR: Leanne K. Morgan (Flinders University, Adelaide)
TÍTOL: Assessing seawater intrusion vulnerability at a national-scale using theoretically based vulnerability indicators
DESCRIPCIÓ: Coastal aquifers are an important water resource in Australia, where 85% of the population live within 50 km of the coast. Although the threat of seawater intrusion (SWI) has been reported in all of the states and the Northern Territory, comprehensive investigations of SWI are relatively uncommon. To address this gap, a national-scale vulnerability assessment of SWI is being carried out to assess aquifers currently affected by SWI and potentially at risk as a consequence of over-extraction, recharge change or sea-level rise. The project is comprised of three main components: 1) Coastal Aquifer Typology; 2) Vulnerability Factor Analysis; and 3) Mathematical Analysis. Outcomes of this nation-wide project will help to prioritise areas requiring further investigation and management of SWI. This study discusses the Mathematical Analysis component of the project. A method for first-order assessment of SWI vulnerability under both current conditions and future stresses (including sea-level rise, recharge change and reduced inflow from inland aquifers) has been developed as part of the project, as described by Werner et al. (2012). The methodology is an extension to the analytical sharp-interface solution of Strack (1976) and involves the use of partial derivatives to quantify rates of change in wedge toe location and seawater volume for the various stresses. Using this method, relative vulnerability under current conditions and to different stresses were determined for 28 case study areas identified by stakeholders as being of SWI concern.
LLOC: Edifici D2, Aula CIHS

05/07/2012: Seminari d'Hidrologia Subterrània

AUTOR: Leanne K. Morgan (Flinders University, Adelaide)
TÍTOL: A precautionary note on the interpretation of coastal aquifer water level trends and water balances
DESCRIPCIÓ: In many cases, seawater intrusion-induced interface movements and associated changes in seawater volume are not considered in coastal aquifer management studies. The conditions under which this simplified approach may result in incorrect estimates of freshwater volumes and flawed interpretations of water level trend analyses are not well understood. We address this gap using a simple steady-state, sharp-interface, analytic modelling approach to generate idealised relationships between seawater volume, freshwater volume and water levels. The results demonstrate that seawater volume changes impart significant influence on water level trends within coastal aquifers when compared to the corresponding non-coastal aquifer situation, particularly within deep aquifers with high hydraulic conductivity and low net recharge. Changes in seawater volume (over an assumed timescale) were found to be significant relative to freshwater discharge to the sea for a number of cases, especially within deep aquifers with low hydraulic conductivity, low net recharge and low water levels, at least for the idealised conditions of the analysis. These results highlight the importance of considering changes in seawater volumes within coastal aquifer water balances. The results also demonstrate that temporal trends in coastal aquifer water levels may not provide an adequate measure of freshwater storage trends, and rather, rapid assessment of coastal aquifer condition should consider groundwater levels relative to the hydraulic forcing of the ocean using an appropriate equivalent freshwater head for the ocean boundary condition.
The analytic solution used for this study involves an assumption of quasi-equilibrium conditions between the water table and interface. This assumption was evaluated using a selection of transient simulations, and preliminary results will be presented.
LLOC: Edifici D2, Aula CIHS

16-27/07/2012: Curs de Mobilitat

AUTOR: Tobias Licha (Universität Göttingen)
TÍTOL: Organic hydrochemistry
DESCRIPCIÓ: General introduction (Classes of organic compounds, Contaminant classes), Properties of organics (Name, Structure, Properties, Relationships), Distribution equilibria in various compartments of the subsurface environment, Dynamic processes for understanding the transport and fate of organics in the subsurface
LLOC: Edifici D2, Aula CIHS

16-20/07/2012: Curs de Mobilitat

AUTOR: Federica Cotecchia (Technical University of Bari)
TÍTOL: Mechanical behavior of natural clays in relation to composition, history and structure
DESCRIPCIÓ: Influence of Composition on clay mechanical response (Brief Review of clay mineralogy and index properties, Reconstituted clays, Review of critical state soil mechanics as reference framework for the behaviour of reconstituted clays, Modelling reconstituted clay behaviour, Experimental evidence of the influence of clay composition on the values of the mechanical parameters of reconstituted clays, Experimental evidence of the influence of composition on the compression behaviour of natural normally consolidated clays (Skempton data), Normalizing the clay mechanical response for composition), Deposition conditions and geological history of clays and resulting structures (Deposition environments, Definition and characterization of clay structures, Sedimentation structure and post‐sedimentation structure, Investigating the influence of structure on the clay response), Mechanical behaviour of unfissured clays (reconstituted and natural) in relation to structure (Compression behaviour, Shear behaviour (small strains), Shear behaviour (large strains), Normalizing the clay behaviour for structure, Modelling natural clay behaviour: approach and strategy), Mechanical behaviour of fissured clays (Compression behaviour, Shear behavior, Normalizing the fissured clay behaviour for the effects of fissuring, General framework of the influence of structure (from the micro to the meso‐scale) on clay behaviour)
LLOC: Edifici D2, Aula 212

19/07/2012: Seminari d'Hidrologia Subterrània

AUTOR: Jonny Rutqvist (Lawrence Berkeley National Laboratory)
TÍTOL: The geomechanics of CO2 storage in deep sedimentary formations
DESCRIPCIÓ: The presentation provides a review of the geomechanics and modeling of geomechanics associated with geologic carbon storage (GCS), focusing on storage in deep sedimentary formations, in particular saline aquifers. Geomechanical observations at current GCS field deployments, mainly at the In Salah CO2 storage project in Algeria, are also presented. The In Salah project, with its injection into a relatively thin, low-permeability sandstone is an excellent analogue to the saline aquifers that might be used for large scale GCS in parts of Northwest Europe, the U.S. Midwest, and China. Some of the lessons learned at In Salah related to geomechanics are discussed, including how monitoring of geomechanical responses is used for detecting subsurface geomechanical changes and tracking fluid movements, and how such monitoring and geomechanical analyses have led to preventative changes in the injection parameters. Recently, the importance of geomechanics has become more widely recognized among GCS stakeholders, especially with respect to the potential for triggering notable (felt) seismic events and how such events could impact the long-term integrity of a CO2 repository (as well as how it could impact the public perception of GCS). To date, no notable seismic event has been reported from any of the current CO2 storage projects, although some unfelt microseismic activities have been detected by geophones. However, potential future commercial GCS operations from large power plants will require injection at a much larger scale. For such large-scale injections, a staged, learn-as-you-go approach is recommended, involving a gradual increase of injection rates combined with continuous monitoring of geomechanical changes, as well as siting beneath a multiple layered overburden for multiple flow barrier protection, should an unexpected deep fault reactivation occur.
LLOC: Edifici D2, Aula CIHS

26/07/2012: Seminari d'Hidrologia Subterrània

AUTOR: Yann René Ramos Arroyo
TÍTOL: Modelació de quantitat i qualitat d'aigua en embassaments: Estudi de cas de l'Olivargas a Huelva
DESCRIPCIÓ:

El coneixement de la quantitat d'aigua disponible és fonamental per a estructurar plans de desenvolupament i assegurar un abastament segur a la població. En algunes regions del món l'única font d'aigua són els escorriments que s'emmagatzemen en embassaments. És necessari comptar amb models numèrics de predicció tant del volum d'aigua als embassaments com de la qualitat. El volum parteix d'una aproximació d'un balanç hídric a la conca de captació i a l'embassament on s'emmagatzema la massa d'aigües. La qualitat depèn de la litologia que existeix a la conca i de les interaccions entre l'aigua de pluja i els minerals.
Els models de predicció requereixen d'una descripció de la geometria de l'embassament per tal de simular processos de mescla, d'estratificació i conèixer les corrents a l'interior de la massa d'aigües.
El cas de l'embassament d'Olivargas és complicat degut a tres aspectes:

 

  • L'anàlisi històric del clima i la hidrologia mostra períodes de sequera i de pluges intenses difícils de predir
  • Els rierols que hi vessen reben drenatges de mines i lixiviats de residus de sulfurs massius
  • La geometria de l'embassament afavoreix una zonació en els processos de precipitació de minerals a la columna d'aigua i la diagènesi en els sediments mostra una alta variabilitat espacial

Per altra banda, una limitació a l'hora d'aconseguir adaptar un model de predicció i calibrar-ho és la manca de dades històriques de la hidrologia degut a que no existeix una adequada instrumentació.
Es mostren els processos al interior de la massa d'aigües suportats en una caracterització hidrogeoquímica realitzada l'any hidrològic 2009-2010.
LLOC: Edifici D2, Aula CIHS

20/09/2012: Seminari d'Hidrologia Subterrània

AUTOR: Dr. Richard J. Bathurst (Professor del GeoEngineering Centre del Queen's-RMC a Kingston, Ontario (Canadà) y President-electe de la Canadian Geotechnical Society)
TÍTOL: Recent developments in reinforced soil wall technologies
DESCRIPCIÓ: Reinforced soil walls including structures with steel and geosynthetic reinforcing elements are now well-established technologies. Nevertheless, there remain questions regarding the accuracy of current internal stability analyses of geosynthetic reinforced soil walls that are based on limit equilibrium concepts. The accuracy of strength-based methods of analysis for reinforcement rupture and pullout design of walls under operational conditions has become an issue in North America as design practice moves to limit states design based on rigorous calibration using reliability theory. Measured and predicted reinforcement loads using current tie-back methods are compared and predicted values shown to be very poor on average for geosynthetic reinforced soil walls but reasonably accurate for steel reinforced soil walls. Sources of poor prediction accuracy are identified using results of instrumented full-scale walls and numerical modeling. The essential features of a new empirical-based working stress design method (K-stiffness Method) are presented. This new method explicitly includes the influence of reinforcement stiffness (steel and geosynthetics) and the structural facing amongst other contributions. The talk will also include examples of new reinforced soil wall technologies in North America and Asia as well as new test methods and interpretation for the quantification of facing component performance and reinforcement strength limit states.
LLOC: Edifici D2, Aula 212

20/09/2012: Seminari d'Hidrologia Subterrània

AUTOR: Linda Luquot
TÍTOL: Lab scale characterisation of hydrochemical processes triggered by CO2 injection in reservoirs
DESCRIPCIÓ: CO2 sequestration in deep geological formation seems to be a good solution for minimizing CO2 emissions in the atmosphere. In the vicinity of the injection well, scCO2 will dissolve in the brine and produce low pH solution favouring dissolution of carbonate and to a less extent silicate minerals. Consequently, important modifications of the rock properties (hydrodynamical and mechanical) are expected. Characterizing and modelling these mechanisms is essential for predicting short- and long-term behaviour.
Here, we present results of three percolation experiments which reproduced in situ CO2 injection into an oolithic limestone for different value of Damköhler number (ie. different partial pressure of CO2). X-ray microtomography (XMT), using ID19 at ESRF, is used to characterize, from pore scale to Darcy scale, the changes in the structural properties induced by the percolation of the CO2-rich brine. Coupling imaging techniques with sample scale measurements of the time-resolved permeability and chemical fluxes, allows determining i) the change in the chemical and physical parameters of the sample (porosity, reactive surface area, tortuosity) induced by the dissolution processes and ii) the role of each phase in the formation of the observed preferential flow path (or wormhole like structures). We also present some results on CO2 rich brine injection through sandstone sample coming from Otway Basin (Australia). We characterized, CO2 precipitation as reduce carbon phases and clays precipitation. Finally, we present some results on CO2 rich brine injection through fractured cement sample to evaluate CO2 leakage.
LLOC: Edifici D2, Aula CIHS

07/09/2012: Seminari de Recerca

AUTOR: Prof. Haluk Sucuoglu (Professor del Departament d'Enginyeria Civil al Middle East Technical University (METU))
TÍTOL: Energy dissipation characteristics of reinforced concrete columns
DESCRIPCIÓ: Energy dissipation capacity of reinforced concrete columns is investigated under inelastic cyclic displacements in the first part. Experimental data is obtained from twenty column specimens tested under constant amplitude displacement cycles and from three column specimens tested under variable amplitude displacement cycles. The effect of failure mode, displacement ductility, material properties and detailing on the energy dissipation capacity of columns is investigated first under constant-amplitude loading. A simple model is developed for predicting the cyclic energy dissipation capacity under constant-amplitude inelastic displacement cycles. Then an analytical procedure is introduced for estimating the energy dissipation under variable-amplitude displacement cycles by using the energy dissipation capacity under constant-amplitude displacements. The proposed procedure is verified with test results.
In the second part, an energy-based hysteresis model is developed for the moment-rotation (curvature) response of columns with flexural response. The model accounts for deterioration in cyclic energy dissipation capacity as well as strength and stiffness, including pinching. Energy dissipation is utilized as a memory agent in determining the load-path dependency of hysteresis cycles. Cyclic energy dissipation capacity constrains the constructed hysteresis cycles. This capacity is determined from the analytical energy dissipation model developed in the first part. Experimental data obtained from eleven column specimens responding in pure flexure under constant and variable amplitude displacement cycles are employed. The proposed hysteresis model is verified with experimental observations.
LLOC: Edifici C1, Aula Zienkiewicz

04/10/2012: Seminari d'Hidrologia Subterrània

AUTOR: Florian Doster (Princeton University)
TÍTOL: Hysteresis in two-phase flow in porous media
DESCRIPCIÓ: Understanding macroscopic phenomena of two-phase flow in porous media is of great interest for applications such as irrigation, dike construction, contaminant remediation in the subsurface, oil recovery, CO2-sequestration etc. Further, two-phase flow in porous media is very interesting from a more fundamental science oriented and physical perspective, since many of the observed phenomena still lack a profound understanding. Last but not least, it is also a great challenge from a mathematical perspective because of the non-linear partial differential equations occurring in most of the models and the strong coupling between different length scales. In my talk I will focus on path-dependency, i.e. hysteresis, of the constitutive parameter functions of the standard model and illustrate mathematical implications, modeling challenges and possible applications.
LLOC: Edifici D2, Aula CIHS

11/10/2012: Seminari d'Hidrologia Subterrània

AUTOR: Anna Russian
TÍTOL: Modeling anomalous scaling of groundwater levels and discharge with double and multicontinuum models
DESCRIPCIÓ: One of the main processes in the basin-scale water cycle is the groundwater recharge from precipitation and the consequent discharge of the catchment into a river or any outfall. Thus, a clear understanding of the dynamics of the groundwater system and the recharge processes is fundamental to improve our ability to manage groundwater resources. Variations in groundwater levels represent the dynamic response of an aquifer to changes in recharge. The aquifer dynamics is modeled as a linear input-output problem, where the input (the rainfall) and the output (hydraulic groundwater head variation or the consequent discharge) are related by a transfer function. In spectral analysis, used to highlight periodicity in the recharge process, the frequency transfer function (!) is given by the ratio of the power spectra of aquifer response (groundwater level or discharge) and recharge. Classical models, such as the Dupuit and linear models predict that the transfer function scales with frequency as (!)  !− with exponents equal to = 1 and = 2, respectively [Gelhar 1974].
Scaling behaviors with exponents that are not equal to 1 or 2 are called anomalous. Anomalous temporal scaling are commonly explained by fractal models, which, however, often lack a relation to the medium characteristics and are rather descriptive. Here we employ a multicontinuum approach to describe such anomalous behavior. This approach is based on a stochastic description of the medium heterogeneity, and thus, in principle, allows to relate the catchment response to the distribution of hydraulic parameters. The proposed multi-continuum model can explain scaling exponents 1/2 < < 2 based on a broad distribution of storage time scales in different regions of the spatially heterogeneous medium.
LLOC: Edifici D2, Aula CIHS

18/10/2012: Seminari d'Hidrologia Subterrània

AUTOR: Ester Torres
TÍTOL: Diffusion-reaction modelling of early diagenesis of sediments affected by acid mine drainage
DESCRIPCIÓ: The Sancho Reservoir (SW Spain) is a monomictic water reservoir affected by acid mine drainage. It has a pH of ~4, with high sulfate (200 ppm) and heavy metal concentrations in the water column. The reservoir develops reducing conditions at the bottom during the stratification period. A laboratory experiment was carried out to study the effect of this oxygen variation on the early diagenesis processes and the cycling of metals. Sediment cores and bottom water were collected during the stratification period and brought to the laboratory. The cores were maintained in an aquarium bubbled with nitrogen gas to maintain hypoxic conditions (~10 µmol O2 L-1) for 1 day. Then, oxic conditions were induced by bubbling with air and maintained for 50 days. Finally, hypoxia was re-established for 10 days. Triplicate cores were sliced in an anaerobic glove box at each stage. Pore water was extracted by centrifugation and: Eh, pH, DO, DOC, sulfate, Fe and trace metals were analyzed. The sediment was freeze-dried and a sequential extraction protocol was applied to determine the exchangeable, AVS, Fe-(oxy)hydroxides, Fe-oxides, organic matter, pyrite sulfur and residual phase iron fractions. Organic carbon and total C, N, H and S were also analyzed in the sediment. A reactive diffusion model has been used to obtain the rates of biogeochemical reactions by fitting to the experimental data. During hypoxic conditions sulfate and Fe-(oxy)hydroxides are reduced, due to the anaerobic oxidation of organic matter, at the very first few cm, releasing sulfide and Fe(II) which precipitate as iron sulfide. When oxygen diffuses into the sediment, sulfate-reduction and the sulfide peaks are displaced deeper into the sediment. Oxygen penetration depth and its consumption rates in the sediment increase quickly, resulting in the reoxidation of the iron sulfides that had precipitated during hypoxic conditions. Sulfide and Fe(II) are released and are again oxidized to Fe(III) and sulfate respectively. Arsenic can be adsorbed onto the iron sulfides and pyrite. During the dissolution of the iron sulfide As will be released and will diffuse to the water column. Copper and zinc can also precipitate as metal sulfides.
LLOC: Edifici D2, Aula CIHS

24/10/2012: Darcy Lectures

AUTOR: S. Majid Hassanizadeh (Utrecht University)
TÍTOL: Capillarity in porous media, on micro- and macroscale, revisited
DESCRIPCIÓ: In many soil and aquifer systems, one encounters simultaneous movements of two or more immiscible fluids. These systems are modeled using a modified form of Darcy’s law, mass or volume balance equations, and an empirical relationship between capillary pressure and saturation. In this lecture, Hassanizadeh will:
  • Explain the general understanding that capillary pressure is equal to the difference in pressures of two fluids. At microscale, this difference is given by the Young-Laplace equation, which prescribes an inverse relationship with the mean radius of curvature. At macroscale, the difference in fluid pressures is assumed to be an algebraic empirical function of saturation, as mentioned above.
  • Provide a unifying approach to the theory of capillarity based on rational thermodynamics.
  • Present alternative definitions of capillary pressure on both micro- and macroscales. In particular, Hassanizadeh will make a clear distinction between capillary pressure and pressure difference of fluids.
  • Show that the difference in fluid pressures is a function of boundary conditions and dynamic properties of the system, such as flow rate or dynamic viscosities, based on theoretical, experimental, and computational results.
  • Propose that the capillary pressure must be an intrinsic property of the fluids/solid system and independent of dynamics of the system.
  • Introduce specific interfacial area (area of fluid/ fluid interfaces per unit volume of porous medium) as a new state variable to account for the fact that capillary pressure is a surface phenomenon and not a volumetric one.
  • Present theoretical, experimental, and computational evidences that show the empirical capillary pressure-saturation curve should be replaced with the capillary pressure-saturation-interfacial area surface rooted in thermodynamic theory.
LLOC: Edifici D2, Aula 212

25/10/2012: Darcy Lectures

AUTOR: S. Majid Hassanizadeh (Utrecht University)
TÍTOL: Transport of viruses in partially saturated soil and groundwater
DESCRIPCIÓ:

Surface water is often used for recharge of aquifers used in drinking water production. But it can be contaminated with pathogenic microorganisms and viruses from wastewater discharges or manure runoff. These pathogens have to be removed to produce safe drinking water such as passing surface water through soil. However, to assure production of safe drinking water from surface water, adequate travel times and travel distances are needed. In this regard, it is important to determine various factors that affect the rate of removal of pathogenic viruses during soil passage. These factors include hydraulic conditions (such as flow velocity and saturation) and geochemical conditions (pH, ionic strength, concentration of calcium). In this lecture, Hassanizadeh will:


  • Present the results of a large number of laboratory and field experiments involving bacteriophages (viruses affecting bacteria), which were carried out under a variety of conditions under steady-state flow settings.
  • Show how the data from the experiments was used to derive (empirical) relationships between removal rate coefficients and geochemical conditions as well as saturation.
  • Explain how in the case of unsaturated flow, the role of air/water interfaces in the removal of viruses was also investigated.
  • Present findings from experiments performed under transient flow conditions where saturation has been changed significantly.
  • Show how the experiments, as well as other researchers’ results, have demonstrated that both drainage and imbibition fronts cause a remobilization of adsorbed viruses.
  • Discuss the mechanisms behind this remobilization.
  • Provide evidence from pore-scale visualization experiments performed in a micromodel.
LLOC: Edifici D2, Aula CIHS

07/11/2012: Seminari de Recerca

AUTOR: Anitha Kumari (Department of Civil Engineering, IISc, Bangalore)
TÍTOL: Particle shape effects on the mechanical behaviour of granular materials: Discrete element simulations
LLOC: Edifici D2, Aula 212

08/11/2012: Seminari d'Hidrologia Subterrània

AUTOR: Katrien de Pourcq
TÍTOL: Ensayo de trazadores en una barrera reactiva permeable para la retención de Cesio-137 en la normalización del centro de recuperación de Inertes (CRI) en las Marismas de Mendaña (Huelva)
DESCRIPCIÓ: Debido a la fusión accidental de una fuente de 137Cs en una instalación siderúrgica, se vertió material contaminado en la balsa n. 9 del Centro de Recuperación de Inertes (CRI-9), situado en las marismas de Mendaña (Huelva). Como consecuencia, se ejecutó un plan de normalización del CRI-9 en que se retiró el polvo contaminado cuya tasa de dosis superara los 100 mSv/h y se trasladó al Centro de Almacenamiento de Residuos de Media y Baja Actividad de El Cabril, en Córdoba. El resto de material menos contaminado se encuentra actualmente en el CRI-9.
El acondicionamiento in situ de las partes más contaminadas, consistió en cubrirlas con una capa de arcilla de 1,5 m de espesor para disminuir la entrada de agua. Desde entonces se inició un plan de vigilancia radiológico de la zona. Durante unas actuaciones se observaron dos zonas de filtración de agua de escorrentía en zonas muy localizadas de la balsa. Por ello, se requirió la realización de un nuevo plan de remediación que evitase la salida de 137Cs al exterior. El nuevo plan consistió en una mayor caracterización de la zona y la colocación de una barrera reactiva permeable que retenga el 137Cs que pueda migrar con las aguas subterráneas.
Para verificar posteriormente la eficacia de la barrera en la retención de Cs-137 así como su correcto funcionamiento hidráulico, se propuso realizar un ensayo de inyección de agua con concentraciones más elevadas de Cs-137. Junto con el Cs-137 se inyectaron dos trazadores conservativos (no reactivos) con el fin de confirmar la extracción en el pozo de bombeo del agua inyectada. En este seminario se presentarán los resultados del ensayo y las conclusiones obtenidas hasta el momento.
LLOC: Edifici D2, Aula CIHS

15/11/2012: Seminari de Recerca

AUTOR: Wangcheng Zhang (Tongji University)
TÍTOL: An investigation on loose cemented granular materials via DEM analyses
LLOC: Edifici D2, Aula 212

15/11/2012: Seminari d'Hidrologia Subterrània

AUTOR: Jordi Cama
TÍTOL: Experimental study of calcite interaction with acidic sulfate solutions
DESCRIPCIÓ: In the contexts of AMD-limestone treatments and geological CO2 sequestration in saline aquifers, calcite dissolution was investigated by means of ex situ VSI (Vertical Scanning Interferometry) and EDXRF measurements at ambient pCO2, acidic pH and room T in metal (Fe(II), Zn, Cu and Cd) and metal-free chloride and sulfate solutions. It is shown (1) the effect of the divalent cations and sulfate on calcite dissolution and (2) the precipitation of gypsum and metal sulfate on dissolving calcite.
LLOC: Edifici D2, Aula CIHS

22/11/2012: Seminari de Recerca

AUTOR: Douglas Morrison (President & CEO, Centre for Excellence in Mining Innovation, Sudbury, Ontario, Canada)
TÍTOL: Opportunities in geotechnical research in deep hard-rock mines in Canada
LLOC: Edifici D2, Aula 212

22/11/2012: Seminari d'Hidrologia Subterrània

AUTOR: Meritxell Gran
TÍTOL: Balances de agua y energía del modelo de flujo multifase no isotermo de una cobertura para residuos de baja y media actividad
DESCRIPCIÓ: El Cabril és el centre d'emmagatzematge de residus radioactius de mitja, baixa i molt baixa activitat d'Espanya, està situat a Còrdoba i administrat per ENRESA. A les seves instal·lacions s'ha construït una cobertura pilot per a simular el confinament definitiu dels residus. L'objectiu d'aquesta cobertura és garantir que durant aproximadament 300 anys no es produeixi cap tipus d'entrada d'aigua, en fase líquida o vapor, ni de cap vegetal o animal, que puguin posar en perill l'aïllament dels residus.
L'assaig està format per dos sistemes multicapa que han estat instrumentats amb més de 200 sensors per a prendre mesures de contingut d'aigua, pressió-succió, temperatura, flux de calor, propietats tèrmiques i inclinació i deformació de la làmina de PEAD (material impermeable que envolta la cobertura convertint-la en un gran lisímetre). Es disposa de llargues sèries temporals de dades recollits insitu que s'estan utilitzant per a validar el model numèric. Aquest és un model 1D de flux multifase no isoterm amb condició de contorn atmosfèrica aplicada en superfície. En aquest seminari es descriuran els detalls d'aquest model i es mostraran els resultats obtinguts fins ara. Es discutiran els balanços d'energia i d'aigua (fase líquida i vapor) i s'exposaran els problemes que en sorgeixen.
LLOC: Edifici D2, Aula CIHS

29/11/2012: Seminari d'Hidrologia Subterrània

AUTOR: Jorge Jodar
TÍTOL: Plataforma de hospedage de modelos numéricos mediante cloud computing
DESCRIPCIÓ: Tradicionalment els models numèrics en hidrologia han estat valuoses eines utilitzades per a planificar l'us dels recursos hídrics. Donada la complexitat que comporta implementar i utilitzar un model fa que aquests siguin emprats només per tècnics especialitzats. Aquests models solen proporcionar resultats de difícil us per personal no especialitzat, i les preguntes prioritàries del Gestor del recurs solen requerir complexos processos de maneig de l'eina. Però planificar no significa gestionar. Per a que el model sigui una eina de recolzament a la gestió és necessari que sigui fàcil de fer servir i doni respostes clares i fiables a les preguntes que es fa un gestor, no necessàriament les mateixes que faria l'expert en modelació. A més, utilitzar el model numèric per a abordar solucions, o bé a possibles contingències, o bé a les necessitats canviants de la gestió, implica disposar del model constantment actualitzat. Això no és fàcil i requereix d'un esforç, dedicació i temps gens menyspreable. Davant dels reptes que suposa l'us dels models numèrics com a eines de recolzament a la gestió i a la presa de decisions hem desenvolupat l'aplicació GAC (Global Aquifer Control), basada en tecnologia del Cloud Computing. El GAC és capaç d'allotjar a la seva plataforma models numèrics i els actualitza de manera automàtica, independentment del codi en el qual el modelo hagi estat implementat. L'us de l'aplicació és senzill i es realitza des del navegador d'Internet: els escenaris possibles s'han simplificat per a facilitar al màxim el seu us. A més, gràcies al Cloud, la plataforma permet l'accés i execució del model de tants usuaris simultanis com sigui necessari sense que això suposi un detriment en el temps de càlcul o la transferència de resultats.
LLOC: Edifici D2, Aula CIHS

13/12/2012: Seminari de Recerca

AUTOR: Jingde Liu (Dept. Geotechnical Engineering, Tongji University)
TÍTOL: A micro-mechanical based constitutive model for structured soils
LLOC: Edifici D2, Aula 212

20/12/2012: Seminari de Recerca

AUTOR: Prof. Erich Bauer (Institute of Applied Mechanics, Graz University of Technology)
TÍTOL: Hypoplastic modelling of shear banding in granular bodies
DESCRIPCIÓ: The evolution of shear bands in a soil body can either be spontaneous or forced. While the former is related to a material instability, the latter is triggered by the interface behaviour of the soil material in contact with a rough bounding structure under shearing. The problem of shearing along a rough bounding structure is of interest in many geotechnical applications, such as retaining walls, piles, anchors, soil nailing and reinforced earth structures. The focus of the lecture is on modelling shear localization in cohesionless soil using a continuum description based on the framework of hypoplasticity. The onset of shear strain localization is investigated based on a bifurcation analysis. In order to study the further evolution of shear bands a micro-polar hypoplastic model is used. The constitutive relation for the stress tensor and the couple stress tensor is described using tensor-valued functions which are non-linear in the rate of deformation and the rate of curvature. Besides the mean grain size, which is included in the constitutive relations as the characteristic length, the micro-polar boundary conditions also have a strong influence on the thickness and location of the localized zone. For rough surfaces of the bounding structure the forced shearing leads to a localization of the deformation in the soil layer and to an increase of the void space in this zone. The displacement field within the localized zone is non-linear from the beginning of shearing. It is shown that the thickness of the band with a higher void space needs not to be related to the active thickness of the localized zone, which can change during shearing. Thus the thickness of shear bands is not a material constant and mainly depends on the grain size, grain shape and surface roughness, the initial density, the stress state, the dilatancy resistance of the overall structure, the surface roughness of the bounding structure and the amount of the applied shear displacement.
LLOC: Edifici D2, Aula 212

17/12/2012: Seminari de Recerca

AUTOR: Varios
TÍTOL: Introducción al análisis automático de estructuras: de la teoría variacional al método de los elementos finitos. Técnicas de análisis numérico
LLOC: UPC-Urgell, EUETIB, Aula 9

17/12/2012: Seminari de Recerca

AUTOR: Varios
TÍTOL: Aplicaciones de métodos numéricos para el estudio de edificios de fábrica: ejemplos del programa Por de Newsoft
LLOC: UPC-Urgell, EUETIB, Aula 9

20/12/2012: Seminari d'Hidrologia Subterrània

AUTOR: Alberto Bellin (Department of Civil, Environmental and Mechanical Engineering, University of Trento, Italia)
TÍTOL: On modeling hyporheic dissolved oxygen and nitrogen dynamics in gravel bed rivers
DESCRIPCIÓ: Dissolved inorganic nitrogen (DIN), naturally a limiting element in pristine watersheds, has received recently great attention because of its increasing concentrations in water bodies due to anthropic activities. DIN concentrations regulate riverine ecosystems and organisms’ metabolism with important processes occurring in hyporheic, riparian and parafluvial zones, whose biochemistry is influenced by subsurface flow patterns. Although a large body of experimental evidences confirms this, most of the models used to represent nutrients cycling in fluvial ecosystems lump these processes in a single diffusion-type exchange term. In this seminar I discuss a new modeling approach, which overcomes this limitation. In particular, I will discuss a three-dimensional semi-analytical process-based model that couples hyporheic flow patters with dissolved oxygen and DIN biochemical processes within the streambed sediment. Flow patterns, are obtained analytically, with a few simplifying assumptions, from the streambed topography and solute transport is modeled within a Lagrangian framework chiefly as an advective process with temperature-dependent reaction rate coefficients derived from field experiments. In addition, I will discuss the application of this model to investigate the role of hyporheic flow induced by alternate bars - an ecologically important and ubiquitous bed form in both regulated and natural streams - on DIN dynamics. This modeling approach allows to investigate the effect of bedforms, alluvium depth, hyporheic water temperature and relative abundance of ammonium and nitrate in stream waters on DIN dynamic. Published results demonstrate how the model can be used to estimate nitrogen gas emissions from rivers.
LLOC: Edifici D2, Aula CIHS

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Tesis doctorals

19/01/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Javier Dopazo Álvarez
TÍTOL: Análisis de túneles de dovelas mediante Elementos Finitos. Esfuerzos en sostenimiento, movimientos del terreno y seguridad en el diseño
DIRECTOR: Alberto Ledesma

19/01/2012: Defensa de Proposta de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Clara Alvarado de Menéndez
TÍTOL: Comportamiento hidro-mecánico de materiales granulares gruesos
DIRECTOR: Eduardo Alonso Pérez de Ágreda
CODIRECTOR: Enrique Romero Morales

19/01/2012: Defensa de Proposta de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: M. Carme Chaparro Sanchez
TÍTOL: Flujo multifase y transporte de tritio en el hormigón del centro de almacenamiento de residuos radioactivos El Cabril
DIRECTOR: Maarten Saaltink

19/01/2012: Defensa de Proposta de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Carles Raimat Quintana
TÍTOL: Análisis de la dinámica y peligrosidad de las corrientes de derrubios en el Pirineo Catalán: Aplicación en el Barranco de Erill
DIRECTOR: Jordi Corominas
CODIRECTOR: Marcel Hürlimann

19/01/2012: Defensa de Proposta de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Hui Wang
TÍTOL: Characterize behaviour of emergent pollutants in artificial recharge: Column experiments
DIRECTOR: Jesús Carrera
CODIRECTOR: Carlos Ayora
TUTOR: Maarten Saaltink

30/01/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR
: Mariana Rodríguez
TÍTOL: Aplicaciones del análisis meso-mecánico con elementos juntas a probetas de hormigón sometidas a fractura en modo mixto y altas temperaturas
DIRECTOR: Ignasi Carol Vilarasau
CODIRECTOR: Carlos María López Garello

03/02/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Naile Aguirre Carvajal
TÍTOL: Magnetorheological dampers: Modeling and control design for civil engineering structures
DIRECTORS: Fayçal Ikhouane i José Rodellar

08/02/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Pablo Fernández Áznarez
TÍTOL: Rotura de un dique en el puerto de Barcelona. Análisis, modelación numérica y diseño alternativo
DIRECTORS: Núria Pinyol Puigmartí
CODIRECTOR: Eduardo Alonso Pérez de Ágreda

12/03/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Jubert Pineda
TÍTOL: Swelling and degradation of argillaceous rocks induced by relative humidity effects: an experimental study
DIRECTORS: Eduardo Alonso Pérez de Ágreda i Enrique Romero

30/03/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Ricard Poch Massegú
TÍTOL: Riego y fertilización nitrogenada en maiz (Zea Mays L.): Efecto sobre el rendimiento del cultivo y la contaminación subterránea por nitratos
DIRECTOR: Francisco Ramírez de Cartagena Bisbe

14/05/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Samuel França Amorim
TÍTOL: Estudio comparativo de metodos para la evaluacion de la susceptibilidad del terreno a la formacion de deslizamientos superficiales: Aplicación al Pirineo Oriental
DIRECTORS: Jordi Corominas i Nieves Lantada

22/06/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Ester Tarela Alonso
TÍTOL: Monitorización de la interacción frágil-dúctil de la litosfera y su relación con grandes terremotos
DIRECTOR: Luis Pujades Beneit

26/06/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Máximo Germán Peralta Álvarez
TÍTOL: Análisis estático no lineal y análisis dinámico no lineal del Hospital de Vielha
DIRECTOR: Yeudi Felipe Vargas
CODIRECTOR: Luis Pujades Beneit

29/06/2012: Defensa de Propostes de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Reyes Indira Herrera Gonzalez
TÍTOL: Vulnerabilidad y daño sísmico de edificios de hormigón armado porticados en Barquisimeto-Venezuela
DIRECTOR: Horia Alejandro Barbat Barbat
CODIRECTOR: Lluis Pujades Beneit
TUTOR: Lluis Pujades Beneit

29/06/2012: Defensa de Propostes de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Sonia Alexandra Santos Assunçao
TÍTOL: GPR ability evaluation in seismic risk studies
DIRECTOR: Maria de Vega Perez Gracia
CODIRECTOR: Jose Ramón Gonzalez Drigo
TUTOR: Oriol Caselles Margollin

29/06/2012: Defensa de Propostes de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Edgar Segués Aguasca
TÍTOL: Proposal of a dissipative connection for timber structures
DIRECTOR: Francesc López Almansa
CODIRECTOR: Inmaculada Rodríguez Cantalapiedra
TUTOR: Francesc López Almansa

29/06/2012: Defensa de Propostes de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Ronald David Ugel Garrido
TÍTOL: Vulnerabilidad sísmica en edificaciones porticadas compuestas de acero y hormigón armado
DIRECTOR: Horia Alejandro Barbat Barbat
CODIRECTOR: Lluis Pujades Beneit
TUTOR: Lluis Pujades Beneit

29/06/2012: Defensa de Propostes de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Fahit Gharibnezhad
TÍTOL: Submitted to the commission of the PHD program in Earthquake Engineering and Structural Dynamics
DIRECTOR: Josep Rodellar Benedé
CODIRECTOR: Luis Eduardo Mujica Delgado
TUTOR: Oriol Caselles Margollin

29/06/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Alicia Sanz Prat
TÍTOL: On the relationship between connectivity and reaction rates
DIRECTOR: Daniel Fernández García

07/09/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Ahmet Utku Yazgan
TÍTOL: Proposal of energy spectra for earthquake resistant design based on Turkish registers
DIRECTORS: Francesc López Almansa i Amadeu Benavent Climent:

27/07/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Eliana García Castaño
TÍTOL: Cambio de humedad en terraplenes bajo acciones climáticas. El caso del terraplén de la desviación de Carmaux, Francia
DIRECTOR: Jean Vaunat

27/07/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Isabel Aguirre Errecalde
TÍTOL: Modelling the SM-3 dam, Quebec, Canada
DIRECTOR: Núria Mercè Pinyol Puigmartí

27/07/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Albert Carles Brangarí
TÍTOL: Substrate bacterial dynamics in soils: a combination of theoretical and experimental approaches
DIRECTOR: Xavier Sànchez Vila

20/07/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Víctor Vilarrasa Riaño
TÍTOL: Thermo-hydro-mechanical impacts of Carbon Dioxide (CO2) injection in deep saline aquifers
DIRECTOR: Jesús Carrera Ramírez
CO-DIRECTOR: Sebastià Olivella Pastallé

15/10/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Donald Membreño
TÍTOL: Análisis de estabilidad de taludes por el método de elementos finitos: aplicación al terraplén de entrada viaducto de Más Rubió
DIRECTOR: Antonio gens Solé

19/10/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria Sísmica i Dinàmica Estructural

AUTOR: Salim Jesús Silveira Inatty
TÍTOL: Variación de las frecuencias propias de vibración del suelo debido a cambios rápidos en la litologia. Aplicación a Barcelona
DIRECTOR: Oriol Caselles Magallón

30/10/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Francisco Ernesto Moquete Rosario
TÍTOL: Evaluación del riesgo sísmico en edificios especiales: Escuelas. Aplicación a Barcelona
DIRECTOR: Nieves Lantada Zarzosa
CO-DIRECTOR: Lluis Pujades Beneit

21/12/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Daniele Pedretti
TÍTOL: Tools and analysis of spatio-temporal dynamics in heterogeneous aquifers: Applications to artificial recharge and forced-gradient solute transport
DIRECTORS: Franciso Javier Sánchez Vila, Daniel Fernández García i Diogo Bolster

11/12/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Diosenia Casalinuovo
TÍTOL: Ensayos de laboratorio sobre cambios en los parámetros de transporte por procesos de disolución
DIRECTOR: Tobias Rötting

26/09/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Jordi Font-Capó
TÍTOL: Interaction between groundwater and TBM (Tunnel Boring Machine) excavated tunnels
DIRECTORS: Enric Vázquez Suñé i Jesús Carrera

13/12/2012: Defensa de Tesi Doctoral - Doctorat en Enginyeria del Terreny

AUTOR: Mario Zarroca Hernández
TÍTOL: Application of 2D Electrical Resistivity Imaging (ERI) to geomorphological research in complex groundwater flow patterns
DIRECTOR: Rogelio Linares Santiago

18/12/2012: Lectura de Treball Final de Màster d'Enginyeria del Terreny i Enginyeria Sísmica

AUTOR: Jordi Serret i Magaz
TÍTOL: Fatiga de cimentaciones bajo cargas cíclicas: Aplicación al caso de la eólica marina
DIRECTOR: Marcos Arroyo Álvarez de Toledo

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Personal

Concursos
01/02/2012: Convocatòria d’una beca d'aprenentatge

Títol del projecte: BPE-àrea geotècnica
Descripció: Suport en la classificació, ordenació i digitalització de l’arxiu de l’Àrea de Geotècnia


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Premis

04/06/2012: El Prof. Eduardo Alonso pronuncia la Primera Heim Lecture a Banff (Canadà)

La Conferència és una iniciativa del "Joint Technical Committee 1", que és un comitè científic creat per les tres societats principals en el camp de la Geotècnia: ISSMGE (International Society of Soil Mechanics and Geotechnical Engineering), ISRM (International Society of Rock Mechanics) i IAEG (International Association of Engineering Geology).
El Comitè Científic JTC1 sobre “Talussos naturals i esllavissaments” ha instaurat una Conferència Internacional en honor a Albert Heim, que es celebrarà cada 4 anys durant el Simposi Internacional d'Esllavissaments.
Segons les paraules del comitè:
La persona encarregada de pronunciar la Heim Lecture ha de ser un investigador o professional en actiu amb gran experiència en el camp dels esllavissaments i/o fenòmens relacionats. Haurà de ser un bon comunicador capaç d'il.lustrar idees avançades que es considerin noves en el moment de la conferència i que posi de manifest la vitalitat i força d'aquest camp d'estudi. El futur conferenciant haurà de comptar amb un currículum en el camp de la Mecànica de Sòls, Mecànica de Roques i Enginyeria Geològica i ser capaç de comunicar-se a nivell tècnic amb investigadors i professionals pertanyents a altres camps.
El JTC1 va escollir al Professor Eduardo Alonso de la Universitat Politècnica de Catalunya per a ser la primera persona en pronunciar la Heim Lecture. La conferència va tenir lloc a Banff (Canadà) el 4 de juny del 2012, durant el XI Simposi Internacional d'Esllavissaments, sota el títol: "Deformation analysis of landslides. Progressive failure, thermal interactions and rate effects".

 

02/10/2012: Núria Pinyol rep el Premi Extraordinari de Doctorat

La Universitat Politècnica de Catalunya ha atorgat a NÚRIA MERCÈ PINYOL PUIGMARTÍ el Premi Extraordinari de Doctorat 2012 a la tesi presentada a la convocatòria 2009-2010 en el àmbit de l'Enginyeria Civil titulada: "Landslides in reservoirs. A coupled thermo-hydromechanical approach".

DIRECTOR: Eduardo Alonso i Jean Vaunat

DESCRIPCIÓ: La ocurrència d'esllavissaments és un dels principals problemes presents durant el disseny, construcció i explotació de presses i embassaments. La inundació del peu dels talussos, així com el desembassament ràpid, poden provocar primeres ruptures o reactivar antics esllavissaments, existents amb freqüència a l'entorn dels embassaments. Aquesta Tesi es centra en el cas particular de les esllavissades als marges d'embassaments on una massa de terreny esllavissa sobre una superfície de tall ben definida sense que s'observi una intensa degradació del material mobilitzat. A la primera part de la Tesi es discuteix el desembassament ràpid com un problema acoblat de flux i deformació en condicions saturades/no saturades. Un risc addicional apareix quan l'esllavissament accelera i envaeix l'embassament a gran velocitat, generant una onada. La discussió dels fenòmens responsables de l'acceleració dels esllavissaments continua actualment activa. Probablement la manca de casos ben documentats dificulta el progrés en el seu coneixement. En aquesta Tesi es considera com a fenomen responsable de l'acceleració de l'esllavissament l'efecte del calor a la banda de tall, la qual cosa indueix a la generació de pressió d'aigua i, per tant, a la reducció de la resistència friccional. Es defineixen les equacions del problema (balanç de massa i calor i equacions constitutives) a la banda de tall i s'integren juntament amb l'equació del moviment. Per tal de trobar criteris pràctics per a quantificar el risc d'acceleració degut al fenomen analitzat, s'ha obtingut una solució analítica pel cas d'esllavissaments plans sota les hipòtesis d'incompressibilitat de l'aigua, partícules sòlides i medi porós. La comparació entre la solució analítica i la numèrica (sense considerar les hipòtesis imposades en el desenvolupament analític), quan es varien els paràmetres més rellevants dins d'un rang raonable, indica que la solució analítica és suficientment precisa per a aplicacions pràctiques. El desenvolupament termo-hidro-mecànic presentat s'aplica al caso de l'esllavissament de Vaiont. En primer lloc s'explica la situació d'estabilitat prèvia a la ruptura introduint la resistència de la roca mobilitzada. L'anàlisi és coherent amb la informació disponible (geometries de l'esllavissament, resistència residual, propietats dels materials i assaigs de laboratori). Quan el mecanisme de generació de pressió d'aigua degut al calor que resulta del treball friccional s'inclou a l'anàlisi dinàmic del model de l'esllavissament de Vaiont, es prediu be l'alta velocitat observada. S'han realitzat anàlisis de sensibilitat i d'efecte escala tant pel cas d'esllavissament pla com per la geometria de Vaiont. S'han trobat tres paràmetres rellevants per explicar l'acceleració del moviment: l'amplada de la banda de tall, la seva permeabilitat i la seva rigidesa. De fet, la permeabilitat i l'amplada de la banda de tall estan directament relacionats donat que tots dos depenen de la granulometria del material. Els resultats obtinguts indiquen que la permeabilitat de la banda és el paràmetre clau. Un llindar de permeabilitat establert entre 10-8 i 10-10 m/s, marca la transició entre esllavissaments potencialment accelerats (quan la permeabilitat és baixa) i esllavissaments segurs (permeabilitats majors a 10-10 m/s). En cas d'esllavissaments de grans dimensions, combinacions crítiques de la permeabilitat i amplada de la banda de tall resulten en un increment substancial de la temperatura. Els alts valors que resulten dels càlculs (cents o milers de ºC) invaliden l'anàlisi aquí presentat. Fenòmens com l'evaporació o la fusió de la roca haurien de ser inclosos en aquests casos.


21/11/2012: Antonio Gens i Beatriz Valleján reben la George Stephenson Medal 2012
Antonio Gens, catedràtic del Departament, i Beatriz Valleján, estudiant de Doctorat d'Enginyeria del Terreny, han rebut la George Stephenson Gold Medal de la Institution of Civil Engineersblank_page (ICE) britànica. La Medalla George Stephenson va ser instituïda l’any 1881 i s’atorga anualment per una contribució destacada en l'àmbit de l'Enginyeria Civil. Aquest any 2012 ha estat concedida per l’article: “Hydromechanical behaviour of a heterogeneous compacted soil: experimental observations and modelling” escrit per A. Gens. B. Valleján, M. Sánchez, C. Imbert, M.V. Villar i M. Van Geet i publicat a la revista Geotechniqueblank_page. La medalla va ser lliurada pel President del ICE, Richard Coackley, en una cerimònia celebrada a Londres el passat 12 de Octubre. La citació diu: “The paper is an outstanding study of using bentonite powder and pellets as sealing material in nuclear waste disposal facilities, giving an improved understanding of the problems related to the coupled hydro-mechanical behaviour of nuclear waste repositories.”

21-23/11/2012: Premi W(H)YDOC 2012 atorgat a la Doctorand de la UPC Anna Ramon Tarragona
Els passats dies 21, 22 i 23 de novembre de 2012 es va celebrar el “4th International Workshop of Young Doctors in Geomechanics” (W(H)YDOC 2012) a París a l’École des Ponts Paris Tech (ENPC).
L’objectiu del workshop W(H)YDOC 2012 va ser reunir joves Doctors en Geotècnia i estudiants de doctorat d’últim any per presentar les recerques desenvolupades durant les seves tesis doctorals. El participants procedien d’universitats de Bèlgica, Brasil, República Xeca, França, Alemanya, Itàlia, Països Nòrdics, Polònia, Espanya, Suïssa, Suècia, Regne Unit i Estats Units. També van participar a les jornades reconeguts professors en Geotècnia. Les jornades pretenien afavorir intercanvis constructius sobre idees i resultats recents de recerca.
Per part del Departament d’Enginyeria del Terreny, Cartogràfica i Geofísica (DETCG) de la UPC, l’estudiant de doctorat Anna Ramon Tarragona va presentar el seu treball “Crystal growth under bridge foundations”. Aquest treball ha estat desenvolupat durant la seva tesi doctoral al DETCG, de la UPC i ha estat dirigit pel Professor Eduardo Alonso.
A la finalització del workshop es va donar el premi W(H)YDOC Prize a la millor presentació realitzada per un participant durant la present edició 2012. El premi va ser atorgat al treball presentat per l’estudiant de Doctorat Anna Ramon Tarragona del DETCG de la UPC.

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Nomenaments

16/02/2012: Xavier Sánchez renova el càrrec de director del departament ETCG

A la reunió del Consell del Departament d'Enginyeria del Terreny, Cartogràfica i Geofísica realitzada el dia 16 de febrer de 2012 es va efectuar la votació per a l'elecció de nou director. En aquesta votació Xavier Sánchez Vila ha estat escollit per un segon mandat de tres anys.

 

22/06/2012: Sebastià Olivella nou catedràtic de la UPC

En el concurs desenvolupat el dia 22 de Juny del 2011, el professor del nostre Departament, Sebastià Olivella, va guanyar la plaça de Catedràtic de la Universitat Politècnica de Catalunya.

 

03/10/2012: Sebastià Olivella, nou director de l'Escola de Camins de la UPC

El 3 d'octubre, el catedràtic Sebastià Olivella Pastallé ha estat nomenat director de l'Escola de Caminsblank_page, de la Universitat Politècnica de Catalunya - BarcelonaTech (UPC). Sebastià Olivella, que va guanyar les eleccions el passat mes de setembre, substitueix en el càrrec al catedràtic Antonio Huerta Cerezuela, que ha ha dirigit l’Escola des de març de 2007 fins l’actualitat.
Catedràtic del Departament d’Enginyeria del Terreny, Cartogràfica i Geofísica de la UPC des de l’any 2011, Sebastià Olivella es va titular com a enginyer de Camins, Canals i Ports el 1987 a la UPC, estudis que va realitzar a la mateixa Escola Tècnica Superior d'Enginyers de Camins, Canals i Ports de Barcelona (ETSECCPB), que ara dirigeix.
Un cop titulat, va treballar com a enginyer consultor durant tres anys i, a continuació, va obtenir el títol de Doctor en Enginyeria del Terreny per la UPC, l’any 1995.
Ha estat sotsdirector de l’ETSECCPB amb diversos equips directius, concretament sotsdirector de Recerca i Postgrau durant el mandat del seu antecessor, Antonio Huerta.
En l’àmbit docent, Sebastià Olivella era fins ara el responsable del Màster Universitari en Enginyeria del Terreny i Enginyeria Sísmica.
El seu camp de recerca en l’enginyeria del terreny se centra en la modelització numèrica de problemes acoblats termo-hidro-mecànics en medis geològics, com ara les roques salines, els sòls argilosos i les esculleres.
Ha participat en nombrosos projectes de recerca, ha publicat més de 50 articles a revistes científiques i més de 100 articles en actes de congressos. Ha estat reconegut amb diversos premis internacionals pels seus articles a publicacions científiques especialitzades, distincions entre les quals destaca la Geotechnical Research Medal que atorga la Institution of Civil Engineersblank_page de Londres (Regne Unit).
L’acte de presa de possessió ha tingut lloc a la sala d’actes de l’Escola de Camins, i ha comptat amb l'assistència del rector de la UPC; la secretària general de la Universitat, Ana Abelaira, i Antonio Huerta, fins ara director de l'Escola.


11/10/2012: Jean Vaunat nou responsable del Màster en Enginyeria del Terreny i Enginyeria Sísmica
La Junta del Departament d'Enginyeria del Terreny, Cartogràfica i Geofísica, en la sessió del dia 11 d'octubre de 2012 (acord JDE-12-4), ha nomenat a Jean Vaunat com a nou responsable del Màster en Enginyeria del Terreny i Enginyeria Sísmica en substitució de Sebastià Olivella, que ha estat nomenat Director de l'ETSECCPB.

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darrera modificació: Agost 2013
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