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En esta tesis se estudian los efectos ambientales de la producción del cemento, incluyendo las diferentes etapas que componen su ciclo de vida, con objeto de estructurar y proponer las bases fundamentales de un Inventario del Ciclo de Vida (ICV) nacional de dicho producto.Tras realizar un estudio sobre los ICV del cemento, existentes y disponibles en ámbito internacional, se analizan los límites aplicados a los diferentes subsistemas de producción y se estudia la viabilidad de utilización de estos ICV en el análisis del ciclo de vida (ACV) de los productos con base cemento. Este análisis se desarrolla a partir de un estudio comparativo de los datos de entradas y salidas de los distintos ICV de la producción de cemento disponibles, y demuestra la necesidad de estructurar los inventarios a través de distintos subsistemas de producción.A partir de lo anterior, se plantea un modelo de inventario del ciclo de vida del cemento aplicable a España o a cualquier otro país con la misma técnica productiva. Se aporta el concepto de memoria ambiental (MA), que permite utilizar el ACV desde distintos puntos de análisis (global, regional y local), con un tratamiento integrado de las diferentes prestaciones requeridas a un producto e incorporando otros efectos medioambientales que intervengan en los procesos de producción. Al mismo tiempo, este planteamiento permite realizar estudios por etapas (de la "cuna hasta la puerta" o de la "cuna hasta la tumba") y por distintos niveles de análisis. Esta metodología se aplica en el desarrollo del inventario de un cemento específico.Las conclusiones apuntan a la necesidad de elaborar un inventario nacional, representativo de la producción de cemento, como forma de garantizar una suficiente fiabilidad en los resultados de ACV de productos derivados del cemento. / In this thesis, the environmental effects of the Portland Cement Production, including its different life cycle stages, are studied. The main objective of the work is to structure and propose the fundamental bases of a national Life Cycle Inventory (LCI) of the portland cement.Taking into account the available data sets of the cement's LCI, the system's boundaries of different production systems are verified and the use of these LCI in the environmental Life Cycle Assessment (LCA) of portland cement products is analysed. The analysis is based on a comparative study of the inputs and outputs of the different available cement production LCIs. The results show that it is necessary to change the structure of these LCIs, mainly considering the process steps.Thereafter, a model of LCI applicable to cement produced in Spain or in another country with the same productive technique is presented. The concept of environmental memory (EM) is then introduced, allowing the use of the LCI according to different points of view, such as global, regional or local. It provides an integrated treatment of the different product performances, considering other environmental effects that are present in the production processes. The concept allows studying LCAs in different limit boundaries ("cradle to gate" or "cradle to grave") and different analysis levels. This methodology is applied in the development of the inventory of specific portland cement. The conclusions show that it is necessary to build a national inventory, which really represents the portland cement production as the only way to guarantee the reliability of the LCA results applied to portland cement products.

The objective of this thesis is to develop and evaluate a methodology for the solution of the Navier-Stokes equations for Bingham Herschel-Bulkley viscoplastic fluids using stabilized mixed velocity/pressure finite elements. The theoretical formulation is developed and implemented in a computer code. Numerical solutions for these viscoplastic flows are presented and assessed. Viscoplastic fluids are characterized by minimum shear stress called yield stress. Above this yield stress, the fluid is able to flow. Below this yield stress, the fluid behaves as a quasi-rigid body, with zero strain-rate. First, the Navier-Stokes equations for incompressible fluid and two immiscible fluids considering free surface are presented. A review of the Newtonian and non-Newtonian rheological models is included, with a detailed description of the viscoplastic models. The regularized viscoplastic models due to Papanastasiou are described. Double viscosity regularized models are proposed. The analytical solutions for parallel flows are deduced for Newtonian, Bingham, and Herschel-Bulkley, pseudoplastic and dilatant fluids. The discrete model is developed, and the Algebraic SubGrid Scale (ASGS) stabilization method, the Orthogonal Subgrid scale (OSS) method and the split orthogonal subscales method are introduced. For the cases of flows with a free surface, the simplified Eulerian method is employed, with the level set method to solve the motion of the free. A convergence study is performed to compare the ASGS and OSS stabilization methods in parallel flows with Bingham and Herschel-Bulkley fluids. The double viscosity regularized models show lower convergence error convergence than the regularized models used commonly. Numerical solutions developed in this thesis are applied to a broad set of benchmark problems. They can be divided into three groups: Bingham flows, Herschel-Bulkley flows and free surface flows. The solutions obtained validate the methodology proposed in this research and com-pare well with the analytical and numerical solutions, experimental and field data. The methodology proposed in this thesis provides a computational tool to study con-fined viscoplastic flows, common in industry, and debris viscoplastic flows with free surface. / El objetivo de esta tesis es formular y evaluar una metodología para la resolución de las ecuaciones de Navier-Stokes para los fluidos viscoplásticos de Bingham y de Herschel-Bulkley mediante el método de los elementos finitos mixtos estabilizados velocidad/presión. Se desarrolla una formulación teórica, se realiza la implementación computacional y se presentan y evalúan soluciones numéricas para estos fluidos viscoplásticos. Los fluidos viscoplásticos se caracterizan por presentar una tensión de corte mínima, denominada tensión de fluencia. Por encima de esta tensión de corte mínima el fluido comienza a moverse. En caso de no superarse esta tensión de fluencia, el fluido se comporta como un cuerpo rígido o quasi-rígido, con velocidad de deformación nula. Se presentan inicialmente las ecuaciones de Navier-Stokes para un fluido y dos fluidos incompresibles e inmiscibles considerando superficie libre. Se presenta una revisión de los modelos reológicos Newtonianos y los modelos no-Newtonianos. Se hace una descripción detallada de los modelos viscoplásticos. Se describen los modelos viscoplásticos regularizados de Papanastasiou. Se proponen modelos regualarizados de doble viscosidad como alternativa a los comúnmente usados. Se deducen las soluciones analítica en flujos paralelos para el fluido Newtoniano, el fluido de Bingham, de Herschel-Bulkley, el fluido pseudoplástico y dilatante. Se desarrolla el modelo discreto, así como la formulación estabilizada con los métodos de subescalas algebraica (Algebraic subgrid scale, ASGS), de subescalas ortogonales (Orthogonal subgrid scale, OSS) y de subescalas ortogonales con la presión y el termino convectivo desacoplados, split-OSS. En el caso del fluido con superficie libre se presenta el método euleriano simplificado, el cual usa el método de superficie de nivel level set para resolver el movimiento de esta superficie libre. Se presenta un estudio de convergencia con los métodos de estabilización OSS y ASGS en los flujos paralelos de Bingham y de Herschel-Bulkley. Los modelos regularizados de doble viscosidad muestran menor error de convergencia que los usados regularmente. Se presentan las soluciones numéricas desarrolladas en esta tesis para un amplio conjunto de problemas benchmark. Pueden dividirse en tres grupos: flujos de Bingham, flujos de Herschel-Bulkley y flujos con superficie libre. Las soluciones obtenidas validan la metodología propuesta en este trabajo de investigación comparándose muy bien con las soluciones analíticas, numéricas, con resultados experimentales y datos de campo. La metodología propuesta en esta tesis proporciona una herramienta computacional para estudiar flujos viscoplásticos confinados, muy comunes en la industria, y los flujos detríticos viscoplásticos con superficie libre.

La present tesi està dedicada a l'anàlisi d'una tècnica constructiva avui desapareguda del ventall de tecnologies utilitzades a 1'edificació a casa nostra: la tàpia.La justificació per a l'estudi d'una tècnica en desús pot venir avalada des de diferents camps de coneixement com a un exercici útil en si mateix per les conclusions que es puguin extreure encara que no siguin d'una aplicació inmediata.En aquest cas, però, dues visions concretes han revitalitzat l'interès d'estudiosos per les tècniques de construcció en terra com a tècniques alternatives a les usuals i han ocasionat un autèntic allau d'estudis, iniciatives, experiments i propostes que han remogut un ampli espectre de tècnics, universitats, organitzacions no gubernamental s i agències estatals.

En esta tesis se desarrolla una metodología general para la identificación de parámetros en problemas geotécnicos. Dado un problema especifico se supone fijado un modelo (determinista) y se consideran conocidos algunos valores de las variables de estado que caracterizan el sistema (observaciones). La identificación de parámetros o resolución del problema inverso consiste en estimar los parámetros del modelo que mejor ajustan predicciones y medidas. Como criterio de identificación se ha escogido el de máxima verosimilitud que permite incorporar en su formulación la información previa disponible sobre los parámetros a identificar. El problema matemático que resulta es el de minimización de una función objetivo que se resuelve numéricamente utilizando los algoritmos de Gauss-Newton y de Marquardt. Para ello se requiere calcular la matriz de derivadas de las variables medidas respecto de los parámetros calculo que se propone realizarlo utilizando el método de los elementos finitos indicando el procedimiento para ello tanto en modelos lineales como no lineales. Las matrices de covarianzas de los errores de las medidas que aparecen de modo natural en la formulación propuesta se calculan para diferentes tipos de instrumentos utilizados en la medida de desplazamientos en el terreno. Se desarrolla además una metodología para considerar la estructura de error como una variable mas a identificar. La metodología global propuesta se aplica a varios ejemplos teóricos referentes a excavación de túneles y a un caso real relativo a un túnel real en el que se midieron desplazamientos y se identificaron módulos de las capas de terreno afectadas por la excavación.

The objectives of this thesis are: the ex ante seismic risk evaluation for urban centers, the disaster risk management evaluation and the ex post risk evaluation of the damaged buildings after an earthquake. A complete review of the basic concepts and of the most important recent works performed in these fields. These aspects are basic for the development of the new ex ante and ex post seismic risk evaluation approaches which are proposed in this thesis and for the s evaluation of the effectiveness of the disaster risk management.Risk has been defined, for management purposes, as the potential economic, social and environmental consequences of hazardous events that may occur in a specified period of time. In Chapter 3 of this thesis, a multidisciplinary evaluation, that takes into account not only the expected physical damage, the number and type of casualties or economic losses, but also the conditions related to social fragility and lack of resilience, which favour the second order effects when a hazard event strikes an urban centre. The proposed general urban risk evaluation method is multi-hazard and holistic, that is, an integrated and comprehensive approach whose objective is to guide decision-making. This method has been applied to the cities of Bogota, Colombia, and Barcelona, Spain, and it is being applied to Metro Manila, Philippines.Chapter 4 develops a methodology for the disaster risk management evaluation. A disaster risk management index, DRMi, is conceptually supported and formulated, which measures the performance and the effectiveness of the risk management in a territory that can be a country, a subnational region or a city. The proposed DRMi is developed by quantifying four public policies: the risk identification, the risk reduction, the disaster management and the governance and financial protection. With this methodology eleven countries of Latin America and the Caribbean; Colombia at subnational level and Bogota at urban level were evaluated.In chapter 5 a methodology for the ex-post evaluation of the seismic damage is developed, using computational intelligence techniques. It has the objective of assisting non-expert professionals of building construction in evaluating the damage and safety of buildings after strong earthquakes, facilitating decision-making on their habitability and reparability during the emergency response phase. This neuro-fuzzy system has been adopted for its official use by the cities of Bogota and Manizales, in Colombia.The conclusions of this thesis are shown in Chapter 6, where also future lines of investigation are presented. The main conclusions are:- The proposed model for the holistic evaluation of the seismic risk facilitates the integral risk management and the decision making on risk reduction. The analysis of the results allows to establish priorities for the mitigation and actions of prevention and planning aiming to modify the conditions that influence on the risk of the zone.- The proposed disaster risk management index, DRMi, is consistent, methodical and has been developed to measure the risk management performance. This index allows to make the evaluation in a systematic and quantitative way and allows to define operation objectives and to improve the efficiency of the risk management. - A novel system of support to the habitability and damage evaluation of buildings, based on fuzzy logic and artificial neural networks was proposed. This kind of tool is useful due to the type of information that is handled, which is subjective and incomplete. Linguistic qualifications can appropriately be represented by fuzzy sets. An artificial neuronal network was used to calibrate the system starting from the experts judgment.Finally, several annexes are included which include details on methodological and calculation aspects related to the of proposed risk evaluation methods.

The characteristics of the compaction process condition the hydro-mechanical behaviour of soils imposing to them certain structure, a suction and an initial state of preconsolidation. Two of the aspects little studied in these soils are the effects of the anisotropy derived from the compaction process and the connection between the deformations and the humidity changes when they are under changes of suction or tension. In individual, it is to emphasize that in relation to these two aspects there exist until present few experimental results, specially in triaxial conditions.The primary objective of the Thesis has been to obtain useful guidelines of behaviour experimentally to develop conceptual constitutive models that cover the indicated aspects. For this, the hydro-mechanical behaviour of a statically compacted soil with an open fabric has been analyzed under controlled tension and suction paths having considered the stress history achieved out during the compaction. The secondary target, but necessary to reach the primary target, has been to construct and put to point a suction-controlled triaxial cell, automated. One of the most relevant aspects of the cell is the possibility to measuring sample deformations both local and global form.The tests have been performed on the one dimensionally compacted Barcelona clay. Characterization of the structure of compacted soil has performed by means of electronic microscopy (ESEM) and mercury intrusion porosimetry (MIP). The test procedures to put to point are described in detail in the text of the Thesis. In the tests, it has been observed that due to the soil deformation, the changes in the retention curve of the material lead to that an increase of soil water on loading under a low suction (10 kPa). In this loading path with higher suctions a reduction of water has been observed. The tests have shown that the initial yielding curve of the soil can be displayed as an inclined elliptical form and that during the initial phase of isotropic loading path is observed appreciable shear strain. The axis inclination of the ellipse shows similar features that the inclination of stress paths followed during the compaction in conditions of null lateral deformation. As increasing the applied load or reducing the suction, accumulating irreversible deformations, a progressive tendency towards isotropic behaviour of the soil has been observed. On the other hand, it has been observed that the relations between shear and volumetric plastic strain increment are similar when collapse paths by decrease, suction or increase loading are followed. The experimental results have been interpreted using as conceptual framework the Barcelona basic model, the model for saturated anisotropic soil of Wheeler et al. (2003) and the hydromechanical model of Vaunat et al. (2000).

Els objectius principals d’aquesta tesi són dos: d’una banda estudiar l’estructura de la variabilitat de la precipitació a diferents escales espacials i temporals, i de l’altra, estudiar l’estructura dels errors en les estimacions quantitatives de precipitació a través de radar. Pel que fa a l’estudi de l’estructura de la precipitació es proposa un marc de comparació per a mètodes de downscaling basat en valorar el grau amb què cada mètode és capaç de reproduir la variabilitat observada a les diferents escales de la pluja i la seva estructura multifractal. Finalment es proposa un mètode de downscaling tridimensional per a generar camps de precipitació d’alta resolució. Partint de dades mesurades amb radar, és capaç de reproduir la variabilitat a totes les escales de la pluja, i a la vegada, conservar l’estructura vertical de la precipitació observada pel radar. En aquesta tesi s’estudia també l’estructura dels errors associats a les mesures de radar, tant terrestre com embarcat en satèl·lit, que queden després de la cadena de correcció. Es realitza un estudi mitjançant simulació física de les observacions del radar, sobre un camp de precipitació d’alta resulució, per caracteritzar l’error relacionat amb la distància d’observació. També es caracteritza l’error total en les estimacions quantitatives de pluja dels radars terrestres mitjançant comparació contra un producte de referència basat en la combinació de radar i pluviòmetres. L’estructura de l’error trobada ha estat usada per generar un ensemble d’estimacions de pluja, que representa la incertesa en les estimacions, i pot ser emprat per aplicacions probabilístiques. Pel que fa a l’estudi de l’estructura de l’error associat a les estimacions de radar embarcat en satel·lit, s’han realitzat comparacions del radar embarcat en el satèl·lit TRMM contra equipament terrestre, per tal de caracteritzar, sota diverses condicions, les diferències en les mesures de precipitació. / The principal objectives of this thesis are two: on one hand study the structure of the precipitation’s variability at different spatial and temporal scales, and on the other hand study the structure of the errors in the quantitative precipitation estimates by radar. In relation to the precipitation structure, a comparison framework for downscaling methods is proposed. Within this framework, the capability of each method reproducing the variability and multifractal behaviour observed in rainfall can be tested. A three-dimensional downscaling method to generate high-resolution precipitation fields from radar observations is proposed. The method is capable to reproduce the variability of rainfall at all scales and, at the same time, preserve the vertical structure of precipitation observed by the radar. In this thesis the structure of the errors that remain after the correction chain in radar measurements (both ground- and space-borne) is also studied. Simulation of the radar physical measurement process over high-resolution precipitation fields is performed to characterize the error related with range. The overall error in quantitative precipitation estimates by radar is characterized through comparison of radar estimates with a reference product based on a radar-raingauges merging. The error structure is used to generate a radar ensemble of precipitation estimates that represents the uncertainty in the measurements and can be used in probabilistic applications. Regarding the study of the errors associated to spaceborne radar measurements, comparisons of TRMM Precipitation Radar with ground equipment are performed to characterize the discrepancies between the precipitation estimates under different conditions.

Occurrence of debris flows has received little attention in the Pyrenees, probably due to the small risk faced by most of the debris-flow prone sites in this mountain range. Nevertheless, the event of Biescas, which occurred in august 1996 and causing 87 casualties, demonstrates the existence of high-risk spots in the region and justifies the elaboration of the debris-flow hazard assessment presented in this thesis. Five debris flows, which occurred in 2008, are selected; and site-specific descriptions and analysis, regarding geology and morphology, were performed. The results are compared with worldwide data and some conclusions on hazard assessment are presented. The preliminary analysis of some major Eastern Pyrenean debris flows represents the background for this thesis. The necessity of possessing an inventory of past occurrences is of crucial importance when assessing debris-flow hazard. Criteria of reconnaissance were thought to be visible from aerial viewing. 691 tracks through which debris flows are thought to have travelled have been revealed. Based on debris-flow inventories and using a geographical information system, the debris-flow hazard assessment presented in this thesis takes into account fluvio-morphologic parameters, gathered for every 1st-order catchment as well as every 2nd-order catchment. Mountainous headwaters are a common subject in geomorphological studies. Often investigated at local scale, the geomorphological context in which headwaters evolve has been poorly reported in the Central-Eastern Pyrenees or worldwide. A series of parameters obtained for Central-Eastern Pyrenean headwaters catchments consisting of 3005 1st- and 655 2nd-order catchments are presented. Acquired from a digital elevation model, these catchments have been digitalised, identified and attributed a value for each parameter. Previously reported parameters¿ ranges agree with those presented in this study. For the first time, the ranges of values give details about the Central-Eastern Pyrenees headwater catchments. Data mining techniques are used on the morphometric parameters, to calculate and test three different models. The first model is a logistic regression. The other two are classification trees, which are rather novel susceptibility models associated with debris flows. Results related to the training dataset show that the optimized model¿s performance lies within existing reported range although closer to the lowest end (near 70%). When the models are applied to the test set, the logistic regression seems to offer the best prediction, as training and test set results are very similar in terms of performance. Trees are better at extracting laws from a training set, but validation through a test set gives poorer results for a prediction at regional scale. The determination of magnitude of a historic event can be done by distinguishing its deposits. However this is not a trivial task in debris fans that accumulate deposits, corresponding to consecutive debris flows, especially if only a conventional geomorphological analysis is carried out. The event deposits can be mapped and, subsequently, trees damaged by the flows sampled for dating events. A magnitude-frequency relationship was prepared for El Rebaixader site, at local scale, and is compared to that of the Tordó creek. Moreover, a debris-flow inventory was created in the "Aigüestortes i Estany de Sant Maurici" National Park in the Central Pyrenees, Spain, and this regional magnitude-frequency relationship is compared to that of Rebaixader. Both curves include a strong rollover effect at about 2000 m2, and events larger than this magnitude can be represented by a power law, with an exponent between -1.5 and -1.9. This thesis is a first step toward the assessment of debris-flow hazard in the Central-Eastern Pyrenees. Although a lot of information is provided, more work is still to be done, in order to fully capture debris-flow importance in landscape evolution.

DE TESIS DOCTORALEsta investigación, surge por la necesidad de incluir los sistemas de acondicionamiento ambiental natural y el diseño energético pasivo en el proyecto arquitectónico en la ecología del desierto de Atacama, Chile. Por ello, la finalidad es describir y desvelar las causas de la involución del proceso de transición energética y de transformación ambiental realizada por los usuarios de las viviendas del conjunto habitacional Salar del Carmen; ubicado en la ciudad de Antofagasta. El proceso regresión ha significado en el ámbito socio-cultural la desaparición de una cultura solar y en el ámbito formal-espacial la pérdida del sentido del "habitar el desierto". A pesar de ello, en la arquitectura informal descubrimos que el proceso de adaptación al clima revela una fuerte identidad ambiental en lo referente a la arquitectura del paisaje y a la relación de los edificios con el entorno ecológico desértico. En la primera parte se desarrolla el tema de la transición energética de la arquitectura hacia las energías renovables. La evidente y creciente ponderación de los problemas ambientales ante las señales de degradación de los ecosistemas de la Tierra, producto de un desarrollo insostenible, han conducido a un profundo cuestionamiento de los modelos de crecimiento de la sociedad actual, disponiéndola en la urgente necesidad de realizar una proceso de "transición hacia una cultura ambiental", basado en las energías renovables.La segunda parte se centra en el análisis de la relación ecología y desierto. En la actualidad más del 15% de la población mundial habita en áreas desérticas. Esto demuestra la importancia de definir actitudes y diferenciar las formas de vida de zonas no desérticas. Las zonas áridas requieren de un planteamiento diferente al actual, no es utópico plantear un modelo de desarrollo basado en energéticos renovables. En la tercera parte se analiza la relación de la arquitectura y el desierto, a partir de la interpretación del espacio desértico como espacio de modernidad, y como una manifestación que vincula a la obra su paisaje estableciendo una interacción constante y referida a los aspectos térmicos y lumínicos del espacio arquitectónico, expresados como modelos de sostenibilidad. En la cuarta parte se presenta el caso de estudio, se analiza el proceso de transformación y acondicionamiento ambiental de las viviendas realizadas por sus habitantes. A través de una selección de las diversas tipologías de viviendas, de acuerdo al número de casos existentes, su emplazamiento y ubicación en la parcela, comprendiendo casos de viviendas transformadas y no transformadas. Por otro lado, se proponen tres instrumentos para la recogida de datos: observación directa, encuesta de confort y registro de parámetros ambientales con instrumentos. La observación de este proceso nos permitió percatarnos de la distancia existente entre las necesidades de los usuarios y los programas arquitectónicos. Pero sobre todo, la observación nos ratificó la pertinencia y propiedad de las acciones de acondicionamiento ambiental de las viviendas.Finalmente, las propuestas estratégicas de la presente investigación se centran en las invariantes como habitar la exterioridad, construir la sombra y habitar la penumbra como elementos singulares para que este proceso de transición de base energética sea realmente factible y exitoso.