94 research outputs found

    Assessing the potential for suffusion in sands using x-ray micro-CT images

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    Internal erosion is a major safety concern for embankment dams and flood embankments and is the focus of much research internationally. Suffusion is a mechanism of internal erosion which affects gap-graded or broadly graded cohesionless soils and is characterised by selective removal of fine material, leaving behind a coarse material with increased hydraulic conductivity. Early studies on suffusion proposed design criteria based on laboratory testing, and presented conceptual models to explain the results in terms of grain-scale behaviour. The study by Kenney & Lau (1985) identified three criteria for suffusion: 1 – Fine particles must be free to move (mechanical criterion); 2 – Fine particles must be small enough to fit through the void space between coarse particles (geometric criterion); 3 – Fluid flowing through the void space must have sufficient velocity to transport the fine particles (hydraulic criterion). Recent studies have examined the first two criteria using grain-scale models with idealised particles, including analytical models and discrete element models (DEM) with circular or spherical particles. This thesis presents a new methodology, using non-destructive 3D imaging (micro-CT) to characterise the internal microstructure in physical specimens of sands and glass beads. This methodology involved the development of innovative image processing and numerical techniques to quantify unstable particle assemblies and to measure particle size distributions and void constriction size distributions. The new method was validated and was shown to produce good agreement with existing methods for idealised particle configurations, however the results for real sand specimens provided new insights into the effects of particle shape, particle size distribution and density on void constriction sizes. Furthermore, the 3D images of real specimens have provided new insights into the appropriateness of existing conceptual models for gap-graded particle structures. These results were used to critically examine and evaluate existing mechanical and geometric criteria for suffusion. The 3D images showed, qualitatively, that the void structures in sands varied significantly from those in porous rocks – which had been the basis for the majority of existing grain-scale fluid flow models. To examine this issue quantitatively, computational fluid dynamics (CFD) simulations were performed within the 3D images of sands and glass beads, in parallel to laboratory permeameter tests on the same materials. The results presented in this thesis provided entirely new insights into the patterns of fluid flow in sands, they allowed correlations to be made between fluid flow and void constriction sizes and also showed how local velocities varied from volume-average discharge and seepage velocities. This study provides new information to support, clarify and improve upon the current understanding of suffusion, filtration and seepage flows in sands. The detailed methodology and results also highlight issues of great importance to future micro-scale modelling of these phenomena.Open Acces

    A CAD/CAM concept for High Speed Cutting compatible rough machining in die, mould and pattern manufacturing

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    Die, mould and pattern manufacturing plays a central role in the production of capital and consumer goods. Ever-shorter product life cycles and the expanding diversity of features require continued cuts in production lead times. Recently, these developments in the market, accompanied by a simultaneous demand for improved quality at a lower cost, are becoming clearly noticeable. Along with the streamlining of organizational structures and advanced technological developments, it is above all the introduction of CAD/CAM software that offers great potential for reducing lead times for components with free surfaces. The role of milling in the integrated process chain of die, mould and pattern manufacturing is steadily gaining importance. This is due to the ongoing further development of milling-machine technology, the cutting tools and their coatings, and of the CAD /CAM systems themselves. Generally speaking, the milling process is divided into the operations of roughing and finishing. For rough milling, efficient machining means high stock-removal rates together with close contour approximation and low tool wear. Rough milling is normally carried out layer by layer, i.e. in a 2.SD machining operation with constant depth per cut because the rate of material removal and process reliability are usually highest when this method is used. High-speed cutting (HSC), which has been the subject of extensive university research for far more than ten years, has meanwhile become established as a finishing process in many companies. However, the application of HSC demands the observance of geometric and, above all, technological constraints. A considerable degree of optimization can be achieved when these constraints are applied to rough milling. In the integrated process chain, the CAD/CAM system performs the task of calculating NC programs based on CAD data which meet the requirements posed by rough and finish machining operations. While general interest was focused on the development of CAM strategies for HSC finish machining, advanced development of technology-oriented CAM modules for upstream roughing operations was neglected. The paper at hand deals with the development of a CAM module for rough-machining complex components in die, mould and pattern manufacturing. It provides an insight into the process-technological demands made on HSC operations and their application in rough machining, from which guidelines and requirements on technologically oriented NC functions for CAM software were derived. These encompass both the complete development of an interactive, dialogue-based user guidance function and the algorithmic conversion of the calculation routines. The concept at hand was almost entirely implemented and integrated in the CAD/CAM system developed by Tebis AG, Germany, which was conceived especially for die, mould and pattern manufacturing and is scheduled for introduction to the free market starting in April 2001

    X-Ray imaging applied to the characterization of polymer foam's cellular structure and its evolution

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    Las espumas poliméricas son materiales celulares que poseen una fase sólida continua y otra gaseosa bien discontinua (celda cerrada) o continua (celda abierta). Habitualmente estas estructuras se describen mediante parámetros macroscópicos como la densidad relativa y otros microscópicos como el tamaño de celda o la densidad de celdas. Además, estos materiales poseen características peculiares como anisotropía, orientación de los poros y tortuosidad que les proporcionan propiedades físicas singulares. Convencionalmente el estudio de las espumas poliméricas se realiza mediante el análisis de la estructura celular final obtenida. Ello se debe principalmente a que es complicado detener el proceso de expansión una vez se ha iniciado. Debido a esto los estadios intermedios durante los procesos de espumado no son accesibles, es decir, no se obtiene información acerca de los mecanismos que generan la estructura final. Estos mecanismos físico-químicos fundamentales que gobiernan la generación y evolución de la estructura celular durante el espumado son la nucleación y el crecimiento. Por el contrario, existen otros mecanismos que son responsables de la degeneración de la estructura celular son el drenaje, la coalescencia y el coarsening. Los inconvenientes que existen para abordar el estudio de estos mecanismos durante el proceso de espumado, junto con las peculiaridades de estos sistemas hacen que las técnicas de imagen mediante rayos X sean una herramienta extraordinaria para el estudio in-situ de la evolución de la estructura celular y los mecanismos de espumado. Además, de manera complementaria, la imagen mediante rayos X permite la obtención de tomogramas para el estudio de la estructura celular en el estado final. Incluso es posible llegar más lejos gracias a los últimos desarrollos en tomografía rápida. Esta técnica es capaz de estudiar en 3D la evolución de la estructura celular en el tiempo. Uno de los requisitos esenciales para el estudio de las espumas poliméricas mediante la imagen con rayos X y que condiciona su aplicabilidad es la correcta selección de los componentes y el diseño del equipo de imagen. Esto se debe principalmente a características intrínsecas a las espumas poliméricas: baja absorción de los rayos X, espesores reducidos, estructura de celdas en el rango micrométrico, rápida evolución durante su fabricación y otras peculiaridades morfológicas de su estructura.Departamento de Física de la Materia Condensada, Cristalografía y Minerealogí

    Sketching-based Skeleton Extraction

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    Articulated character animation can be performed by manually creating and rigging a skeleton into an unfolded 3D mesh model. Such tasks are not trivial, as they require a substantial amount of training and practice. Although methods have been proposed to help automatic extraction of skeleton structure, they may not guarantee that the resulting skeleton can help to produce animations according to user manipulation. We present a sketching-based skeleton extraction method to create a user desired skeleton structure which is used in 3D model animation. This method takes user sketching as an input, and based on the mesh segmentation result of a 3D mesh model, generates a skeleton for articulated character animation. In our system, we assume that a user will properly sketch bones by roughly following the mesh model structure. The user is expected to sketch independently on different regions of a mesh model for creating separate bones. For each sketched stroke, we project it into the mesh model so that it becomes the medial axis of its corresponding mesh model region from the current viewer perspective. We call this projected stroke a “sketched bone”. After pre-processing user sketched bones, we cluster them into groups. This process is critical as user sketching can be done from any orientation of a mesh model. To specify the topology feature for different mesh parts, a user can sketch strokes from different orientations of a mesh model, as there may be duplicate strokes from different orientations for the same mesh part. We need a clustering process to merge similar sketched bones into one bone, which we call a “reference bone”. The clustering process is based on three criteria: orientation, overlapping and locality. Given the reference bones as the input, we adopt a mesh segmentation process to assist our skeleton extraction method. To be specific, we apply the reference bones and the seed triangles to segment the input mesh model into meaningful segments using a multiple-region growing mechanism. The seed triangles, which are collected from the reference bones, are used as the initial seeds in the mesh segmentation process. We have designed a new segmentation metric [1] to form a better segmentation criterion. Then we compute the Level Set Diagrams (LSDs) on each mesh part to extract bones and joints. To construct the final skeleton, we connect bones extracted from all mesh parts together into a single structure. There are three major steps involved: optimizing and smoothing bones, generating joints and forming the skeleton structure. After constructing the skeleton model, we have proposed a new method, which utilizes the Linear Blend Skinning (LBS) technique and the Laplacian mesh deformation technique together to perform skeleton-driven animation. Traditional LBS techniques may have self-intersection problem in regions around segmentation boundaries. Laplacian mesh deformation can preserve the local surface details, which can eliminate the self-intersection problem. In this case, we make use of LBS result as the positional constraint to perform a Laplacian mesh deformation. By using the Laplacian mesh deformation method, we maintain the surface details in segmentation boundary regions. This thesis outlines a novel approach to construct a 3D skeleton model interactively, which can also be used in 3D animation and 3D model matching area. The work is motivated by the observation that either most of the existing automatic skeleton extraction methods lack well-positioned joints specification or the manually generated methods require too much professional training to create a good skeleton structure. We dedicate a novel approach to create 3D model skeleton based on user sketching which specifies articulated skeleton with joints. The experimental results show that our method can produce better skeletons in terms of joint positions and topological structure

    RHEOLOGY AND DYNAMICS OF CAPILLARY FOAMS AND THEIR APPLICATION TO ENHANCED OIL RECOVERY

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    Aqueous foams are ubiquitous; they appear in many products and processes and provide a variety of functional and sensory benefits to many applications because of their elastic and viscous rheological properties. In enhanced oil recovery, for example, foams can provide uniform displacement of oil that is trapped in underground reservoirs by blocking large pores, reducing gas mobility, and preventing viscous fingering. The recently discovered capillary foams, known for their stability, tunability, and oil-tolerance, are promising for enhanced oil recovery where the lifespan and functional rheological benefits of traditional foams are limited by contact with crude oil. The unique architecture of capillary foams, containing oil-coated bubbles and a network of oil-bridged particles, is however expected to affect foam rheology. In this work, the rheological properties of capillary foams were investigated and shown to be similar to but better tunable than those of surfactant foams because of the influence of the oil-particle network. The stability of flowing capillary foams was also found to be remarkable because the particle network mitigates foam collapse under stress. Finally, the feasibility of using capillary foams in enhanced oil recovery was evaluated in displacement experiments where capillary foams were found to achieve a higher sweep efficiency, than water alone, in displacing crude oil from a porous micromodel. The findings of this work provide an understanding of the underlying physics governing capillary foam rheology, define methods for tuning capillary foam rheology for applications in products and processes and serve as a starting point for optimizing capillary foam flooding for oil displacement from underground reservoirs.Ph.D

    Simulation of pore-scale flow using finite element-methods

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    I present a new finite element (FE) simulation method to simulate pore-scale flow. Within the pore-space, I solve a simplified form of the incompressible Navier-Stoke’s equation, yielding the velocity field in a two-step solution approach. First, Poisson’s equation is solved with homogeneous boundary conditions, and then the pore pressure is computed and the velocity field obtained for no slip conditions at the grain boundaries. From the computed velocity field I estimate the effective permeability of porous media samples characterized by thin section micrographs, micro-CT scans and synthetically generated grain packings. This two-step process is much simpler than solving the full Navier Stokes equation and therefore provides the opportunity to study pore geometries with hundreds of thousands of pores in a computationally more cost effective manner than solving the full Navier-Stoke’s equation. My numerical model is verified with an analytical solution and validated on samples whose permeabilities and porosities had been measured in laboratory experiments (Akanji and Matthai, 2010). Comparisons were also made with Stokes solver, published experimental, approximate and exact permeability data. Starting with a numerically constructed synthetic grain packings, I also investigated the extent to which the details of pore micro-structure affect the hydraulic permeability (Garcia et al., 2009). I then estimate the hydraulic anisotropy of unconsolidated granular packings. With the future aim to simulate multiphase flow within the pore-space, I also compute the radii and derive capillary pressure from the Young-Laplace equation (Akanji and Matthai,2010

    Tangent-ball techniques for shape processing

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    Shape processing defines a set of theoretical and algorithmic tools for creating, measuring and modifying digital representations of shapes.  Such tools are of paramount importance to many disciplines of computer graphics, including modeling, animation, visualization, and image processing.  Many applications of shape processing can be found in the entertainment and medical industries. In an attempt to improve upon many previous shape processing techniques, the present thesis explores the theoretical and algorithmic aspects of a difference measure, which involves fitting a ball (disk in 2D and sphere in 3D) so that it has at least one tangential contact with each shape and the ball interior is disjoint from both shapes. We propose a set of ball-based operators and discuss their properties, implementations, and applications.  We divide the group of ball-based operations into unary and binary as follows: Unary operators include: * Identifying details (sharp, salient features, constrictions) * Smoothing shapes by removing such details, replacing them by fillets and roundings * Segmentation (recognition, abstract modelization via centerline and radius variation) of tubular structures Binary operators include: * Measuring the local discrepancy between two shapes * Computing the average of two shapes * Computing point-to-point correspondence between two shapes * Computing circular trajectories between corresponding points that meet both shapes at right angles * Using these trajectories to support smooth morphing (inbetweening) * Using a curve morph to construct surfaces that interpolate between contours on consecutive slices The technical contributions of this thesis focus on the implementation of these tangent-ball operators and their usefulness in applications of shape processing. We show specific applications in the areas of animation and computer-aided medical diagnosis.  These algorithms are simple to implement, mathematically elegant, and fast to execute.Ph.D.Committee Chair: Jarek Rossignac; Committee Member: Greg Slabaugh; Committee Member: Greg Turk; Committee Member: Karen Liu; Committee Member: Maryann Simmon

    Methodology for high resolution spatial analysis of the physical flood susceptibility of buildings in large river floodplains

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    The impacts of floods on buildings in urban areas are increasing due to the intensification of extreme weather events, unplanned or uncontrolled settlements and the rising vulnerability of assets. There are some approaches available for assessing the flood damage to buildings and critical infrastructure. To this point, however, it is extremely difficult to adapt these methods widely, due to the lack of high resolution classification and characterisation approaches for built structures. To overcome this obstacle, this work presents: first, a conceptual framework for understanding the physical flood vulnerability and the physical flood susceptibility of buildings, second, a methodological framework for the combination of methods and tools for a large-scale and high-resolution analysis and third, the testing of the methodology in three pilot sites with different development conditions. The conceptual framework narrows down an understanding of flood vulnerability, physical flood vulnerability and physical flood susceptibility and its relation to social and economic vulnerabilities. It describes the key features causing the physical flood susceptibility of buildings as a component of the vulnerability. The methodological framework comprises three modules: (i) methods for setting up a building topology, (ii) methods for assessing the susceptibility of representative buildings of each building type and (iii) the integration of the two modules with technological tools. The first module on the building typology is based on a classification of remote sensing data and GIS analysis involving seven building parameters, which appeared to be relevant for a classification of buildings regarding potential flood impacts. The outcome is a building taxonomic approach. A subsequent identification of representative buildings is based on statistical analyses and membership functions. The second module on the building susceptibility for representative buildings bears on the derivation of depth-physical impact functions. It relates the principal building components, including their heights, dimensions and materials, to the damage from different water levels. The material’s susceptibility is estimated based on international studies on the resistance of building materials and a fuzzy expert analysis. Then depth-physical impact functions are calculated referring to the principal components of the buildings which can be affected by different water levels. Hereby, depth-physical impact functions are seen as a means for the interrelation between the water level and the physical impacts. The third module provides the tools for implementing the methodology. This tool compresses the architecture for feeding the required data on the buildings with their relations to the building typology and the building-type specific depth-physical impact function supporting the automatic process. The methodology is tested in three flood plains pilot sites: (i) in the settlement of the Barrio Sur in Magangué and (ii) in the settlement of La Peña in Cicuco located on the flood plain of Magdalena River, Colombia and (iii) in a settlement of the city of Dresden, located on the Elbe River, Germany. The testing of the methodology covers the description of data availability and accuracy, the steps for deriving the depth-physical impact functions of representative buildings and the final display of the spatial distribution of the physical flood susceptibility. The discussion analyses what are the contributions of this work evaluating the findings of the methodology’s testing with the dissertation goals. The conclusions of the work show the contributions and limitations of the research in terms of methodological and empirical advancements and the general applicability in flood risk management.:1 INTRODUCTION 1 1.1 Background 1 1.2 State of the art 2 1.3 Problem statement 6 1.4 Objectives 6 1.5 Approach and outline 6 2 CONCEPTUAL FRAMEWORK 9 2.1 Flood vulnerability 10 2.2 Physical flood vulnerability 12 2.3 Physical flood susceptibility 14 3 METHODOLOGICAL FRAMEWORK 23 3.1 Module 1: Building taxonomy for settlements 24 3.1.1 Extraction of building features 24 3.1.2 Derivation of building parameters for setting up a building taxonomy 38 3.1.3 Selection of representative buildings for a building susceptibility assessment 51 3.2 Module 2: Physical susceptibility of representative buildings 57 3.2.1 Identification of building components 57 3.2.2 Qualification of building material susceptibility 62 3.2.3 Derivation of a depth-physical impact function 71 3.3 Module 3: Technological integration 77 3.3.1 Combination of the depth-physical impact function with the building taxonomic code 77 3.3.2 Tools supporting the physical susceptibility analysis 78 3.3.3 The users and their requirements 79 4 RESULTS OF THE METHODOLOGY TESTING 83 4.1 Pilot site “Kleinzschachwitz” – Dresden, Germany – Elbe River 83 4.1.1 Module 1: Building taxonomy – “Kleinzschachwitz” 85 4.1.2 Module 2: Physical susceptibility of representative buildings – “Kleinzschachwitz” 97 4.1.3 Module 3: Technological integration – “Kleinzschachwitz” 103 4.2 Pilot site “La Peña” – Cicuco, Colombia – Magdalena River 107 4.2.1 Module 1: Building taxonomy – “La Peña” 108 4.2.2 Module 2: Physical susceptibility of representative buildings – “La Peña” 121 4.2.3 Module 3: Technological integration– “La Peña” 129 4.3 Pilot site “Barrio Sur” – Magangué, Colombia – Magdalena River 133 4.3.1 Module 1: Building taxonomy – “Barrio Sur” 133 4.3.2 Module 2: Physical susceptibility of representative buildings – “Barrio Sur” 141 4.3.3 Module 3: Technological integration – “Barrio Sur” 147 4.4 Empirical findings 151 4.4.1 Empirical findings of Module 1 151 4.4.2 Empirical findings of Module 2 155 4.4.3 Empirical findings of Module 3 157 4.4.4 Guidance of the methodology 157 5 DISCUSSION 161 5.1 Discussion on the conceptual framework 161 5.2 Discussion on the methodological framework 161 5.2.1 Discussion on Module 1: the building taxonomic approach 162 5.2.2 Discussion on Module 2: the depth-physical impact function 164 6 CONCLUSIONS AND OUTLOOK 167 6.1 Conclusions 167 6.2 Outlook 168 REFERENCES 171 INDEX OF FIGURES 199 INDEX OF TABLES 201 APPENDICES 203In vielen Städten nehmen die Auswirkungen von Hochwasser auf Gebäude aufgrund immer extremerer Wetterereignisse, unkontrollierbarer Siedlungsbauten und der steigenden Vulnerabilität von Besitztümern stetig zu. Es existieren zwar bereits Ansätze zur Beurteilung von Wasserschäden an Gebäuden und Infrastrukturknotenpunkten. Doch ist es bisher schwierig, diese Methoden großräumig anzuwenden, da es an einer präzisen Klassifizierung und Charakterisierung von Gebäuden und anderen baulichen Anlagen fehlt. Zu diesem Zweck sollen in dieser Arbeit erstens ein Konzept für ein genaueres Verständnis der physischen Vulnerabilität von Gebäuden gegenüber Hochwasser dargelegt, zweitens ein methodisches Verfahren zur Kombination der bestehenden Methoden und Hilfsmittel mit dem Ziel einer großräumigen und hochauflösenden Analyse erarbeitet und drittens diese Methode an drei Pilotstandorten mit unterschiedlichem Ausbauzustand erprobt werden. Die Rahmenbedingungen des Konzepts grenzen die Begriffe der Vulnerabilität, der physischen Vulnerabilität und der physischen Anfälligkeit gegenüber Hochwasser ein und erörtern deren Beziehung zur sozialen und ökonomischen Vulnerabilität. Es werden die Merkmale der physischen Anfälligkeit von Gebäuden gegenüber Hochwasser als Bestandteil der Vulnerabilität definiert. Das methodische Verfahren umfasst drei Module: (i) Methoden zur Erstellung einer Gebäudetypologie, (ii) Methoden zur Bewertung der Anfälligkeit repräsentativer Gebäude jedes Gebäudetyps und (iii) die Kombination der beiden Module mit Hilfe technologischer Hilfsmittel. Das erste Modul zur Gebäudetypologie basiert auf der Klassifizierung von Fernerkundungsdaten und GIS-Analysen anhand von sieben Gebäudeparametern, die sich für die Klassifizierung von Gebäuden bezüglich ihres Risikopotenzials bei Hochwasser als wichtig erweisen. Daraus ergibt sich ein Ansatz zur Gebäudeklassifizierung. Die anschließende Ermittlung repräsentativer Gebäude beruht auf statistischen Analysen und Zugehörigkeitsfunktionen. Das zweite Modul zur Anfälligkeit repräsentativer Gebäude beruht auf der Ableitung von Funktion von Wasserstand und physischer Einwirkung. Es setzt die relevanten Gebäudemerkmale, darunter Höhe, Maße und Materialien, in Beziehung zum erwartbaren Schaden bei unterschiedlichen Wasserständen. Die Materialanfälligkeit wird aufgrund internationaler Studien zur Festigkeit von Baustoffen sowie durch Anwendung eines Fuzzy-Logic-Expertensystems eingeschätzt. Anschließend werden Wasserstand-Schaden-Funktionen unter Einbeziehung der Hauptgebäudekomponenten berechnet, die durch unterschiedliche Wasserstände in Mitleidenschaft gezogen werden können. Funktion von Wasserstand und physischer Einwirkung dienen hier dazu, den jeweiligen Wasserstand und die physischen Auswirkung in Beziehung zueinander zu setzen. Das dritte Modul stellt die zur Umsetzung der Methoden notwendigen Hilfsmittel vor. Zur Unterstützung des automatisierten Verfahrens dienen Hilfsmittel, die die Gebäudetypologie mit der Funktion von Wasserstand und physischer Einwirkung für Gebäude in Hochwassergebieten kombinieren. Die Methoden wurden anschließend in drei hochwassergefährdeten Pilotstandorten getestet: (i) in den Siedlungsgebieten von Barrio Sur in Magangué und (ii) von La Pena in Cicuco, zwei Überschwemmungsgebiete des Magdalenas in Kolumbien, und (iii) im Stadtgebiet von Dresden, das an der Elbe liegt. Das Testverfahren umfasst die Beschreibung der Datenverfügbarkeit und genauigkeit, die einzelnen Schritte zur Analyse der. Funktion von Wasserstand und physischer Einwirkung repräsentativer Gebäude sowie die Darstellung der räumlichen Verteilung der physischen Anfälligkeit für Hochwasser. In der Diskussion wird der Beitrag dieser Arbeit zur Beurteilung der Erkenntnisse der getesteten Methoden anhand der Ziele dieser Dissertation analysiert. Die Folgerungen beleuchten abschließend die Fortschritte und auch Grenzen der Forschung hinsichtlich methodischer und empirischer Entwicklungen sowie deren allgemeine Anwendbarkeit im Bereich des Hochwasserschutzes.:1 INTRODUCTION 1 1.1 Background 1 1.2 State of the art 2 1.3 Problem statement 6 1.4 Objectives 6 1.5 Approach and outline 6 2 CONCEPTUAL FRAMEWORK 9 2.1 Flood vulnerability 10 2.2 Physical flood vulnerability 12 2.3 Physical flood susceptibility 14 3 METHODOLOGICAL FRAMEWORK 23 3.1 Module 1: Building taxonomy for settlements 24 3.1.1 Extraction of building features 24 3.1.2 Derivation of building parameters for setting up a building taxonomy 38 3.1.3 Selection of representative buildings for a building susceptibility assessment 51 3.2 Module 2: Physical susceptibility of representative buildings 57 3.2.1 Identification of building components 57 3.2.2 Qualification of building material susceptibility 62 3.2.3 Derivation of a depth-physical impact function 71 3.3 Module 3: Technological integration 77 3.3.1 Combination of the depth-physical impact function with the building taxonomic code 77 3.3.2 Tools supporting the physical susceptibility analysis 78 3.3.3 The users and their requirements 79 4 RESULTS OF THE METHODOLOGY TESTING 83 4.1 Pilot site “Kleinzschachwitz” – Dresden, Germany – Elbe River 83 4.1.1 Module 1: Building taxonomy – “Kleinzschachwitz” 85 4.1.2 Module 2: Physical susceptibility of representative buildings – “Kleinzschachwitz” 97 4.1.3 Module 3: Technological integration – “Kleinzschachwitz” 103 4.2 Pilot site “La Peña” – Cicuco, Colombia – Magdalena River 107 4.2.1 Module 1: Building taxonomy – “La Peña” 108 4.2.2 Module 2: Physical susceptibility of representative buildings – “La Peña” 121 4.2.3 Module 3: Technological integration– “La Peña” 129 4.3 Pilot site “Barrio Sur” – Magangué, Colombia – Magdalena River 133 4.3.1 Module 1: Building taxonomy – “Barrio Sur” 133 4.3.2 Module 2: Physical susceptibility of representative buildings – “Barrio Sur” 141 4.3.3 Module 3: Technological integration – “Barrio Sur” 147 4.4 Empirical findings 151 4.4.1 Empirical findings of Module 1 151 4.4.2 Empirical findings of Module 2 155 4.4.3 Empirical findings of Module 3 157 4.4.4 Guidance of the methodology 157 5 DISCUSSION 161 5.1 Discussion on the conceptual framework 161 5.2 Discussion on the methodological framework 161 5.2.1 Discussion on Module 1: the building taxonomic approach 162 5.2.2 Discussion on Module 2: the depth-physical impact function 164 6 CONCLUSIONS AND OUTLOOK 167 6.1 Conclusions 167 6.2 Outlook 168 REFERENCES 171 INDEX OF FIGURES 199 INDEX OF TABLES 201 APPENDICES 203El impacto de las inundaciones sobre los edificios en zonas urbanas es cada vez mayor debido a la intensificación de los fenómenos meteorológicos extremos, asentamientos no controlados o no planificados y su creciente vulnerabilidad. Hay métodos disponibles para evaluar los daños por inundación en edificios e infraestructuras críticas. Sin embargo, es muy difícil implementar estos métodos sistemáticamente en grandes áreas debido a la falta de clasificación y caracterización de estructuras construidas en resoluciones detalladas. Para superar este obstáculo, este trabajo se enfoca, en primer lugar, en desarrollar un marco conceptual para comprender la vulnerabilidad y susceptibilidad física de edificios por inudaciones, en segundo lugar, en desarrollar un marco metodológico para la combinación de los métodos y herramientas para una análisis de alta resolución y en tercer lugar, la prueba de la metodología en tres sitios experimentales, con distintas condiciones de desarrollo. El marco conceptual se enfoca en comprender la vulnerabilidad y susceptibility de las edificaciones frente a inundaciones, y su relación con la vulnerabilidad social y económica. En él se describen las principales características físicas de la susceptibilidad de edificicaiones como un componente de la vulnerabilidad. El marco metodológico consta de tres módulos: (i) métodos para la derivación de topología de construcciones, (ii) métodos para evaluar la susceptibilidad de edificios representativos y (iii) la integración de los dos módulos a través herramientas tecnológicas. El primer módulo de topología de construcciones se basa en una clasificación de datos de sensoramiento rémoto y procesamiento SIG para la extracción de siete parámetros de las edficaciones. Este módulo parece ser aplicable para una clasificación de los edificios en relación con los posibles impactos de las inundaciones. El resultado es una taxonomía de las edificaciones y una posterior identificación de edificios representativos que se basa en análisis estadísticos y funciones de pertenencia. El segundo módulo consiste en el análisis de susceptibilidad de las construcciones representativas a través de funciones de profundidad del impacto físico. Las cuales relacionan los principales componentes de la construcción, incluyendo sus alturas, dimensiones y materiales con los impactos físicos a diferentes niveles de agua. La susceptibilidad del material se calcula con base a estudios internacionales sobre la resistencia de los materiales y un análisis a través de sistemas expertos difusos. Aquí, las funciones de profundidad de impacto físico son considerados como un medio para la interrelación entre el nivel del agua y los impactos físicos. El tercer módulo proporciona las herramientas necesarias para la aplicación de la metodología. Estas herramientas tecnológicas consisten en la arquitectura para la alimentación de los datos relacionados a la tipología de construcciones con las funciones de profundidad del impacto físico apoyado en procesos automáticos. La metodología es probada en tres sitios piloto: (i) en el Barrio Sur en Magangué y (ii) en la barrio de La Peña en Cicuco situado en la llanura inundable del Río Magdalena, Colombia y (iii) en barrio Kleinzschachwitz de la ciudad de Dresden, situado a orillas del río Elba, en Alemania. Las pruebas de la metodología abarca la descripción de la disponibilidad de los datos y la precisión, los pasos a seguir para obtener las funciones profundidad de impacto físico de edificios representativos y la presentación final de la distribución espacial de la susceptibilidad física frente inundaciones El discusión analiza las aportaciones de este trabajo y evalua los resultados de la metodología con relación a los objetivos. Las conclusiones del trabajo, muestran los aportes y limitaciones de la investigación en términos de avances metodológicos y empíricos y la aplicabilidad general de gestión del riesgo de inundaciones.:1 INTRODUCTION 1 1.1 Background 1 1.2 State of the art 2 1.3 Problem statement 6 1.4 Objectives 6 1.5 Approach and outline 6 2 CONCEPTUAL FRAMEWORK 9 2.1 Flood vulnerability 10 2.2 Physical flood vulnerability 12 2.3 Physical flood susceptibility 14 3 METHODOLOGICAL FRAMEWORK 23 3.1 Module 1: Building taxonomy for settlements 24 3.1.1 Extraction of building features 24 3.1.2 Derivation of building parameters for setting up a building taxonomy 38 3.1.3 Selection of representative buildings for a building susceptibility assessment 51 3.2 Module 2: Physical susceptibility of representative buildings 57 3.2.1 Identification of building components 57 3.2.2 Qualification of building material susceptibility 62 3.2.3 Derivation of a depth-physical impact function 71 3.3 Module 3: Technological integration 77 3.3.1 Combination of the depth-physical impact function with the building taxonomic code 77 3.3.2 Tools supporting the physical susceptibility analysis 78 3.3.3 The users and their requirements 79 4 RESULTS OF THE METHODOLOGY TESTING 83 4.1 Pilot site “Kleinzschachwitz” – Dresden, Germany – Elbe River 83 4.1.1 Module 1: Building taxonomy – “Kleinzschachwitz” 85 4.1.2 Module 2: Physical susceptibility of representative buildings – “Kleinzschachwitz” 97 4.1.3 Module 3: Technological integration – “Kleinzschachwitz” 103 4.2 Pilot site “La Peña” – Cicuco, Colombia – Magdalena River 107 4.2.1 Module 1: Building taxonomy – “La Peña” 108 4.2.2 Module 2: Physical susceptibility of representative buildings – “La Peña” 121 4.2.3 Module 3: Technological integration– “La Peña” 129 4.3 Pilot site “Barrio Sur” – Magangué, Colombia – Magdalena River 133 4.3.1 Module 1: Building taxonomy – “Barrio Sur” 133 4.3.2 Module 2: Physical susceptibility of representative buildings – “Barrio Sur” 141 4.3.3 Module 3: Technological integration – “Barrio Sur” 147 4.4 Empirical findings 151 4.4.1 Empirical findings of Module 1 151 4.4.2 Empirical findings of Module 2 155 4.4.3 Empirical findings of Module 3 157 4.4.4 Guidance of the methodology 157 5 DISCUSSION 161 5.1 Discussion on the conceptual framework 161 5.2 Discussion on the methodological framework 161 5.2.1 Discussion on Module 1: the building taxonomic approach 162 5.2.2 Discussion on Module 2: the depth-physical impact function 164 6 CONCLUSIONS AND OUTLOOK 167 6.1 Conclusions 167 6.2 Outlook 168 REFERENCES 171 INDEX OF FIGURES 199 INDEX OF TABLES 201 APPENDICES 20
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