Attenuation due to liquid water is one of the largest uncertainties in radar observations. The effects of attenuation are generally inversely proportional to the wavelength, i.e. observations from X-band radars are more affected by attenuation than those from C- or S-band systems. On the other hand, X-band radars can measure precipitation fields in higher temporal and spatial resolution and are more mobile and easier to install due to smaller antennas. A first algorithm for attenuation correction in single-polarized systems was proposed by Hitschfeld and Bordan (1954) (HB), but it gets unstable in case of small errors (e.g. in the radar calibration) and strong attenuation. Therefore, methods have been developed that restrict attenuation correction to keep the algorithm stable, using e.g. surface echoes (for space-borne radars) and mountain returns (for ground radars) as a final value (FV), or adjustment of the radar constant (C) or the coefficient a. In the absence of mountain returns, measurements from C- or S-band radars can be used to constrain the correction. All these methods are based on the statistical relation between reflectivity and specific attenuation. Another way to correct for attenuation in X-band radar observations is to use additional information from less attenuated radar systems, e.g. the ratio between X-band and C- or S-band radar measurements. Lengfeld et al. (2016) proposed such a method based isotonic regression of the ratio between X- and C-band radar observations along the radar beam. This study presents a comparison of the original HB algorithm and three algorithms based on the statistical relation between reflectivity and specific attenuation as well as two methods implementing additional information of C-band radar measurements. Their performance in two precipitation events (one mainly convective and the other one stratiform) shows that a restriction of the HB is necessary to avoid instabilities. A comparison with vertically pointing micro rain radars (MRR) reveals good performance of two of the methods based in the statistical k-Z-relation: FV and a. The C algorithm seems to be more sensitive to differences in calibration of the two systems and requires additional information from C- or S-band radars. Furthermore, a study of five months of radar observations examines the long-term performance of each algorithm. From this study conclusions can be drawn that using additional information from less attenuated radar systems lead to best results. The two algorithms that use this additional information eliminate the bias caused by attenuation and preserve the agreement with MRR observations.
The interaction of dislocation pile-ups with several tilt grain boundaries (GB) is studied in copper by using a hybrid continuum-atomistic approach. The effects of temperature, pile-up intensity and GB structure on absorption and transmission of slip as a function of local stress state are explored. By considering several high-angle GBs with different misorientation angles, we demonstrate that GB atomic structure primarily defines its ability to accommodate incoming pile-up dislocations, thus limiting the direct transmission of pile-ups through the interface.
Cavaco, E.; Neves, L.; Casas, J. Structure and infrastructure engineering: maintenance, management, life-cycle design and performance Vol. 14, num. 2, p. 1-55 DOI: 10.1080/15732479.2017.1333128 Data de publicació: 2018-02 Article en revista
Management of existing structures has traditionally been based on condition assessment, based on visual inspections, disregarding the susceptibility of different structural types to aging and deterioration. Robustness, as a measure of the effects of unpredictable damage to structural safety can be a complementary information to the results of inspection. Although robustness has mostly been used to evaluate the consequences of extreme events, a similar framework can be used to investigate the result of aging, allowing a better understanding of the potential effects of deterioration and allowing a better allocation of available maintenance funding. In this work, a probabilistic structural robustness indicator is used to quantify the susceptibility of structures to corrosion. The methodology is exemplified through a case study comprising an existing reinforced concrete bridge deck, heavily damaged due to reinforcement corrosion, and finally demolished due to safety concerns. Robustness measures the bridge deck safety tolerance to reinforcement corrosion. The principal effects of corrosion, including loss of area and bond between concrete and steel are modelled using a non-linear finite-element model, coupled with a Response Surface Method to compute the bridge reliability as a function of the corrosion level, and finally used to assess robustness. Results show that the redundancy of the bridge allows significant redistribution of loads between elements with different corrosion levels. As a result, the bridge presents significant robustness and tolerance to reinforcement corrosion.
In this paper we analyse the ejection-collision (EC) orbits of the planar restricted three body problem. Being µ¿¿¿(0, 0.5] the mass parameter, and taking the big (small) primary with mass (µ), an EC orbit will be an orbit that ejects from the big primary, does an excursion and collides with it. As it is well known, for any value of the mass parameter µ¿¿¿(0, 0.5] and sufficiently restricted Hill regions (that is, for big enough values of the Jacobi constant C), there are exactly four EC orbits. We check their existence and extend numerically these four orbits for µ¿¿¿(0, 0.5] and for smaller values of the Jacobi constant. We introduce the concept of n-ejection-collision orbits (n-EC orbits) and we explore them numerically for µ¿¿¿(0, 0.5] and values of the Jacobi constant such that the Hill bounded possible region of motion contains the big primary and does not contain the small one. We study the cases 1¿=¿n¿=¿10 and we analyse the continuation of families of such n-EC orbits, varying the energy, as well as the bifurcations that appear.
For complex geometries, the definition of the subsystems is not a straightforward task. We present here a subsystem identification method based on the direct transfer matrix, which represents the first-order paths. The key ingredient is a cluster analysis of the rows of the powers of the transfer matrix. These powers represent high-order paths in the system and are more affected than low-order paths by damping.
Once subsystems are identified, the proposed approach also provides a quantification of the degree of coupling between subsystems. This information is relevant to decide whether a subsystem may be analysed in a computer model or measured in the laboratory independently of the rest or subsystems or not. The two features (subsystem identification and quantification of the degree of coupling) are illustrated by means of numerical examples: plates coupled by means of springs and rooms connected by means of a cavity.
This volume addresses challenges and solutions in transport and mobility of people and goods with respect to environment, safety, security and socio–economics issues, exploring advanced computational research work and the latest innovations in transport. This book brings together lectures presented at the ECCOMAS Thematic CM3 Conference on Transport held in Jyväskylä, Finland, 25-27 May 2015. It is divided into three parts, I: Reviews and Perspective, II: Computational Methods and Models and III: Translational Research. Each of these parts consists of contributions that present solutions to many transport challenges in this complex, rapidly changing subject. The work contains the latest achievements of European research and technological developments needed for the next decade through computational results of scientific and technical experts who have made essential contributions in transport efficiency in Europe. The material presented here is the state of the art in Transport Modeling, Simulation and Optimization in the fields of Aeronautics, Automotive, Logistics, Maritime and Rails. Furthermore, this volume also answers the question how to apply Computational Research in Transport in order to provide innovative solutions to Green Transportation challenges of identified in the ambitious Horizon 2020 program. This book is intended for students, researchers, engineers and practitioners that are computationally involved in the deployment of Intelligent Transport Systems (ITS) in the areas of optimal use of road, traffic and travel data, traffic and freight management ITS services, road safety and security, sea traffic management, etc.
We present a conceptual and numerical approach to model processes in the Earth's interior that involve multiple phases that simultaneously interact thermally, mechanically and chemically. The approach is truly multiphase in the sense that each dynamic phase is explicitly modelled with an individual set of mass, momentum, energy and chemical mass balance equations coupled via interfacial interaction terms. It is also truly multi-component in the sense that the compositions of the system and its constituent thermodynamic phases are expressed by a full set of fundamental chemical components (e.g. SiO$_2$, Al$_2$O$_3$, MgO, etc) rather than proxies. In contrast to previous approaches these chemical components evolve, react with, and partition into, different phases with different physical properties according to an internally-consistent thermodynamic model. This enables a thermodynamically-consistent coupling of the governing set of balance equations. Interfacial processes such as surface tensions and/or surface energy contributions to the dynamics and energetics of the system are also taken into account. The model presented here describes the evolution of systems governed by Multi-Phase Multi-Component Reactive Transport (MPMCRT) based on Ensemble Averaging and Classical Irreversible Thermodynamics principles. This novel approach provides a flexible platform to study the dynamics and non-linear feedbacks occurring within various natural systems at different scales. This notably includes major-and trace-element transport, diffusion-controlled trace-element re-equilibration or rheological changes associated with melt generation and migration in the Earth's mantle.
Urqueta, H.; Jódar, J.; Herrera Lameli, Ch.; Wilke, H.; Medina, A.; Urrutia, J.; Custodio, E.; Rodríguez, J. Science of the total environment Vol. 612, p. 1234-1248 DOI: 10.1016/j.scitotenv.2017.08.305 Data de publicació: 2018-01 Article en revista
Land surface temperature (LST) seems to be related to the temperature of shallow aquifers and the unsaturated zone thickness (¿ Zuz). That relationship is valid when the study area fulfils certain characteristics: a) there should be no downward moisture fluxes in an unsaturated zone, b) the soil composition in terms of both, the different horizon materials and their corresponding thermal and hydraulic properties, must be as homogeneous and isotropic as possible, c) flat and regular topography, and d) steady state groundwater temperature with a spatially homogeneous temperature distribution. A night time Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image and temperature field measurements are used to test the validity of the relationship between LST and ¿ Zuz at the Pampa del Tamarugal, which is located in the Atacama Desert (Chile) and meets the above required conditions. The results indicate that there is a relation between the land surface temperature and the unsaturated zone thickness in the study area. Moreover, the field measurements of soil temperature indicate that shallow aquifers dampen both the daily and the seasonal amplitude of the temperature oscillation generated by the local climate conditions. Despite empirically observing the relationship between the LST and ¿ Zuz in the study zone, such a relationship cannot be applied to directly estimate ¿ Zuz using temperatures from nighttime thermal satellite images. To this end, it is necessary to consider the soil thermal properties, the soil surface roughness and the unseen water and moisture fluxes (e.g., capillarity and evaporation) that typically occur in the subsurface.
Boano, F.; Rizzo, A.; Samsó, R.; Garcia, J.; Revelli, R.; Ridolfi, L. Science of the total environment Vol. 612, p. 1480-1487 DOI: 10.1016/j.scitotenv.2017.08.265 Data de publicació: 2018-01 Article en revista
The average organic and hydraulic loads that Constructed Wetlands (CWs) receive are key parameters for their adequate long-term functioning. However, over their lifespan they will inevitably be subject to either episodic or sustained overloadings. Despite that the consequences of sustained overloading are well known (e.g., clogging), the threshold of overloads that these systems can tolerate is difficult to determine. Moreover, the mechanisms that might sustain the buffering capacity (i.e., the reduction of peaks in nutrient load) during overloads are not well understood. The aim of this work is to evaluate the effect of sudden but sustained organic and hydraulic overloads on the general functioning of CWs. To that end, the mathematical model BIO_PORE was used to simulate five different scenarios, based on the features and operation conditions of a pilot CW system: a control simulation representing the average loads; 2 simulations representing +10% and +30% sustained organic overloads; one simulation representing a sustained +30% hydraulic overload; and one simulation with sustained organic and hydraulic overloads of +15% each. Different model outputs (e.g., total bacterial biomass and its spatial distribution, effluent concentrations) were compared among different simulations to evaluate the effects of such operation changes. Results reveal that overloads determine a temporary decrease in removal efficiency before microbial biomass adapts to the new conditions and COD removal efficiency is recovered. Increasing organic overloads cause stronger temporary decreases in COD removal efficiency compared to increasing hydraulic loads. The pace at which clogging develops increases by 10% for each 10% increase on the organic load.
The role of edge dislocations as sinks for small radiation induced defects in bcc-Fe is investigated by means of atomistic computer simulation. In this work we investigate by Molecular Statics (T = 0K) the interaction between an immobile dislocation line and defect clusters of small sizes invisible experimentally. The study highlights in particular the anisotropy of the interaction and distinguishes between absorbed and trapped defects. When the considered defect intersects the dislocation glide plane and the distance from the dislocation line to the defect is on the range between 2 nm and 4 nm, either total or partial absorption of the cluster takes place leading to the formation of jogs. Residual defects produced during partial absorption pin the dislocation. By the calculation of stress-strain curves we have assessed the strength of those residues as obstacles for the motion of the dislocation, which is reflected on the unpinning stresses and the binding energies obtained. When the defect is outside this range, but on planes close to the dislocation glide plane, instead of absorption we have observed a capture process. Finally, with a view to introducing explicitly in kinetic Monte Carlo models a sink with the shape of a dislocation line, we have summarized our findings on a table presenting the most relevant parameters, which define the interaction of the dislocation with the defects considered.
The most singular characteristic of pervious concrete is its interconnected porosity that allows water to flow through at high rates. The objective of this paper is to develop and validate an advanced DEM-CFD model to assess the permeability of pervious concrete numerically, taking into account the influence of the composition and of the compaction process. An extensive experimental program with 1 aggregate grading size, 4 paste contents and 3 degrees of compaction was conducted to validate the numerical approach. Results show that the DEM-CFD model is capable of predicting the permeability depending on the variables considered here. Moreover, flow parameters derived from the numerical simulations help understand the experimental results. The study confirms that, instead of relying on trial and error experiments, it is possible to use advanced numerical models to accelerate the definition of mixes and the production process, reducing the time, efforts and costs required.
The search for environmentally neutral alternative fuels had revived the interest for microalgae-bacteria wastewater treatment systems. The potential achieving of bioproducts from microalgae biomass has also greatly contributed. The reactions that occur in these systems are complex, and the degree of scientific knowledge is still scarce compared to that of conventional bacteria wastewater treatments. Mathematical models offer a great opportunity to study the simultaneous effect of the multiple factors affecting microalgae and bacteria, thus allowing for the prediction of final biomass production, and contributing to the system design optimization in terms of operation and control. During the last decades, numerous models describing microalgae growth have been proposed. However, a lower number of integral models considering microalgae as well as bacteria is available. In this paper, the evolution of microalgae models from simple steady-state models (usually dependent on one factor) to more complex dynamic models (with two or more factors) has been revised. A summary of integrated microalgae-bacteria models has been reviewed, outlining their main features and presenting their processes and value parameters. Eventually, a critical discussion on integrated models has been put forward.
An integral mechanistic model describing the complex interactions in mixed algal-bacterial systems was developed. The model includes crucial physical, chemical and biokinetic processes of microalgae as well as bacteria in wastewater. Carbon-limited microalgae and autotrophic bacteria growth, light attenuation, photorespiration, temperature and pH dependency are some of the new features included. The model named BIO_ALGAE was built using the general formulation and structure of activated sludge models (ASM), and it was implemented in COMSOL Multiphysics™ platform. Calibration and validation were conducted with experimental data from two identical pilot HRAPs receiving real wastewater. The model was able to simulate the dynamics of different components in the ponds, and to predict the relative proportion of microalgae (58–68% in average of total suspended solids (TSS) and bacteria (30–20% in average of TSS). Microalgae growth resulted strongly influenced by the light factor fL(I), decreasing microalgae concentrations from 40 to 60%. Furthermore, reducing the influent organic matter concentration of 50% and 70%, model predictions indicated that microalgae production increased from (8.7 g TSS m- 2d- 1 to 13.5 g TSS m- 2d- 1) due to the new distribution of particulate components. The proposed model could be an efficient tool for industry to predict the production of microalgae, as well as to design and optimize HRAPs.
Nadal, A.; Alamús, R.; Pipia, L.; Ruiz , A.; Corbera, J.; Cuerva, E.; Rieradevall, J.; Josa, A. Science of the total environment Vol. 601-602, p. 1-15 DOI: 10.1016/j.scitotenv.2017.03.214 Data de publicació: 2017-12-01 Article en revista
The integration of rooftop greenhouses (RTGs) in urban buildings is a practice that is becoming increasingly important in the world for their contribution to food security and sustainable development. However, the supply of tools and procedures to facilitate their implementation at the city scale is limited and laborious. This work aims to develop a specific and automated methodology for identifying the feasibility of implementation of rooftop greenhouses in non-residential urban areas, using airborne sensors. The use of Light Detection and Ranging (LIDAR) and Long Wave Infrared (LWIR) data and the Leica ALS50-II and TASI-600 sensors allow for the identification of some building roof parameters (area, slope, materials, and solar radiation) to determine the potential for constructing a RTG. This development represents an improvement in time and accuracy with respect to previous methodology, where all the relevant information must be acquired manually.
The methodology has been applied and validated in a case study corresponding to a non-residential urban area in the industrial municipality of Rubí, Barcelona (Spain). Based on this practical application, an area of 36,312 m2 out of a total area of 1,243,540 m2 of roofs with ideal characteristics for the construction of RTGs was identified. This area can produce approximately 600 tons of tomatoes per year, which represents the average yearly consumption for about 50% of Rubí total population.
The use of this methodology also facilitates the decision making process in urban agriculture, allowing a quick identification of optimal surfaces for the future implementation of urban agriculture in housing. It also opens new avenues for the use of airborne technology in environmental topics in cities.
The Discrete Element Method (DEM) has been used for modelling continua, like concrete or rocks. However, it requires a big calibration effort, even to capture just the linear elastic behavior of a continuum modelled via the classical force-displacement relationships at the contact interfaces between particles. In this work we propose a new way for computing the contact forces between discrete particles. The newly proposed forces take into account the surroundings of the contact, not just the contact itself. This brings in the missing terms that provide an accurate approximation to an elastic continuum, and avoids calibration of the DEM parameters for the purely linear elastic range.
Corada, M.; Candela, L.; Torres-Fuentes, N.; Pintado-Herrera, M.; Paniw, M.; González-Mazo, E. Science of the total environment Vol. 605-606, p. 770-783 DOI: 10.1016/j.scitotenv.2017.06.049 Data de publicació: 2017-12 Article en revista
This study is focused on the Guadalete River basin (SW, Spain), where extreme weather conditions have become common, with and alternation between periods of drought and extreme rainfall events. Combined sewer overflows (CSOs) occur when heavy rainfall events exceed the capacity of the wastewater treatment plants (WWTP), as well as pollution episodes in parts of the basin due to uncontrolled sewage spills and the use of reclaimed water and sludge from the local WWTP. The sampling was carried out along two seasons and three campaigns during dry (March 2007) and extreme rainfall (April and December 2010) in the Guadalete River, alluvial aquifer and Jerez de la Frontera aquifer. Results showed minimum concentrations for synthetic surfactants in groundwater (< 37.4 µg·L- 1) during the first campaign (dry weather conditions), whereas groundwater contaminants increased in December 2010 as the heavy rainfall caused the river to overflow. In surface water, surfactant concentrations showed similar trends to groundwater observations. In addition to surfactants, pharmaceuticals and personal care products (PPCPs) were analyzed in the third campaign, 22 of which were detected in surface waters. Two fragrances (OTNE and galaxolide) and one analgesic/anti-inflammatory (ibuprofen) were the most abundant PPCPs (up to 6540, 2748 and 1747 ng·L- 1, respectively). Regarding groundwater, most PPCPs were detected in Jerez de la Frontera aquifer, where a synthetic fragrance (OTNE) was predominant (up to 1285 ng·L- 1).
Mendez, C.; Podestá, J.; Lloberas-Valls, O.; Toro, S.; Huespe, A.; Oliver, J. International journal for numerical methods in engineering Vol. 112, num. 10, p. 1353-1380 DOI: 10.1002/nme.5560 Data de publicació: 2017-12 Article en revista
A topology optimization technique based on the topological derivative and the level set function is utilized to design/synthesize the micro-structure of a pentamode material for an acoustic cloaking device. The technique provides a micro-structure consisting of a honeycomb lattice composed of needle-like and joint members. The resulting metamaterial shows a highly anisotropic elastic response with effective properties displaying a ratio between bulk and shear moduli of almost 3 orders of magnitude. Furthermore, in accordance with previous works in the literature, it can be asserted that this kind of micro-structure can be realistically fabricated. The adoption of a topology optimization technique as a tool for the inverse design of metamaterials with applications to acoustic cloaking problems is one contribution of this paper. However, the most important achievement refers to the analysis and discussion revealing the key role of the external shape of the prescribed domain where the optimization problem is posed. The efficiency of the designed micro-structure is measured by comparing the scattering wave fields generated by acoustic plane waves impinging on bare and cloaked bodies.
The assessment of historical structures requires appropriate knowledge of the behaviour of the investigated materials. Concerning masonry, its mechanical characterisation is a challenging task, since its composite nature requires the careful evaluation of the behaviour of its material components. In particular, the experimental assessment of the strength of existing mortar in historical structures still encounters several difficulties. This study investigates a novel Minor Destructive Testing (MDT) technique virtually equivalent to the vane test used for soils. The instrumentation, called herein Torque Penetrometric Test (TPT), is composed of a steel nail with four protruding teeth and a torque wrench. The test consists in inserting the toothed nail into a mortar joint and then applying a torque by means of a dynamometric key, until reaching the failure of the material. This work presents a novel interpretation theory based on basic concepts of fracture mechanics and applied to the micro-mechanical analysis of the stress state induced by the instrument on the investigated mortar. The proposed interpretative theory is validated through the execution of experimental tests in the laboratory and in a historical masonry building. The test proves to be effective for a quick in-situ MDT evaluation of the strength of existing mortars.
Chiumenti, M.; Neiva, E.; Salsi, E.; Cervera, M.; Badia, S.; Moya, J.; Chen, Z.; Lee, C.; Davies, C. Additive Manufacturing Vol. 18, p. 171-185 DOI: 10.1016/j.addma.2017.09.002 Data de publicació: 2017-12 Article en revista
In this work a finite-element framework for the numerical simulation of the heat transfer analysis of additive manufacturing processes by powder-bed technologies, such as Selective Laser Melting, is presented. These kind of technologies allow for a layer-by-layer metal deposition process to cost-effectively create, directly from a CAD model, complex functional parts such as turbine blades, fuel injectors, heat exchangers, medical implants, among others. The numerical model proposed accounts for different heat dissipation mechanisms through the surrounding environment and is supplemented by a finite-element activation strategy, based on the born-dead elements technique, to follow the growth of the geometry driven by the metal deposition process, in such a way that the same scanning pattern sent to the numerical control system of the AM machine is used. An experimental campaign has been carried out at the Monash Centre for Additive Manufacturing using an EOSINT-M280 machine where it was possible to fabricate different benchmark geometries, as well as to record the temperature measurements at different thermocouple locations. The experiment consisted in the simultaneous printing of two walls with a total deposition volume of 107 cm3 in 992 layers and about 33,500 s build time. A large number of numerical simulations have been carried out to calibrate the thermal FE framework in terms of the thermophysical properties of both solid and powder materials and suitable boundary conditions. Furthermore, the large size of the experiment motivated the investigation of two different model reduction strategies: exclusion of the powder-bed from the computational domain and simplified scanning strategies. All these methods are analysed in terms of accuracy, computational effort and suitable applications.
Botella, R.; Perez, F.; Riahi, E.; López-Montero, T.; Miro, R.; Martinez, A. Construction & building materials Vol. 156, p. 809-818 DOI: 10.1016/j.conbuildmat.2017.09.036 Data de publicació: 2017-12 Article en revista
This paper's objective is to evaluate the reversible phenomena that take place when asphalt materials are subjected to cyclic loads, i.e., self-heating and thixotropy. A strain sweep test was adapted to capture the stiffness variation of binders with the change in strain amplitude. The evolution of the internal temperature of the binder during the test was measured. Results show that the temperature can increase very significantly during cyclic testing and can account for a great part of all stiffness reduction captured during the test at different strain amplitudes. These results led to the conclusion that internal heating should be very important in asphalt mixtures as well. For that reason two types of time sweep tests were performed on the same mixture, with the introduction of rest periods in one of them long enough to let the inside temperature of the material lower after cycling. The results showed that the specimen that was allowed to cool down did not experience any loss of stiffness, while the specimen submitted to the conventional time sweep test failed in a few cycles. These results show the importance of the sequencing of loading and discourage the application of the Miner's law to estimate pavement life.
Ortiz, J. A.; de la Fuente, A.; Mena Sebastia, F.; Segura, I.; Aguado, A. Construction & building materials Vol. 156, p. 230-241 DOI: 10.1016/j.conbuildmat.2017.08.188 Data de publicació: 2017-12 Article en revista
This research focuses on designing and characterizing steel-fibre-reinforced self-compacting concrete using recycled aggregates (SFR-SCC-RA). Six different concrete dosages have been designed, and two extensive mechanical and physical characterization programs have been conducted. The first program was developed in a concrete production plant to verify the compatibility of the new material with the existing production systems. The second program was developed in a laboratory under controlled temperature and humidity conditions. Although compressive strengths greater than 25 N/mm2 have been reached (which allows the material to be classified as structural), the design in this initial phase is oriented to applications with limited mechanical requirements (e.g., foundations, earth retaining walls and pavements, in which design forces are moderate).
Los métodos numéricos son decisivos en la ingeniería para la conservación de estructuras de mampostería existentes y el diseño de estructuras nuevas. Entre ellos, los métodos ma-cro-mecánicos de elementos finitos, basados en el concepto de fisuras distribuidas, son habitualmente los preferidos como opción asequible para el análisis de grandes estructuras de mampostería. Sin embargo, suelen resultar en a una representación poco realista del daño, distribuido en grandes áreas de la estructura, lo que impide la correcta interpretación del patrón de daño. Además, esta metodología presenta una patología más crítica, la de-pendencia de la malla, que influye notablemente en las predicciones de seguridad y estabi-lidad.Para superar estas limitaciones, esta tesis propone una nueva herramienta numérica basada en el enriquecimiento del clásico enfoque de fisuras distribuidas con un algoritmo de tra-zado local. El objetivo de este modelo de daño localizado es el análisis no-lineal de las estructuras de mampostería de manera realista y eficiente con una representación mejora-da de fisuras.El comportamiento no lineal de la mampostería se simula a través de la adopción de un modelo de mecánica de daño continuo con dos índices de daño, permitiendo la diferen-ciación entre las respuestas mecánicas de tensión y compresión de la mampostería. En este contexto, se propone e implementa una nueva formulación explícita para la evolución de deformaciones irreversibles. Se derivan dos nuevas expresiones para la regularización del ablandamiento de tracción y compresión según el ancho de banda de la fisura, garantizan-do la objetividad del modelo de daño al respecto del tamaño de la malla.La simulación del comportamiento estructural de las estructuras de mampostería en condi-ciones de carga y contorno generales precisa de algunos desarrollos en el contexto de los algoritmos locales de trazado. Con este objetivo, se presenta la mejora de los algoritmos locales de trazado con nuevos procedimientos que posibilitan la simulación de fisuración múltiple, arbitraria e secante bajo cargas monótonas y cíclicas. Además, se investiga el efecto de diferentes criterios de propagación de fisuras y se aborda la selección entre más de un plano de falla posible.El modelo de daño localizado propuesto se valida mediante la simulación de una serie de ejemplos estructurales. Éstos van desde pruebas a pequeña escala en probetas de hormi-gón, con pocas fisuras dominantes, hasta estructuras de mampostería de mediana y gran escala con fisuración múltiple de tracción, de cortante y de flexión. Los análisis se compa-ran con los resultados analíticos, experimentales y numéricos obtenidos con métodos al-ternativos disponibles en la literatura. El modelo de daño localizado mejora en gran medi-da la independencia de la malla del clásico método de fisuras distribuidas y reproduce patrones de daño y mecanismos de colapso de una manera eficiente y realista.Palabras clave: Mampostería, Materiales cuasi-frágiles, Método de elementos finitos, Lo-calización de deformaciones, Algoritmo de trazado, Mecánica de daño continuo, Defor-maciones irreversibles, Fisuración de tracción/cortante/flexión, Fisuras secantes, Depen-dencia de la malla, carga cíclica de cortante
Separable approximations efficiently deal with high-dimensional data. In particular the Proper Generalized Decomposition (PGD) provides separable functions as solutions of boundary value problems. The general PGD framework contains a large family of methodologies, all of them providing solutions in for of separable objects, that is a sum of terms, being each term a product of J D functions (or arrays). Some of the PGD methodologies have been conceived to tackle nonlinear problems. We present a general methodology to perform basic operations (sum, product, division. exponentiation .... ) for this type of objects. The idea is based on the principie of the PGD compression, that is a separable least squares approximation of any multidimensional function. The PGD compression is extensively used in practice to compact the separable solution in less terms without loss of accuracy. Here, this concept is applied to both algebraic tensor structures and functions in multidimensional Cartesian domains. Moreover, a straightforward extension of this concept is devised to operate with multidimensional objects stored in the separable format. That allows creating a toolbox of PGD arithmetic operators. Thus, the toolbox is used to perform elemental operations with PGD type objects. This is of particular interest to solve nonlinear problems with PGD techniques by simply replicating the iterative algebraic solvers that are used in the standard Finite Element framework.
Design optimization, among other applications of industrial interest, requi re fast and multi ple queries of some parametric model. The Proper Generalized Decomposition (PGD) provides a separable so\ution, a computational vademecum, explicitly dependent on the parameters. This explicit parametric solution is efficiently computed with a greedy algorithm combined with an alternated directions scheme and can be stored in a compact form. This strategy has been successfully employed in many problems in com putational mechanics. The application to problems with saddle paint structure raises some difficulties requiring further attention in particular when the parameters descrihe the geometry of the computational domain. This presentation proposes a novel PGD formulation for the parameterized Stokes problem. Various possibilities of the separated forms of the PGD solutions are discussed and analyzed, selecting the more viable opti on. The efficacy of the proposed methodology is demonstrated in numerical exam ples for both Stokes and Brinkman models. Moreover, geometrically parameterized problems are further studied and discussed. These ftow problems require in many occasions to use high order methods in order to efticiently capture all the complexity of the ftow. Thus, the specificities or Lhe geometrically parameterized PGD strategy a discussed and high fidelity techniques are proposed to improve accurncy and performance in the offline phase.
A modelling procedure to address the tunnel–anhydritic rock interaction is described in this paper. The model incorporates the basic physico-chemical phenomena involved in rock swelling, often observed during excavation and subsequent operation of tunnels. It includes (a) a provision for rock damage during tunnel excavation, (b) the precipitation of gypsum crystals in discontinuities and (c) a stress-dependent relationship between swelling strains and mass of gypsum precipitation. The model includes hydro-mechanical coupling and the transport of sulfate salts dissolved in the massif water. Rock damage is described by the development of a network of fractures that increases permeability and allows gypsum crystal growth. Field information, laboratory data and monitoring records available for Lilla tunnel, located in the province of Tarragona, Spain and excavated in Tertiary anhydritic claystone, were selected as a convenient benchmark case to test model capabilities. Predictions and measurements (swelling records of the unlined tunnel floor and swelling pressures against a structural invert) were found to agree reasonably well.
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In this paper we propose a Finite Element model for analyzing closed membranes (“bags”) interacting with internal and external (surrounding) fluids. The approach is based on embedding a Lagrangian monolithic model describing the membrane containing an internal fluid into an Eulerian external fluid model. The combination of kinematic frameworks allows us to accurately track the location of the membrane and naturally represent flow variables discontinuities across it. In order to obtain stable coupling for membrane materials with low density, a slight fluid compressibility is assumed. The coupling between the membrane and the internal fluid is automatically accounted for by a monolithic set-up. The filled membrane and the external fluid are coupled in a Dirichlet–Neumann fashion. The model is validated in several numerical examples and its potential application to a civil engineering problem of coast protection via water-filled bag reefs is shown.
This paper discusses the finite element modeling of cracking in quasi-brittle materials. The problem is addressed via a mixed strain/displacement finite element formulation and an isotropic damage constitutive model. The proposed mixed formulation is fully general and is applied in 2D and 3D. Also, it is independent of the specific finite element discretization considered; it can be equally used with triangles/tetrahedra, quadrilaterals/hexahedra and prisms. The feasibility and accuracy of the method is assessed through extensive comparison with experimental evidence. The correlation with the experimental tests shows the capacity of the mixed formulation to reproduce the experimental crack path and the force–displacement curves with remarkable accuracy. Both 2D and 3D examples produce results consistent with the documented data. Aspects related to the discrete solution, such as convergence regarding mesh resolution and mesh bias, as well as other related to the physical model, like structural size effect and the influence of Poisson’s ratio, are also investigated. The enhanced accuracy of the computed strain field leads to accurate results in terms of crack paths, failure mechanisms and force displacement curves. Spurious mesh dependency suffered by both continuous and discontinuous irreducible formulations is avoided by the mixed FE, without the need of auxiliary tracking techniques or other computational schemes that alter the continuum mechanical problem.
The final publication is available at Springer via http://dx.doi.org/10.1007/s00466-017-1438-8
In this paper, the flexural response of extruded wrought aluminium girders is presented. This structural element is intended for usage in marine structures such as light docks, marinas and yacht ports. Ease of use, durability, reduced weight, manoeuvrability and the potential development of bespoke sections are appealing properties in such structures that are fulfilled satisfactorily by this type of aluminium elements. Both experimental and numerical analyses are presented. Experimentally, modules of the girders are tested with loading about both minor and major axes. Numerically, the tests are satisfactorily reproduced for the sake of validation and a subsequent exploitation of the model is addressed for further study of the structural response of the girders. A discussion of the results is presented with some design recommendations of these particular structural elements.
Dialami , N.; Chiumenti, M.; Cervera, M.; Segatori, A.; Osikowicz, W. International journal of mechanical sciences Vol. 133, p. 555-567 DOI: 10.1016/j.ijmecsci.2017.09.022 Data de publicació: 2017-11 Article en revista
Friction is one of the main heat generation mechanisms in Friction Stir Welding (FSW). This phenomenon occurs between the pin and the workpiece as the rotating tool moves along the weld line. An accurate friction model is essential for obtaining realistic results in a FSW simulation in particular temperature, forces and torque. In this work, a modified Norton's friction law is developed. The suggested enhanced friction model aims at providing not only the realistic temperature field but also the forces and torque. This model does not exclusively relate the frictional shear stress to the sliding velocity; conversely it takes into account the effect of non-uniform pressure distribution under the shoulder, as this latter has an important role in the process of heat generation. Longitudinal, transversal and vertical forces and torque are numerically calculated. The effect of the enhanced friction model is reflected in these forces. In particular, it leads to a more realistic estimation of the transversal and longitudinal forces in comparison with the results obtained using former models. The friction model is successfully validated by the experimental measurements provided by the industrial partner (Sapa). The experimental analysis is performed for the material characterization, the calibration of the friction model and, more generally, the assessment of the overall numerical strategy proposed for the FSW simulation.
Design optimization and uncertainty quantification, among other applications of industrial interest, require fast or multiple queries of some parametric model. The Proper Generalized Decomposition (PGD) provides a separable solution, a computational vademecum explicitly dependent on the parameters, efficiently computed with a greedy algorithm combined with an alternated directions scheme and compactly stored. This strategy has been successfully employed in many problems in computational mechanics. The application to problems with saddle point structure raises some difficulties requiring further attention. This article proposes a PGD formulation of the Stokes problem. Various possibilities of the separated forms of the PGD solutions are discussed and analyzed, selecting the more viable option. The efficacy of the proposed methodology is demonstrated in numerical examples for both Stokes and Brinkman models.
In this paper, a set of digital artifacts related to simple examples of structural engineering are presented. The artifacts are real-time applications and visualizations of typical problems students from the architecture, engineering, and construction (AEC) schools are acquainted with. The real-time nature of the examples allow a high level of interaction between humans and the classic visualization of results, namely, bending and shear force diagrams, internal stresses distributions, and contour plots. These artifacts may provide in AEC a twofold educational target: (i) for users, to provide visual understanding in real time of typical problems that must be understood in classic lectures of structural engineering; (ii) for developers, to provide meaningful applications of applied digital fabrication using sensors, microcontrollers, and GUI's and their potential in the development of tools related to Structural Health Monitoring (SHM) and the Internet of Things (IoT) among students of the AEC sector.
This is the peer reviewed version of the following article: [ Chacón R, Codony D, Toledo Á. From physical to digital in structural engineering classrooms using digital fabrication. Comput appl eng educ. 2017;25:927–937. https://doi.org/10.1002/cae.21845 ], which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/cae.21845/full. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
Riahi, E.; Allou, F.; Botella, R.; Dubois, F.; Absi, J.; Petit, C. International journal of fatigue Vol. 104, p. 334-341 DOI: 10.1016/j.ijfatigue.2017.07.016 Data de publicació: 2017-11 Article en revista
This paper studies the reduction in complex modulus when a bituminous binder is subjected to the fatigue test, along with the ability of this material to recover such a loss in modulus. It has been demonstrated in the literature that during a fatigue test, a rapid and reversible decrease of complex modulus can be observed at the beginning of the test. This reversible decrease is not correlated with fatigue and has been explained by the existence of reversible phenomena, such as thixotropy, self-heating, nonlinearity, etc. The aim of this work is to quantify the self-heating and determine its share in the reversible reduction of complex modulus under cyclic loading. A strain sweep test has been developed with different loading steps, followed by rest periods after each loading phase. The loading level increases with each step, and the loading phases allow observing the modulus decrease, while the rest periods are introduced to observe modulus recovery after each loading level. A complete recovery of modulus means that the modulus diminution is due to a reversible phenomenon however a partial recovery of modulus notifies the presence of nonreversible phenomenon (such as damage). In using this approach, the influence of loading level on both complex modulus decrease and recovery can be examined. In order to quantify self-heating during testing, the sample temperature is measured by embedding a thermocouple probe inside the sample during its manufacturing. To obtain the relationship between complex modulus and temperature, the complex modulus test results have been interpreted herein. A thermoviscoelastic numerical simulation was conducted to determine the temperature field in the material and quantify the variation in complex modulus with respect to self-heating. Results show a temperature variation of 11 °C inside the sample. A comparison between experimental and numerical results indicates that the numerical model perfectly predicts the variations in both temperature and complex modulus until a certain strain level, where the damage, thixotropy or other factors have not appeared yet. It is also observed that the reversible complex modulus decrease can be explained by self-heating.
Houzeaux, G.; Cajas, J.; Discacciati, M.; Eguzkitza, B.; Gargallo, A.; Rivero, M.; Vázquez, M. Archives of computational methods in engineering Vol. 24, num. 4, p. 1033-1070 DOI: 10.1007/s11831-016-9198-8 Data de publicació: 2017-11 Article en revista
Domain composition methods (DCM) consist in obtaining a solution to a problem, from the formulations of the same problem expressed on various subdomains. These methods have therefore the opposite objective of domain decomposition methods (DDM). Indeed, in contrast to DCM, these last techniques are usually applied to matching meshes as their purpose consists mainly in distributing the work in parallel environments. However, they are sometimes based on the same methodology as after decomposing, DDM have to recompose. As a consequence, in the literature, the term DDM has many times substituted DCM. DCM are powerful techniques that can be used for different purposes: to simplify the meshing of a complex geometry by decomposing it into different meshable pieces; to perform local refinement to adapt to local mesh requirements; to treat subdomains in relative motion (Chimera, sliding mesh); to solve multiphysics or multiscale problems, etc. The term DCM is generic and does not give any clue about how the fragmented solutions on the different subdomains are composed into a global one. In the literature, many methodologies have been proposed: they are mesh-based, equation-based, or algebraic-based. In mesh-based formulations, the coupling is achieved at the mesh level, before the governing equations are assembled into an algebraic system (mesh conforming, Shear-Slip Mesh Update, HERMESH). The equation-based counterpart recomposes the solution from the strong or weak formulation itself, and are implemented during the assembly of the algebraic system on the subdomain meshes. The different coupling techniques can be formulated for the strong formulation at the continuous level, for the weak formulation either at the continuous or at the discrete level (iteration-by-subdomains, mortar element, mesh free interpolation). Although the different methods usually lead to the same solutions at the continuous level, which usually coincide with the solution of the problem on the original domain, they have very different behaviors at the discrete level and can be implemented in many different ways. Eventually, algebraic-based formulations treat the composition of the solutions directly on the matrix and right-hand side of the individual subdomain algebraic systems. The present work introduces mesh-based, equation-based and algebraic-based DCM. It however focusses on algebraic-based domain composition methods, which have many advantages with respect to the others: they are relatively problem independent; their implicit implementation can be hidden in the iterative solver operations, which enables one to avoid intensive code rewriting; they can be implemented in a multi-code environment.
de Sousa, R.; Pereira, L.C.C.; Trindade, W.N.; da Costa, R.M.; Jimenez, J.A. Ocean and coastal management Vol. 149, p. 96-106 DOI: 10.1016/j.ocecoaman.2017.09.011 Data de publicació: 2017-11 Article en revista
The present study proposes a diagnosis of the conditions and impacts on estuarine beaches of the Amazonian coast based on the application of the DPSIR (Driving Forces, Pressures, State, Impact, Responses) model, which identifies the natural and anthropogenic drivers affecting the environment. Natural drivers are related primarily to the accentuated hydrodynamic processes, high rainfall and fluvial discharge. The anthropogenic driver is related to the lack of planning for beach development. These human pressures result in a reduction in the quality of the beaches through microbiological contamination, the accumulation of garbage on the sand and in the water, sewage outfalls, and overcrowding which, combined with the intense local hydrodynamics and the lack of planning of recreational activities (zoning, warning signs, lifeguard coverage) may increase the risk of accidents for beachgoers, such as drowning, and injuries caused by motorboats, jet skis and stingrays. Despite all the problems identified, no response whatsoever was observed from the local authorities. The results of the DPSIR analysis indicate an urgent need for the implementation of beach management plans to improve the conditions of the beaches and in particular their safety, as well as identifying the obligations of the local authorities responsible for the future development of the Amazon coast.
This paper presents a comprehensive study on the application of global plastic design methods, not currently allowed in European specification provisions, to stainless steel rectangular and square hollow section continuous beams. The analysis of experimental and numerical continuous beam strengths highlighted that ultimate capacity predictions calculated based on global elastic analysis result in a considerable conservatism due to strain hardening and bending moment redistribution effects. Alternatively, the assessment and reliability analyses of the traditional plastic design methods demonstrated that the Class 1 cross-section limit provided in the European specification can be safely applied for the partial safety factor ¿M0 currently provided. However, the analysis evidenced that including bending moment redistribution in capacity predictions is not enough since strain hardening effects play an important role when stocky cross-sections are analysed. Thus, the Continuous Strength Method for indeterminate structures was also assessed and it was found to provide accurate capacity predictions for all analysed stainless steel grades. Finally, an alternative Direct Strength Method design approach is proposed for stainless steel continuous beams based on the Direct Strength Method bending capacity. The proposed method, statistically validated, accounts for strain hardening effects and moment redistribution and provides the best resistance predictions among the different design methods considered
This paper presents a quantitative environmental impact assessment tool for the decision making of construction processes including structures, infrastructures and buildings by means of an Environmental Impact Index (EII) to be applied at design and/or construction stages. The research is based on multi-attribute utility theory, interviews with experts representatives of the different stakeholders in construction, and an analysis of fifty-nine European and Spanish environmental legislative acts. The resulting tool was applied to two construction alternatives for road drains (one precast and one cast-in-place). The findings show that the tool enables the prioritisation of construction processes and the selection of the best alternative in terms of environmental impact and that the results are stable to reasonable weight variations. The tool contributes to decision making in the context of project management in construction: it can help professionals in public administration, and design and construction companies. It helps to quantify the cradle-to-gate impact of construction work, which has usually been less studied than the operational impact in the life-cycle assessment of buildings. The tool is being piloted in construction projects of the Barcelona City Council.
This article presents a mechanical formulation to estimate the strength of transversally stiffened steel plate girders subjected to patch loading, in this particular case, with closely space stiffeners. Steel plate girders with closely spaced stiffeners are occasionally found in bridge design and for such cases, the current EN1993-1-5 rules underestimate the strength of the webs to transverse forces. A FE-based parametric investigation is conducted to estimate the web strength to patch loading. The results are compared to the results obtained from classical beam theory in combination with the proposed formulation. A notional plate girder is analyzed to demonstrate the potential of the formulation for daily routine designs. Results indicate that the proposed formulation does a better job in predicting the web strength of transversely stiffened girders subjected to patch loading than the EN1993-1-5 specification, and thus yield a lighter and more economical design for these specific girder geometries.
Although cracking resistance is one of the most important properties affecting the durability of asphalt mixtures, this property is often not considered as a requirement in the mixture design stage, and the bitumen content is determined from other properties (voids content, permanent deformation, or water sensitivity, etc...). The effect of bitumen content on the cracking resistance of an asphalt concrete mixture (type AC) was analyzed in this paper by means of different types of tests. Firstly, a cyclic strain sweep test (EBADE test) was used to obtain the evolution of the complex modulus and dissipated energy density with the number of cycles as well as the failure strain. Results from a previous research study helped approximate the fatigue laws of the mixtures studied, providing insight into the effect of binder content on the fatigue life of the mixtures manufactured with 3, 4, 5, and 6 % of binder by mixture mass. Secondly, a direct tensile monotonic test (Fénix test) was used to determine the strength and fracture energy of the mixture. The mixture with the 5 % binder content exhibited better results in all tests, indicating that this value would be the optimum binder content as it showed good consistency between the cyclic and monotonic tests employed.
En el presente estudio se describen las características litoestratigráficas de las formaciones yesíferas de Canelles (Keuper inferior) y de Lécera (Jurásico Inferior) aflorantes en la zona de Camarasa, en el frente Surpirenaico Catalán. La serie de la Fm. Lécera constituye una alternancia cíclica de capas de yesos y carbonatos de cerca de 300 m de espesor. El yeso es de litofacies laminada gris, laminada blanca y masiva blanca. Los carbonatos son brechas dolomíticas y dolomicritas finamente estratificadas. Por el contrario, la Fm. Canelles forma una serie yesífera masiva de 100 m de espesor, con capas menores de carbonato restringidas a la base de la formación y a su parte media. En la base el carbonato es de litofacies dolomicrita laminada, mientras que en la parte media es de litofacies margodolomía laminada, dolomicrita laminada y oolítica, formando cuatro ciclos de pocos metros de espesor. Ambas formaciones se originaron en sistemas evaporíticos de tipo lagoon sulfatado, muy estables, alimentados por aguas marinas y alejados de la influencia de aportes detríticos. En estos lagoons la sedimentación fue principalmente yesífera, en facies laminada, y con niveles subordinados de carbonatados, representando respectivamente estadios de mayor y menor concentración relativa del agua, y sin registro de sales más solubles (halita).
The behaviour of austenitic, ferritic and duplex stainless steel Rectangular and Square Hollow Section members subjected to compression and combined loading is investigated in this paper. A full slenderness range Direct Strength Method (DSM) approach is proposed based on experimental results and numerical strengths obtained from FE parametric studies. The method accounts for local buckling effects and enhanced material properties are also incorporated for those members stable enough to allow partial yielding of the cross-sections. The proposed method is based on strength curves previously provided for cross-sections although additional limitations have been adopted. The DSM approach for columns is based on existing buckling curves and provides accurate resistance predictions for slender and stocky cross-sections. The proposed DSM approach for beam-columns also improves capacity predictions for stocky and slender cross-sections obtained from the traditional methods for different bending moment distributions. This is attributed to the fact that the beam-column behaviour is directly calculated with a unique strength curve, considering the member and section slendernesses based on the elastic instabilities of the section subjected to the actual stress distribution instead of calculating the compressive and flexural strengths independently and combining these through an interaction equation, as is the traditional uncoupled approach. Finally, a reliability study of the full slenderness range DSM approach is presented to determine resistance factors for the different stainless steel grades columns and beam-columns
von Boetticher, A.; Turowski, J.; McArdell, B.W.; Rickenmann, D.; Hurlimann, M.; Scheidl, C.; Kirchner, J. Geoscientific model development Vol. 10, num. 11, p. 3963-3978 DOI: 10.5194/gmd-10-3963-2017 Data de publicació: 2017-11 Article en revista
Here, we present validation tests of the fluid dynamic solver presented in von Boetticher et al. (2016), simulating both laboratory-scale and large-scale debris-flow experiments. The new solver combines a Coulomb viscoplastic rheological model with a Herschel-Bulkley model based on material properties and rheological characteristics of the analyzed debris flow. For the selected experiments in this study, all necessary material properties were known - the content of sand, clay (including its mineral composition) and gravel as well as the water content and the angle of repose of the gravel. Given these properties, two model parameters are sufficient for calibration, and a range of experiments with different material compositions can be reproduced by the model without recalibration. One calibration parameter, the Herschel-Bulkley exponent, was kept constant for all simulations. The model validation focuses on different case studies illustrating the sensitivity of debris flows to water and clay content, channel curvature, channel roughness and the angle of repose. We characterize the accuracy of the model using experimental observations of flow head positions, front velocities, run-out patterns and basal pressures.
The advances in information and communication technologies led to a general trend towards the availability of more detailed information on dam behaviour. This allows applying advanced data-based algorithms in its analysis, which has been reflected in an increasing interest in the field. However, most of the related literature is limited to the evaluation of model prediction accuracy, whereas the ulterior objective of data analysis is dam safety assessment. In this work, a machine-learning algorithm (boosted regression trees) is the core of a methodology for early detection of anomalies. It also includes a criterion to determine whether certain discrepancy between predictions and observations is normal, a procedure to compute a realistic estimate of the model accuracy, and an original approach to identify extraordinary load combinations. The performance of causal and noncausal models is assessed in terms of their ability to detect different types of anomalies, which were artificially introduced on reference time series generated with a numerical model of a 100-m-high arch dam. The final approach was implemented in an online application to visualise the results in an intuitive way to support decision making.
El objeto de este estudio consiste en la construcción y calibración de un modelo numérico para la simulación de la dinámica sedimentaria del tramo de río Ebro comprendido entre los puentes de la N-113 y de la autopista AP-15 en Castejón, para su posterior aplicación a otros tramos del mismo río.
Se ha analizado numéricamente mediante el modelo Iber la dinámica sedimentaria del tramo del río cuyas batimetrías se obtuvieron durante las campañas anterior y posterior a las importantes avenidas que tuvieron lugar entre enero y marzo de 2015.
Una vez incorporada la geometría del cauce al modelo, se han simulado los caudales circulantes en el período comprendido entre las dos batimetrías y la evolución del cauce así obtenida se ha comparado con la que muestra la diferencia entre ambas batimetrías, lo que ha permitido calibrar los parámetros del modelo.
Mediante el modelo calibrado se dispone ahora de una herramienta que permite reproducir la dinámica sedimentaria de un tramo del río Ebro. Esta herramienta puede resultar útil para poder describir el comportamiento de otros tramos del mismo río.