Dams and overtopping: a polyhedral relationship

This paper discusses the different elements playing a role in causes and consequences of dam overtopping: the river basin, the reservoir, the dam and the spillway, the riverbed and the territory downstream of the reservoir. The risk is presented as the key concept linking all these elements, causes and consequences of the dam overtopping. The perspective of the different stakeholders is also considered, especially that of the dam owner, who is responsible for making a decision about what to do if a dam overtopping problem arises. The different attitudes of the dam owner are mainly characterized by the definition of the damage adopted when considering the risk as a basis for an informed decision taking. The social and economical risk are defined as characteristic of the extreme opposite positions, considering only damage to others, casualties and environmental damage (social risk), or considering only the cost for the dam owner, including cost in compensation for casualties and environmental damage, (economical risk). The legalist position is also considered, of the dam owner that seeks to comply with the regulations, irrespective of the risk except in the countries where risk considerations are already part of the legal framework for decision-making. Three key questions that the dam owner must answer to solve an overtopping problem are analyzed: a) Do I really have a problem? b) What different ways can I solve my overtopping problem; and, c) How do I choose the best solution for me? Finally, an ideal process for solving an overtopping problem on a rational and informed way is proposed, including the perspective and position of the particular dam owner. The general process should be adapted for every particular case in order to be feasible in practice and as efficient as possible

Los aliviaderos tipo laberinto. Un nuevo enfoque para su cálculo hidráulico

At present, The Poiythencic University of Madr id, the CEDEX and JESÚS GRANELL ingenieros Consultores Company are carrying out an investigation project on labyrinth spillways. As a part of this project, it is proposed a new method for the hydraulic calculation of this type of spillways, which is based on the main facts occurred: the obliquity of the diagonal faces of the weir referred to the direction of the flow upstream in the approximation, and the nappe interference. The method is going to be improved a nd validated by physical a nd numerical modelling as a pa rt of the investigation project. However, the comparison of its preliminary results with other methods, and also with some physical models available provides encouraging results

IMM-Based lane-change prediction in highways with low-cost GPS/INS

The prediction of lane changes has been proven to be useful for collision avoidance support in road vehicles. This paper proposes an interactive multiple model (IMM)-based method for predicting lane changes in highways. The sensor unit consists of a set of low-cost Global Positioning System/inertial measurement unit (GPS/IMU) sensors and an odometry captor for collecting velocity measurements. Extended Kalman filters (EKFs) running in parallel and integrated by an IMM-based algorithm provide positioning and maneuver predictions to the user. The maneuver states Change Lane (CL) and Keep Lane (KL) are defined by two models that describe different dynamics. Different model sets have been studied to meet the needs of the IMM-based algorithm. Real trials in highway scenarios show the capability of the system to predict lane changes in straight and curved road stretches with very short latency times.Ministerio de Fomento: FOM/2454/200

A systematic assessment of the influence of geometry and materials properties on the performance of arch dams

Arch dams have different properties that play a relevant role in their behavior, although it is not clear to what degree or in what sense. There is some consensus regarding the relevance of certain factors such as length at crown, height, base and crest thickness, or Young modulus of dam and foundation. However, others such as the shape of arcs and cantilevers, which are correlated and whose effect is more difficult to consider, can also be influential. In this work, a systematic study of the response of arch dams in front of the common loading scenarios has been carried out, taking into account the usual range of variation of their properties. In total, 39 input variables related to geometry, material strength and thermal load were considered. Ranges of variation for each of these parameters have been defined according to the usual design criteria and 3,000 different geometries – together with the corresponding FEM models have been generated with random values of these parameters. The resulting displacements and stresses have been used to fit prediction models based on a machine learning technique named ‘random forests’ that give an estimate of the dam response. The interpretation of these models can be associated with the relative importance of the characteristics of arch dams on each of the behavior variables

Análisis de filtración en presas con cimientos yesíferos

El emplazamiento de presas en España es cada vez más restringido y las características geológicas y geotécnicas del cimiento no siempre tan favorables como se desearía. En el caso de cimientos yesíferos, es necesario proyectar una sección tipo de presa que limite, dentro de valores aceptables, el proceso de disolución del cimiento. El objetivo es modelizar el proceso de disolución del cimiento debido a la filtración, determinando el correspondiente cambio de permeabilidad de éste y el consiguiente aumento de los caudales de filtración. Para ello se ha desarrollado un programa en Visual Basic (denominado DISOLUCION2D) que realiza un cálculo iterativo en el tiempo, a partir de los resultados del programa comercial SEEP2D, de cálculo de redes de filtración mediante elementos finitos. Se han realizado ensayos, para comprobar la validez de las formulaciones. Se han calculado modelos presa-cimiento con distintos diseños de presa y características del cimiento (porcentaje de material soluble, profundidad y espesor de la capa yesífera, permeabilidades iniciales, ...) para concluir qué factores son determinantes

Consideraciones para la investigación simbólica en Diseño desde los sistemas complejos

La teoría de sistemas complejos proporciona la comprensión de límites, estructuras y procesos disciplinarios a la investigación en Diseño. La incertidumbre es precursora de la complejidad de la información, observada en espirales rizomáticas para hallar las articulaciones organizacionales en cadena como poiesis. La organización es orden y desorden y media la interacción de objetos, sujetos, procesos, límites y estructuras. La interacción es generadora de formas y organización involucrando el punto de vista del investigador que se desplaza aleatoriamente permitiendo recodificar el concepto, amén del entorno que otorga vida al evento particular de la investigación.The theory of complex systems provides the understanding of boundaries, structures and disciplinary processes to design research. The uncertainty is a precursor of the complexity of the information, observed in rhizomatic spirals to find the organizational articulations in chain like poiesis. Organization is order and disorder and mediates the interaction of objects, subjects, processes, limits and structures. Interaction is a generator of forms and organization involving the point of view of the researcher who moves randomly, allowing recoding the concept, in addition to the environment that gives life to the particular event of the research.A teoria de sistemas complexos fornece a compreensão de fronteiras, estruturas e processos disciplinares para projetar a pesquisa. A incerteza é um precursor da complexidade da informação, observada nas espirais rizomáticas para encontrar as articulações organizacionais em cadeia como a poiesis. A organização é ordem e desordem e media a interação de objetos, sujeitos, processos, limites e estruturas. A interação é um gerador de formas e organização envolvendo o ponto de vista do pesquisador que se movimenta de forma aleatória, permitindo recodificar o conceito, além do ambiente que dá vida ao evento particular da investigação

PROYECTO DE TESIS - Análisis de las Noticias Periodísticas de los juegos Paralímpicos Río 2016 del diario digital Todo Sport según la teoría del Encuadre

Los Juegos Paralímpicos celebrados por primera vez en el año 1960, representan una de las actividades de competencia deportiva más grande para personas con discapacidad que viene creciendo cada cuatro años. Según el Comité Paralímpico Español, en los últimos Juegos de Río 2016, fueron 23 deportes presentados frente a 42 en los Juegos Olímpicos. Asimismo, fueron 528 pruebas para los para deportistas, frente a 306 para los deportistas olímpicos. En cuanto a lugares donde se llevaron a cabo estos juegos: 20 sedes fueron destinadas para los juegos Para deportivos y 37 para los olímpicos. 176 países participaron con para deportistas, y 205 países albergaron los juegos tradicionales. Un aspecto importante es la cantidad de deportistas para cada tipo de jugadores, mientras que son 4250 para deportistas, 11741 son atletas de los juegos Olímpicos. Debido a estas grandes diferencias en estas áreas, los Juegos Paralímpicos no reciben el mismo interés que los Juegos Olímpicos.Trabajo de investigacio

Energy Dissipation of Highly Convergent Chutes in Stilling Basins of Concrete Dams

This article presents the results of a combination of experimental and numerical research on the performance of stilling basins of spillways with highly convergent chutes (HCC). The comparison between the energy dissipation of the stilling basins with flat slab and baffle blocks shows that the latest are more efficient. Because of that, the cost savings of using such blocks can be significant. The results obtained could be applied in different cases such as increasing the capacity of existing spillways and protecting dams against overtopping. The application of HCC spillways in new dams could lead to a reduction in the cost of the stilling basin compared to conventional hydraulic jump energy dissipators

Aliviaderos tipo laberinto y en tecla de piano

Las conferencias presentadas durante la Jornada Técnica sobre Avances en investigación aplicada en seguridad hidráulica de presas organizada por el Centro de Estudios Hidrográficos del CEDEX y la Universidad Politécnica de Madrid el mes de junio de 2013 versan sobre la mejora de la seguridad hidráulica de las presas, una materia de especial importancia en nuestro país (habida cuenta del elevado número de infraestructuras de regulación en servicio y de su antigüedad media) y constituye una tarea en la que tanto el CEDEX como la Universidad Politécnica de Madrid han trabajado activamente en los últimos años. El Departamento de presas de la ETSICCP, el Centro de Estudios Hidrográficos del CEDEX el Centro Internacional de Modelación Numérica (CIMNE), la empresa VEMSA y la compañía de ingeniería JESÚS GRANELL Ingenieros Consultores viene acometiendo un proyecto de investigación en materia de vertederos tipo laberinto. El objetivo principal de la investigación es la obtención de conocimientos y herramientas que permitan un diseño razonado de este tipo de estructuras hidráulicas. Además, se estudian otros efectos en su comportamiento, como son las condiciones hidráulicas de aproximación a la embocadura. La investigación se basa en el ensayo hidráulico en modelos físicos complementado por modelos numéricos mediante aplicaciones de última generación. Descripción del proceso de diseño y construcción del modelo

Interpretation of dam deformation and leakage with boosted regression trees

Predictive models are essential in dam safety assessment. They have been traditionally based on simple statistical tools such as the hydrostatic-season-time (HST) model. These tools are well known to have limitations in terms of accuracy and reliability. In the recent years, the examples of application of machine learning and related techniques are becoming more frequent as an alternative to HST. While they proved to feature higher flexibility and prediction accuracy, they are also more difficult to interpret. As a consequence, the vast majority of the research is limited to prediction accuracy estimation. In this work, one of the most popular machine learning techniques (boosted regression trees), was applied to model 8 radial displacements and 4 leakage flows at La Baells Dam. The possibilities of model interpretation were explored: the relative influence of each predictor was computed, and the partial dependence plots were obtained. Both results were analysed to draw conclusions on dam response to environmental variables, and its evolution over time. The results show that this technique can efficiently identify dam performance changes with higher flexibility and reliability than simple regression models