Spanish Dams Research Articles

8. Western Europe

Editorial note: Due to unforeseen circumstances, we were unable to include the 2019 report in last year’s volume, and, for that reason, it is included here. 2019 Report On 8 January, the Portuguese Republic deposited its instrument of accession to the 2001 International Convention on the Control of Harmful Anti-fouling Systems on Ships. Entry into force occurred on 8 April. Two main issues remain critical for international river basins: water quantity and quality. Minimum water flows delivered by Spanish dams, although in compliance with the 1998 Convention on the Co-operation for the Protection and Sustainable Use of the Water Resources of the Portuguese–Spanish River Basins (Albufeira Convention), do not qualify as adequate from an ecological water flow perspective. Poor water quality reaching the international border remains a serious problem, especially in the Tagus and Guadiana river basins. During the summer of this year,...

Comprehensive decision-making approach for managing time dependent dam risks

Dams are critical infrastructures whose safety must be properly managed. Traditional decision-making approaches often assume the stationarity of factors defining risk. However, dam risk is susceptible to evolve with time. Risk can no longer be considered a static but a time-dependent concept which cumulative value must be reduced for different timescales. A broader perspective to dynamically evaluate time issues in the prioritization of measures is thus required.A new approach is proposed for dam risk management in the long term that considers the potential evolution of risk. A new time-dependent risk indicator that allows assessing the efficiency of adaptation measures in optimally reducing dam risks has been defined: the Aggregated Adjusted Cost per Statistical Life Saved (AACSLS). Its use makes it possible to better design risk reduction measures and to plan the implementation sequence that maximizes their effectiveness.The methodology has been applied to the case study of a Spanish dam under the effects of climate change. Different risk reduction measures have been proposed and their effects have been analyzed for a specific time horizon. The use of the AACSLS indicator has allowed identifying the prioritization of measures that optimizes the allocation of economic resources in the long term.

Quantification of climate change impact on dam failure risk under hydrological scenarios: a case study from a Spanish dam

Abstract. Dam safety is increasingly subjected to the influence of climate change. Its impacts must be assessed through the integration of the various effects acting on each aspect, considering their interdependencies, rather than just a simple accumulation of separate impacts. This serves as a dam safety management supporting tool to assess the vulnerability of the dam to climate change and to define adaptation strategies under an evolutive dam failure risk management framework. This article presents a comprehensive quantitative assessment of the impacts of climate change on the safety of a Spanish dam under hydrological scenarios, integrating the various projected effects acting on each component of the risk, from the input hydrology to the consequences of the outflow hydrograph. In particular, the results of 21 regional climate models encompassing three Representative Concentration Pathways (RCP2.6, RCP4.5 and RCP8.5) have been used to calculate the risk evolution of the dam until the end of the 21st century. Results show a progressive deterioration of the dam failure risk, for most of the cases contemplated, especially for the RCP2.6 and RCP4.5 scenarios. Moreover, the individual analysis of each risk component shows that the alteration of the expected inflows has the greater influence on the final risk. The approach followed in this paper can serve as a useful guidebook for dam owners and dam safety practitioners in the analysis of other study cases.

Los think tanks y su presencia en la agenda mediática española/ Think tanks and their presence in the Spanish media agenda

ResumenEl estudio que se expone a continuación intenta abordar el papel que tienen los think tanksen la prensa española. Los laboratorios de ideas centran su actividad en crear y reformular ideas con el objetivo de difundirlas a la opinión pública y que esta las acoja y las tomen como propias, la mayor parte de estas enfocadas al ámbito político. Por tanto, los medios de comunicación tienen un papel fundamental en el desarrollo de estas organizaciones. Para la consecución de los objetivos de este estudio se ha realizado una revisión bibliográfica a fondo del tema expuesto y, además, se desarrolla una metodología cuantitativa a través de un análisis de contenido de los cuatro periódicos con mayor promedio de difusión según la Oficina de Justificación de la Difusión (OJD). Gracias a la aplicación de esta metodología se han obtenido resultados y conclusiones sobre la relación entre los laboratorios de ideas y los medios de comunicación en España. Todo esto, junto al planteamiento de la pregunta de investigación: ‘Los think tanksespañoles difunden su actividad y sus ideas a través de medios de comunicación afines a su ideología política, situándose en la misma posición del espectro político’. La presencia, las estrategias y las técnicas que estas organizaciones utilizan para la difusión de su actividad son algunas de las secciones que este estudio expone. Asimismo, se obtienen conclusiones acerca de nuevos think tanksespañoles que han irrumpido en la presa, como Politikón y sus relaciones con el periódico El País, abriendo futuras líneas de investigación. Palabras clave:Think tanks, laboratorios de ideas, medios de comunicación, prensa española, relaciones públicas. AbstractThe following study attempts to address the role of think tanks in the Spanish press. These institutions focus their activity on creating and reformulating ideas with the aim of disseminating them to the public opinion and that the latter welcomes them and takes them as its own, most of these are focused on the political themes. In addition, the information provided by think tanks that have greater participation and, therefore, appearances in the media, are characterized by achieving greater legitimacy. Therefore, the media have a fundamental role in the development of these organizations. In order to achieve the objectives of this study, an in-depth bibliographic review of the subject has been carried out, dealing with different areas that are found around these think tanks: definition, typologies, functions, objectives and the importance of communication for these institutions. It has also focused later on contextualising and characterising how these institutions are and how they carry out their activity in Spain, as the study seeks to focus on the Spanish reality. In the same way, in order to obtain a more faithful image of the state of think tanks in the Spanish territory, a quantitative methodology has been developed through an analysis of the content of the four newspapers with the highest average circulation according to the Oficina de Justificación de la Difusión(OJD): El País, La Vanguardia, El Mundoand ABC, by means of a systematic random k-ima sampling consisting of periods of seven days. Thanks to the application of this methodology, results and conclusions have been obtained regarding the relationship between think tanks and the media in Spain. All this, together with the research question: Do Spanish think tanks disseminate their activity and ideas through media related to their political ideology, placing themselves in the same position of the political spectrum?, which has allowed to develop results and conclusions about the possible ideological affinity between media and laboratories of Spanish ideas. The presence, the strategies and the communication techniques that these organisations use to disseminate their activity become an axis of great importance and, therefore, of relevance to the field of communication. It should also be mentioned that this study has been able to draw conclusions about new Spanish think tanks that have broken into the Spanish dam, such as Politikón and its relations with the newspaper El Paísor the characteristic case found between the newspaper ABCand the think tanks Instituto de Estudios Regionales y Metropolitanos de Barcelona, since the newspaper accuses of having privileges thanks to the affinity of the institution with the mayoress of Barcelona. Thanks to the discussion and conclusions of this study, future lines of research are opened up, as the phenomenon of idea laboratories continues to develop in Spain. Keywords:Think tanks, ideas laboratories, media, Spanish press, Public Relations.

An Interactive Tool for Automatic Predimensioning and Numerical Modeling of Arch Dams

The construction of double-curvature arch dams is an attractive solution from an economic viewpoint due to the reduced volume of concrete necessary for their construction as compared to conventional gravity dams. Due to their complex geometry, many criteria have arisen for their design. However, the most widespread methods are based on recommendations of traditional technical documents without taking into account the possibilities of computer-aided design. In this paper, an innovative software tool to design FEM models of double-curvature arch dams is presented. Several capabilities are allowed: simplified geometry creation (interesting for academic purposes), preliminary geometrical design, high-detailed model construction, and stochastic calculation performance (introducing uncertainty associated with material properties and other parameters). This paper specially focuses on geometrical issues describing the functionalities of the tool and the fundamentals of the design procedure with regard to the following aspects: topography, reference cylinder, excavation depth, crown cantilever thickness and curvature, horizontal arch curvature, excavation and concrete mass volume, and additional elements such as joints or spillways. Examples of application on two Spanish dams are presented and the results obtained analyzed.

Modelación física y numérica de aliviaderos en laberinto con fondo poliédrico

<p class="Resumen">Un número importante de presas en España deben ampliar sus aliviaderos para cumplir criterios de seguridad distintos a los de su construcción. En este contexto, cobran interés soluciones de aliviaderos no convencionales como los aliviaderos en laberinto, que permiten aumentar la capacidad de desagüe de estructuras existentes con una inversión moderada. Para la optimización del diseño de este tipo de aliviaderos se desarrolla el proyecto POLILAB, en cuyo marco se llevaron a cabo las campañas de modelación física y numérica que se exponen en este artículo. Se describen los resultados más relevantes en lo relativo a la inclusión de fondos poliédricos en aliviaderos en laberinto como refuerzo estructural, contemplando además las modificaciones que implican con respecto a soluciones en laberinto con fondo plano, en lo relativo a capacidad de desagüe, patrón de flujo y acciones hidrodinámicas sobre los contornos del laberinto.</p>

Fentes documentales gráficas para el estudio de los pretéritos paisajes fluviales: los proyectos españoles de presas y embalses.

E este trabajo se analizan las características que hacen de las fuentes documentales gráficas, incorporadas en los proyectos españoles de presas y embalses, uno de los pilares más importantes para el estudio de los paisajes fluviales de nuestro pasado inmediato. El examen de los mapas, planos, climo-diagramas, hidrogramas, gráficos de sondeos e imágenes fotográficas, etc., que acompañan a los informes técnicos, constituyen una objetiva representación y visualización de una realidad geográfica mutante en el tiempo. Además, su contraste diacrónico permite establecer una secuencia de acontecimientos —naturales y antrópicos— en los ámbitos de las vertientes y fondos de valle que, en muchos casos, sorprende por la intensidad de las transformaciones del paisaje en tan breve lapso de tiempo.

Influence of carbonate content of marls used in dams: Geotechnical and statistical characterization

The relationships between geotechnical parameters identified from tests of slake durability, swelling behavior, soil dispersion, and consolidation, using samples of marls utilized to build impervious cores of Spanish dams, were analyzed. The analyses have determined the incidence of the processes of internal erosion and piping, self-stability, strength, durability (behavior during dry–wet cycles) and their variation with the carbonate content of marls.A total of 118 samples were selected from marl quarries used for the construction of three impervious cores of dams. The carbonate content of the samples varied from less than 10% to more than 70%. The type and amount of clay also varied. The results show that the carbonate content alters the short-term to medium-term cohesion of soils by the effect of possible cementation and break-up. The medium–low correlation indexes found in this work (although acceptable) are due to the complex mechanics of the durability and dispersibility phenomenons.

Carcass yield traits of kids from a complete diallel of Boer, Kiko, and Spanish meat goat breeds semi-intensively managed on humid subtropical pasture1,2

Bucklings (n = 275) from a complete diallel of Boer, Kiko, and Spanish meat goats were slaughtered at 7 mo of age (4 mo postweaning) to evaluate genetic effects on carcass yield. Breed of sire did not affect (P > 0.05) live, carcass, and primal weights. Conversely, breed of dam was a consistently significant source of variation for carcass weight traits. Kiko dams produced kids with heavier (P < 0.05) live, carcass, and primal weights than Boer dams. Weights from Spanish dams were intermediate to Boer and Kiko with the significance of differences varying by trait. Cold carcass dressing percent was affected (P < 0.01) by breeds of sire and dam. Boer sires decreased (P < 0.05) dressing percent compared with Kiko and Spanish sires. Dressing percent was also less (P < 0.01) from Boer dams than from Kiko dams; Spanish dams were intermediate and did not differ (P > 0.05) from Boer or Kiko. Subjective conformation scores for muscularity were affected (P < 0.01) by breeds of sire and dam. Boer-sired kids had better (P < 0.01) live scores than Kiko-sired kids. Progeny of Boer dams had better (P < 0.05) live scores than progeny of Spanish dams. Boer-sired kids also had better carcass scores (P < 0.05) than Kiko-sired and Spanish-sired kids. Breed differences for primal cut proportions were negligible. Proportional boneless meat yields did not vary (P > 0.05) by breeds of sire or dam. Direct effects of Boer were negative for carcass weight, dressing percent, and shoulder weight and positive for proportional leg weight. Direct effects of Kiko were positive for carcass weight and shoulder weight and negative for proportional leg weight. Direct effects of Spanish did not differ (P > 0.10) from 0 for any trait tested. Heterosis levels were similar among breed pairings. Heterosis was substantial (P ≤ 0.05) for live, carcass, and primal weights (5 to 9%) but not for dressing percent, proportional boneless meat yield, or primal weight proportions (<2%). Significant genetic variation was observed among goat breeds for carcass yield traits. Dam breed was more influential than sire breed. Boer germplasm was not superior to Kiko or Spanish germplasm for carcass yield when semi-intensively managed on humid, subtropical pasture. Results emphasize the importance of comparative breed evaluations to provide industry with reliable information on carcass yield among goat genotypes.

Birth to weaning kid traits from a complete diallel of Boer, Kiko, and Spanish meat goat breeds semi-intensively managed on humid subtropical pasture1,2

Boer, Kiko, and Spanish meat goats were semi-intensively managed in a complete 3-breed diallel mating scheme to evaluate genetic effects on preweaning kid performance. Over a 6-yr period, 1,547 kids were born in March and May with 1,173 kids raised by their dams to weaning at 3 mo of age. March-born kids were lighter (P < 0.01) at birth, but had greater (P < 0.01) preweaning ADG and survival rates and heavier (P < 0.01) weaning weights than May-born kids. For birth weight, the direct Boer effect was positive (P < 0.01) and direct effects were negative (P < 0.01) for Kiko and Spanish. The direct Kiko effect for preweaning ADG was positive (P < 0.05), whereas other direct breed effects for ADG and all direct effects for weaning weight did not differ from 0 (P > 0.10). Maternal Boer effects were negative (P < 0.01) for birth weight and weaning weight, whereas maternal Kiko effects were significantly (P < 0.05) positive for preweaning ADG and weaning weight. Maternal Spanish effect was positive (P < 0.05) for birth weight, but did not differ from 0 (P > 0.5) for preweaning ADG or weaning weight. Heterosis for birth weight was exhibited (P < 0.01) for each pair of breed crosses, but only between Boer and Kiko for ADG and weaning weight. Kiko and Spanish dams had greater (P < 0.01) preweaning kid survival rates than Boer dams, but the former 2 did not differ (P = 0.72). Significant genetic variation was observed between meat goat breeds for kid performance to weaning. Maternal breed effects were more influential than direct breed effects. Boer goats were not superior to Kiko or Spanish for preweaning kid performance when semi-intensively managed on humid, subtropical pasture. Kiko should be a preferred breed and to a lesser extent Spanish for enhancing birth to weaning kid performance. Findings of this study emphasize the importance of proper doe breed selection in achieving desired kid performance to weaning in meat goats.

Reproductive and health traits among Boer, Kiko, and Spanish meat goat does under humid, subtropical pasture conditions of the southeastern United States12

Boer (n = 132), Kiko (n = 92), and Spanish (n = 79) straightbred does were studied across 6 yr to assess doe fitness on southeastern US pastures. Does were exposed to Boer, Kiko, and Spanish bucks in a complete 3-breed diallel mating scheme each fall for spring kidding in March or May. A total of 1,041 doe-yr units were observed with does (ranging from 2 to 8 yr of age) managed together in a semi-intensive manner. The proportion of buck-exposed does delivering at least 1 live kid was less (P < 0.01) for Boer does (80%) than for Kiko (96%) and Spanish does (94%). Litter size and litter weight at birth were not affected (P > 0.15) by breed of dam. By weaning at 3 mo, the proportion of available does weaning at least 1 kid was less (P < 0.01) for Boer does (53%) than for Kiko (84%) and Spanish does (82%). For does weaning kids, litter size at weaning was greater (P = 0.01) for Spanish does (1.74 kids) than for Kiko (1.59 kids) and Boer does (1.47 kids). Litter weaning weight was lighter (P < 0.01) for Boer dams (23.0 kg) than for Kiko (27.2 kg) and Spanish dams (26.5 kg). The efficiency ratio of litter weight to dam weight at weaning differed (P < 0.05) among all 3 dam breeds: Boer = 51%; Kiko = 62%; Spanish = 68%. Annual rates of lameness, endoparasitism, and attrition, respectively, were greater (P < 0.01) for Boer does (69, 53, and 28%) than for Kiko (32, 24, and 10%) and Spanish does (42, 22, and 11%). Postpartum fecal egg counts for endoparasite loads were less (P < 0.05) for Spanish dams (346 eggs/g) than for Kiko (524 eggs/g) and Boer does (675 eggs/g). Whole-herd annual doe productivity based on all available does was less (P < 0.01) for Boer does (11.7 kg weaned/doe) compared with Kiko (22.0 kg weaned/doe) and Spanish does (21.1 kg weaned/doe). Boer does expressed substantially decreased levels of fitness compared with Kiko and Spanish does when semi-intensively managed on humid, subtropical pasture. Kiko and Spanish should be preferred as maternal breeds in meat goat production systems under conditions reflective of this study.

Comparative study of the alkali-silica reaction (ASR) in granitic aggregates

The reaction between certain reactive components of aggregates (like opal and metaestable silica) and concrete pore solution is well documented. Nevertheless, in this study it has been shown that some aggregates, like granite, could develop a rapid or slow alkali-silica reaction (ASR) depending on the deleterious component involved. Mortar bars were cast with two granitic aggregates extracted from concrete cores drilled in two Spanish Dams affected by ASR, being classified as granitic rocks. The main difference between them is the reactive component: microcrystalline quartz in one case and strained and microcracked quartz in the other case. A petrographic examination was carried out in the mortar bars. Thin sections were cut and the alkalisilica gel was stained for an easier detection. Then, the thin sections were examinated with a stereomicroscope comparing the differences in the progress of the ASR for both aggregates. It can be concluded that the main mechanism of formation and storage of gel is associated to the micro-cracks instead of the subgrain boundaries.

Comparison of ASR-gels in concretes against accelerated mortar bar test samples

Through scanning electron microscopy and local chemical analysis by energy-dispersive X-ray spectroscopy, alkali–silica reaction (ASR) products in two Spanish dam concretes and accelerated mortar bar test samples (UNE 146508:1999) were compared. In chemical composition, gels formed in the accelerated test revealed marked differences to gels formed in concrete. Higher sodium and lower calcium and potassium contents were especially noteworthy in mortar bar test samples. Further, very marked, contrary tendencies in the evolution of chemical composition between gels formed in concrete and those formed in the accelerated mortar bar test were observed. In mortar samples, enrichment in sodium and impoverishment in calcium, among later gel generations, related to progressive ASR development, is characteristic. Real concretes show a contrary tendency; later phases of gel become markedly enriched in calcium. The differences observed may lead to variations in aggregate behaviour in accelerated test and in field performance in concretes.

Les ruptures de barrages dans le monde : un nouveau bilan de Potosi (1626, Bolivie)

(2002). Dam collapses in the world : a new estimation of the Potosi disaster (1626, Bolivia) La Houille Blanche: Vol. 88, No. 4-5, pp. 165-170.

Age at first estrus, ovulation rate, and age at anestrus in puberal Boer×Spanish and Spanish does

Sixty doe kids from Spanish dams and Boer ( n=6) or Spanish ( n=6) sires were used to evaluate selected reproductive traits. Using plasma progesterone concentrations, first estrus was detected at 7.7 and 7.5 months of age in Boer×Spanish (BS), and Spanish×Spanish (SS) doe kids, respectively. Body weights (BW) at first estrus were 45% (BS), and 50% (SS) of BW at 18 months of age. Onset of anestrus occurred at 11.3 and 11.4 months of age for BS and SS does, respectively. BS does had an ovulation rate of 1.24, as compared to 1.27 for SS does. Breed, BW nearest first estrus, and birth date were not significant sources of variation for reproductive traits. Age at first estrus was four months greater in twin-born does relative to single-born does. No significant differences were found between BS and Spanish does for age at first estrus, ovulation rate, and age at anestrus. The results indicate that BS crossbred does are similar to Spanish does for female reproduction.

Deformability of foundations of some Spanish dams. —Case studies : GUERREIRO, M PROCEED. 2 CONGRESS, INTERNAT. SOC. ROCK MECH. BELGRAD, 1970, V4, 1974, P634–P636

Deformability of foundations of some Spanish dams. —Case studies : GUERREIRO, M PROCEED. 2 CONGRESS, INTERNAT. SOC. ROCK MECH. BELGRAD, 1970, V4, 1974, P634–P636

El impacto de la sequía en la política hidráulica española desde 1850 a 1975. Algunos datos sobre el pantano de los Barrios de Luna (León)

El vocablo “sequía” ha sido común en la historia de España. A mitad del siglo XIX, comenzó a circular la opinión de que el agua debía ser propiedad del Estado y debía aprovecharse para irrigar amplias superficies que estaban esperando este recurso y que no se perdiera en el mar sin fertilizar antes los campos. Los proyectos para construir pantanos proceden precisamente de esta necesidad. Iniciar esta tarea necesitó de una nueva normativa legal y en 1889 se promulgó el primer Código Civil y se pudo complementar la Ley de Aguas de 1879. Entre los años 2015 y 2017 las lluvias han estado ausentes de los paisajes españoles y los pantanos, por lo que las esperanzas gestadas hace cincuenta años o más se están esfumando. El impacto de la sequía está presente en todas las cuencas; es más, se encuentran casi sin recursos hídricos. Esta realidad ha generado alarma social y, de persistir, saltará a la política. Este ensayo aborda la sequía y la falta de agua como problema en el último siglo y medio de la historia de España, desde 1850.

Structural Response Of A Dam-foundation Rock-Impounded Water Model Under Seismic AndThermal Loading

In this paper a comprehensive study of the existing Spanish dam of Bolarque is presented. The dam was composed of two different classes of concrete and also two choices of material characteristic of the rock foundation were considered. The seismic analysis was earned out taking in account the dam-foundation rockimpounded water interaction. Additionally, thermal loadings were included by using an equivalent structural model. Overall 128 structural analyses were carried out to complete consider the necessary combinations of materials, seismic and thermal loadings. Numerical results are presented showing the behaviour of the dam under the worst situations for empty and full reservoir. 1 . A BRIEF HISTORY OF BOLARQUE DAM The Bolarque dam was built in 1910 and works to increase its height and therefore to improve the volume of impounded water were carried out in 19541955. Figure la shows the cross-section of the dam and Figure Ib the structural model which acommodate quite properly the actual geomeuy. Transactions on the Built Environment vol 20, © 1996 WIT Press, www.witpress.com, ISSN 1743-3509