Comparative predictions of the end of construction performance of a central core embankment dam located in southern Portugal are presented. The predictions are based on finite element analyses, one set being carried out at Swansea and the other at the Laboratório Nacional de Engenharia Civil (LNEC) in Lisbon. Except for collaboration over the interpretation of laboratory test results the work was independent. Different analytical models were used at the two centres: the ‘KG’ model at Swansea and one based partly on the ‘hyperbolic’ model of Duncan and Chang at LNEC. The analytical work leading to the predictions was completed by the early stages of the dam's construction thus making them class A. The Paper starts with a description of a four-year laboratory research programme at LNEC to determine the properties of the fill materials. This involved novel large-scale one-dimensional and triaxial testing. Predictions of settlements and total stresses from the two models are presented at instrument locations. Useful comparisons between the models are obtained. This Paper will be followed later with a Technical Note comparing predictions and measurements. L'article présente des prévisions comparatives du comportement à la fin de la construction d'un barrage en terre avec un noyau central au Portugal du sud. Ces prévisions sont basées sur des analyses par éléments finis effectuées d'un côté à Swansea et de l'autre côté au Laboratôrio Nacional de Engenharia Civil (LNEC) à Lisbonne. Ces deux recherches étaient indépendantes l'une de l'autre, à l'exception d'une collaboration dans l'interprétation des résultats des essais faits en laboratoire. On a utilisé des modèles analytiques différents, le modèle K–G à Swansea et un modèle basé en partie sur le modèle hyperbolique de Duncan et Chang au LNEC. Les prévisions étaient de catégorie A, parce qu'on a complété le travail analytique qui les a précédées au cours des premières étapes de la construction du barrage. L'article commence par décrire le programme de recherches dans le laboratoire qui a été suivi pendant quatre années au LNEC pour déterminer les propriétés des matériaux de remblayage. Cette procédure comprenait de nouveaux essais unidimensionnels et triaxiaux de grand envergure. Des prévisions de tassements et de contraintes totales déduites des deux modèles sont présentées pour les emplacements des instruments et des comparaisons utiles sont obtenues. On a l'intention de publier plus tard une note technique qui comparera les prévisions et les mesures.

A back–analysis of the Beliche Dam in southern Portugal is described. This dam was the subject of a 'Class A' prediction which grossly under–predicted the actual settlement at the end of construction. The analysis described here, which incorporated an elasto–plastic critical state model applied in terms of effective stress, simulated the effect of collapse settlement and by so doing reproduced a maximum settlement which was close to that measured. The earlier underprediction is attributed mainly to the fact that that analysis did not include the collapse settlement due to the partial impounding of the reservoir which occurred before construction was complete. The back–analysis described here covers the period from the start of construction in 1984 to approximately four years after the first complete impounding in January 1988. Comparisons are made between the calculated and measured movements and stresses. Apart from the good agreement with the maximum recorded settlement, the measured settlements generally exceeded the calculated values. Part of the underprediction of settlements is attributed to creep which the modelling did not attempt to simulate and part to the in situ relative density being less than that used in the tests from which the parameters were determined. The computed stress distributions indicated a favourable load transfer from shell to core, thus confirming the safety of the dam against internal erosion due to hydraulic fracture. It was, however, possible to estimate from the settlement records how much of the settlement is due to creep, and this has been done. The conclusions underline the usefulness of the collapse settlement methodology. L'exposé décrit une analyse rétrospective du barrage de Beliche dans le sud du Portugal. Ce barrage avait fait l'objet d'une prédiction de classe A», qui a considérablement sous–estimé le degréde tassement à la fin de la construction. L'analyse décrite ici, qui englobe un modéle d'état critique élastoplastique appliqué à la tension efficace, a simulé les effets du tassement de rupture et, ce faisant, a reproduit un tassement maximal proche du tassement mesuré. La sous–estimation antérieure est attribuée surtout au fait que le tassement de rupture dû au remplissage partiel du réservoir avant la fin des travaux n'a pas été analysé. L'analyse rétrospective décrite ici porte sur la période qui s'étend de la mise en chantier, en 1984, jusqu'à quatre ans environ après le premier remplissage complet, en janvier 1988. Les mouvements et tensions calculés sont comparés aux valeurs mesurées. Mise à part la bonne concordance mentionnée ci–dessus pour le tassement maximal enregistré, les valeurs de tassement mesurées tendaient à dépasser les valeurs calculées. La sous–estimation du tassement est attribuée en partie au fluage, que la modélisadon n'a pas tenté de simuler, et en partie au fait que la densité relative en place était inférieure à celle utilisée dans les essais qui avaient servi à définir les paramètres. Les distributions calcu–lées des tensions ont indiqué un transfert favorable des charges du massif au noyau, confirmant ainsi que le barrage résisterait à l'érosion interne caus&aute;e par la fracturation hydraulique. Il est toutefois possible d'estimer, à partir des relevés de tassement, dans quelle mesure le tassement était dû au fluage, et cela a été fait. Les conclusions font ressortir l'utilité de la méthodologie basée sur le tassement de rupture.

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It is acknowledged that to improve the value of the learning process and outcomes in areas such as science, technology, engineering and math, the teaching quality needs to be enhanced. Therefore, it is crucial to have access to real teaching practices. The multimodal narrative (MN) tool allows teaching practices to become public, sharable, and usable (open science perspective), preserving their holistic, complex, and ecological nature. This tool has characteristics and a structure that enable an in-depth study of teaching practices, in different contexts, with several purposes (e.g., teacher education, professional development, and research). This chapter presents MNs and the necessary steps involved in collecting multimodal data, structuring the narrative, and validating the document. MNs can be used by teachers and researchers, or other professionals, with multiple specific objectives, globally contributing to improving professional practices.

While several researchers have suggested that evolution should be explored from the initial years of schooling, little information is available on effective resources to enhance elementary school students’ level of understanding of evolution by natural selection (LUENS). For the present study, we designed, implemented, and evaluated an educational activity planned for fourth graders (9 to 10 years old) to explore concepts and conceptual fields that were historically important for the discovery of natural selection. Observation field notes and students’ productions were used to analyze how the students explored the proposed activity. Additionally, an evaluation framework consisting of a test, the evaluation criteria, and the scoring process was applied in two fourth‐grade classes (N = 44) to estimate elementary school students’ LUENS before and after engaging in the activity. Our results show that our activity allowed students to link the key concepts, resulting in a significant increase of their understanding of natural selection. They also reveal that additional activities and minor fine‐tuning of the present activity are required to further support students’ learning about the concept of differential reproduction.

While several researchers have suggested that evolution should be explored from the initial years of schooling, little information is available on effective resources to enhance elementary school students’ level of understanding of evolution by natural selection (LUENS). For the present study, we designed, implemented and evaluated an educational activity planned for fourth graders to explore concepts and conceptual fields that were historically important for the discovery of natural selection. Observation field notes and students’ productions were used to analyse how the students explored the proposed activity. Additionally, an evaluation framework consisting of a test, the evaluation criteria and the scoring process was applied in two fourth-grade classes to estimate elementary school students’ LUENS before and after engaging in the activity. Our results suggest that our activity allowed students to effectively link all of the key concepts in the classroom and produced a significant increase in their LUENS. These results indicate that our activity had a positive impact on students’ understanding of natural selection. They also reveal that additional activities and minor fine-tuning of the present activity are required to further support students’ learning about the concept of differential reproduction. We also observed a low level of teleological predictions for both pre- and post-tests.

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