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Fiber reinforced polymers (FRP) are often used to strengthen RC structures.
Despite intense research, durability of reinforced concrete (RC) retrofitted with FRP remains insufficiently known. Long time behavior of the bond laminate-concrete, in flexural strengthening, under environmental action is not well known, conditioning Codes and engineers. An experimental program that subjected RC beams, externally reinforced with Glass FRP (GFRP) strips, to temperature and salt water cycles, for up to 10000h is reported.
At selected intermediate times, the RC beams were loaded to failure in bending. Rupture took place, normally, by tensile failure of concrete at a short distance from the interface with GFRP. The results showed that freeze-thaw cycles were the most severe of the environmental
conditions. The study also generated also non-linear bond-slip relationships from the experimental data. Numerical modeling has been undertaken, based on a commercial code.
The model is based on smeared cracking. Parameters needed for the characterization, namely cohesion and friction angle, were obtained from shear tests conceived for the effect.

Analisa-se e caracteriza-se por via experimental a ligação entre elementos de betão armado e materiais compósitos, nomeadamente com base nas fibras de vidro. Fabricaram-se vigas de betão armado que foram exteriormente reforçadas com GFRP. Os resultados obtidos experimentalmente foram comparados com os resultados conseguidos por intermédio de modelação computacional, recorrendo-se ao programa de cálculo ATENA 2D. Para melhor modelação de elementos de interface, foram realizados ensaios de corte tendo-se obtido valores que permitiram caracterizar a lei de rotura de Mohr-Coulomb. Os parâmetros estudados foram a evolução das forças máximas absorvidas pelo reforço; as tensões de aderência máximas; a distribuição das tensões de aderência.

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Four different localities from the Late Jurassic of Lourinhã formation with eggshells and embryos were studied: Paimogo (lower Amoreira-Porto Novo member), Peralta (Praia Azul member), Porto das barcas (Bombarral member) and Casal da Rôla (Amoreira-Porto Novo member). All but Casal da Rôla have embryonic material. Preliminary results show that eggshells from Paimogo correspond to obliquiprismatic morphotype (0.92mm thick), similar to those from Morrison Formation. Within Paimogo site a different type of eggshell was discovered, having a radial section of 153 μm with a mammilary layer measuring 65 μm. Porto das Barcas eggshells represent a discretispherulitic morphotype (1,23 mm thick).
This locality presents a nest 60-cm diameter containing many eggshells but an indeterminate number of eggs. Some embryonic bones were discovered between the eggshells including teeth and skull bones showing that the eggs belong to a saurischian, tentatively a sauropod dinosaur. Peralta nest eggshells are preliminary ascribed to obliquiprismatic morphotype (column: 0,56mm and mammilla: 0,21mm) probably related to Paimogo’s nest taxon (Lourinhanosaurus). Peralta site bears embryonic bones namely small theropod teeth associated with bone fragments, and unidentifiable dinosaur vertebra. Only eggshells have been collected at Casal da Rôla (ML1194). The eggshells (0,78mm thick) are prismatic morphotype and it was impossible to determine the pore system, the outer surface is smooth with no ornamentation.
Lourinhã formation has the oldest sauropod and theropod nest with embryos known so far.

Spreadsheets can be viewed as a highly flexible end-users programming environment which enjoys wide-spread adoption. But spreadsheets lack many of the structured programming concepts of regular programming paradigms. In particular, the lack of data structures in spreadsheets may lead spreadsheet users to cause redundancy, loss, or corruption of data during edit actions. In this paper, we demonstrate how implicit structural properties of spreadsheet data can be exploited to offer edit assistance to spreadsheet users. Our approach is based on the discovery of functional dependencies among data items which allow automatic reconstruction of a relational database schema. From this schema, new formulas and visual objects are embedded into the spreadsheet to offer features for auto-completion, guarded deletion, and controlled insertion. Schema discovery and spreadsheet enhancement are carried out automatically in the background and do not disturb normal user experience.

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This paper presents techniques and tools to transform spreadsheets into relational databases and back. A set of data refinement rules is introduced to map a tabular datatype into a relational database schema. Having expressed the transformation of the two data models as data refinements, we obtain for free the functions that migrate the data. We use well-known relational database techniques to optimize and query the data. Because data refinements define bidirectional transformations we can map such database back to an optimized spreadsheet. We have implemented the data refinement rules and we have constructed tools to manipulate, optimize and refactor Excel-like spreadsheets.