Artigos de Revista

O Forte de Nossa Senhora da Graça localiza-se no Monte de Nossa Senhora da Graça, a norte da cidade de Elvas. É construído no final do século XVIII a mando de D. José I, classificado como Património Nacional em 1910 e como Património Mundial, pela UNESCO, em 2012. Na construção do forte utilizaram-se pedras e terras sobrantes das minas abertas no maciço rochoso do monte, assim como outros materiais existentes nas proximidades do local da construção, tal como areia e material cerâmico. No âmbito da sua nomeação pela UNESCO, em 2012, em conjunto com as restantes fortificações de Elvas, como Património Mundial, foi implementado um plano de conservação e restauro do Forte que envolve, entre outras atividades, uma caracterização detalhada dos materiais empregues na sua construção.

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The railway track at transition zones to bridges or to other structures usually requires considerably more interventions tomaintain the same open track service quality and safety levels. Under sleeper pads (USP) have been reported to contribute toreduce degradation and frequency of maintenance operations in open ballasted tracks, and recent numerical studies havesuggested its use in transition zones. In this study, the in

The value of on-line UV/vis spectroscopy for wastewater quality monitoring in two different sewage management situations was confirmed. For decentralised wastewater treatment, spectral on-line monitoring of key quality parameters (COD, organic N) at the WWTP inlet was found to be possible, at two plants of different sizes and inflow characteristics. The produced data allowed the dynamic modelling of the treatment processes and the testing of control scenarios. In situ spectral monitoring in sewers was also successfully tested, with high potential in the management of drainage networks subjected to storm water inflows. In both situations, on-line UV/ vis spectrophotometry can thus become a key technology for real-time system management, leading to better use of infrastructures and resources and the achievement of environmental objectives more consistently and at lower costs.

One of the main motivations for hierarchical modeling is to understand how properties, composition and structure at lower scale levels may influence and be used to predict the material properties at macroscopic and structural engineering scales. Structural timber is, in most cases, characterized by three parameters usually designated as reference properties: density, bending modulus of elasticity and bending strength.The present paper addresses a review on different possibilities for obtaining reliable data about the mechanical behavior of timber elements by collecting information at different levels and by organizing that information into a hierarchy of sequential levels (from lowest to highest). The applicability and limitations of statistic and probabilistic methods on the prediction and inference of timber

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This article describes the implementation of a monitoring system on the breakwater at the Funchal Port (Madeira Island, Portugal) for the purpose of understanding its dynamic behavior and the temporal evolution of structural health. The monitoring system focuses on the breakwater superstructure and aims to identify the evolution of damage on the breakwater and analyze the impact of cruise ships docking and undocking. The system includes the measurement of displacements through geodetic techniques using global navigation satellite systems and the measurement of vibrations using accelerometers. Ten observation campaigns were performed over almost 3 years. As the measured displacements during this period were less than 7.5 mm it can be concluded that, despite some visible cracks, the breakwater superstructure did not suffer significant structural changes. It was shown from the measured acceleration records that some of the main modal parameters could be identified, namely the main natural frequencies of the superstructure. Through an analysis of the natural frequencies progression over time, it will be possible to identify deterioration effects on the foundation and/or the superstructure. The comparison of natural frequencies identified could be useful to evaluate the impact of these events on structural health.

This research was focused on the use of the modified Chapelle test as a direct laboratory methodology to access the pozzolanic activity of both experimental and commercial metakaolins. At the same time, this test was used in the evaluation of experimental metakaolins. This chemical test, performed during 16 hours at 90 °C, allows the quantification of portlandite fixed by the metakaolin sample. The calcium hydroxide that was not consumed is quantified by acid titration (HCl), and the test result is expressed in mg of fixed calcium hydroxide by g of metakaolin. According to this test, the pozzolanic activity of a metakaolin should not be less than 700 mg Ca(OH)2 / g metakaolin. The modified Chapelle pozzolanic activity of six commercial metakaolins was evaluated between 920 and 1560 mg Ca(OH)2 / g metakaolin. From the seven experimental metakaolins produced between 750 ºC and 940 ºC, a material with modified Chapelle pozzolanic activity value of 1240 mg Ca(OH)2 / g metakaolin was obtained, which is similar to some tested commercial metakaolins produced at industrial scale. The metakaolin produced at 800 ºC was ground, resulting in a particle size reduction of ? 4x less and a consequent increase of 21 % in the pozzolanic activity.

Methods and devices for in situ establishment of mechanical properties of wood have been recently developed in cooperation with European, US and Japanese researchers. The development of these new methods was motivated by requirements from engineers who need highly accurate data of mechanical properties of specific elements to plan renovations of historic buildings. Reliable data can replace overlyconservative values (usually provided by visual strength grading) in structural analysis, which allows the retention of more original material as the behavior of specific elements is safely assessed. The recently developed methods, which are described in this chapter, are tensile strength of small samples, tensile Young