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In the last years some laboratory testing has been used to predict the permanent deformation behavior of bituminous mixtures. The tests methods used in Portugal include the Wheel Tracking test, the Cyclic Compression Test (Uniaxial and Triaxial) and the Repetitive Shear at Constant Height (RSCH) test. There are also the new European standards for those tests methods, with the exception of the RSCH which is essentially used in the USA. Some of testing conditions are not well defined. Therefore, it is important to study the reliability and accuracy of each test in the task of predicting permanent deformation behaviour. In this work these test methods were used in the evaluation of a commonly used mixture in Portugal. Results show that all tests are suitable for predicting permanent deformation behaviour. Thus simpler and cheaper tests are the more interesting to use.

Television White Spaces (TVWS) are a spectral opportunity, for secondary users of the spectrum to deliver broadband access to rural areas. Most of the approaches now under test worldwide use a geo-location database to inform secondary users of the available channels, and avoid interference with primary users of the spectrum. The secondary network should follow a approach capable to communicate with a geo-location spectrum database, to store and retrieve information on spectrum occupancy, location of DVB-T broadcast towers and wireless microphones, maximum EIRP of secondary White Space devices (WSDs), sensing activity and other technical parameters. One group from the Internet Engineering Task Force (IETF) is presently working on the definition of a protocol to access white spaces databases – PAWS. The IETF draft protocol was chosen and considered flexible enough to be adapted for the CREW-TV project model and requirements, since it is more comprehensive and less specific on details than other proposals.

A deformação permanente em misturas betuminosas é uma degradação de pavimentos rodoviários frequente mas para a qual ainda não existe uma metodologia que possa de forma cabal prever a sua evolução, nomeadamente para as camadas betuminosas. Para avaliar a susceptibilidade destas à deformação permanente existem vários ensaios laboratoriais, como sejam, o ensaio de Wheel Tracking e o de Fluência Dinâmica. Neste trabalho faz-se a comparação dos resultados obtidos para uma mistura betuminosa comum em Portugal com os ensaios laboratoriais de Wheel Tracking e de Fluência Dinâmica realizados, respectivamente, de acordo com a prEN 12697-22 e a prEN 12697-25. Foram ensaiados provetes produzidos em laboratório e recolhidos em obra. Os resultados obtidos confirmam a aplicabilidade dos ensaios e ainda que o parâmetro velocidade de deformação pode ser utilizado na caracterização do comportamento de misturas betuminosas à deformação permanente.