SUMMARYMinarets are very slender structures with an old existence. The historical ones are made of cut-stone-block masonry assembled in peripheral cylindrical wall with an interior helicoidal stair supported on a central core and on the wall. They are spread throughout the Islamic world and constitute an important heritage not only of religious value, but also of great cultural interest. Throughout the times, these structures as part of a mosque, have suffered significant damage during the earthquakes. Istanbul presents interesting characteristics to evaluate their dynamic behavior, as they are in great number, in an area where a large event in the next 30 years has been predicted.In this paper, we performed a series of in situ ambient vibration tests to old minarets of various sizes and compared results of frequencies with numerical modeling of the same structures. For the low-amplitude motion, the frequency values of the first modes can be obtained from an empirical formulae function of the inertia of the cross-section and of the height of the main 'body.' Damping ratios for these amplitudes are of the order of 0.5-1.0%.Dynamic linear analyses of these structures indicate that for most cases very high stresses develop for PGA above 0.5 g, an input with a reasonable chance of occurring in the next 30 years. These high stresses are expected to cause the toppling of the minarets in the form that has been observed in the recent past events.

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A investigação tende a descrever o pai como parceiro de jogo que favorece a liberdade de ação; enquanto a mãe, tende a reforçar a comunicação nas interações, envolvendo afetivamente a criança. Nos casos em que a mãe brinca e o pai presta cuidados básicos à criança, a qualidade da interação pai-filhos aumenta consideravelmente. Neste estudo, observamos pai e mãe independentemente na mesma situação experimental como parceiros da criança numa atividade lúdica de construção. Comparamos os seus comportamentos quando colocados no mesmo papel. Para o efeito, foi pedido a 19 díades mãe-filho(a) e 17 díades pai-filho(a) que realizassem, em 20 minutos, um produto à sua escolha com os materiais e ferramentas disponibilizados. As crianças tinham entre 3 e 5 anos, sem atrasos de desenvolvimento identificados. Pretendemos descrever e comparar os pais (mães e pais considerados em conjunto) quanto: (i) à empatia, atenção, reciprocidade, cooperação, elaboração/fantasia e desafio proposto; (ii) à qualidade da comunicação; e (iii) aos produtos realizados e escolhas de materiais. Os nossos resultados indicam poucas diferenças entre pais e mães. Em termos de comunicação, as mães realizam mais perguntas de processo do que os pais. As diferenças mais relevantes correspondem à forma como os pais e as mães reagem com os meninos e as meninas, dando maior liberdade de ação às meninas, mais feedback positivo e revelando-se mais sensíveis a responder às suas emoções. Os meninos perderam mais interesse durante a atividade e revelaram mais sinais de aborrecimento do que as meninas. O sexo das crianças afetou mais os resultados do que o dos pais, ou seja, os pais interagiram e comunicaram distintamente com meninas e meninos. Adicionalmente, a escolaridade dos pais correlacionou-se com comportamentos mais atentos, pacientes e cooperativos dos pais. Relativamente à idade dos progenitores, os pais mais novos e com mais filhos usaram mais materiais e ferramentas.

In the recent years, many technologies of seismic protection have been developed in an attempt to mitigate the effects of earthquakes on buildings or other structures. The most important examples of seismic protection technology are the base isolation and the use of energy dissipators. A great majority of applications of this type of seismic protection had been done in new structures, and there are already a significant number of examples of the use of these technologies in seismic rehabilitation all over the world.In this paper, the analyses of the different types of seismic passive protection and their possibilities of use in structural rehabilitation is presented. The rehabilitation of structures from the old masonry historic buildings to more recent reinforced concrete buildings is discussed.Two studies of seismic rehabilitation with passive protection are presented. The first study is the rehabilitation of an old masonry lighthouse (‘Farol dos Capelinhos’, Azores) using base isolation. This structure had been affected by an earthquake and volcano eruption and needed to be reinforced. One of the studied solutions was the use of seismic base isolation at the base of the Lighthouse tower. This study and its results are presented in the paper.The second study is the rehabilitation of an old masonry building with the use of viscous dampers. This building is an example of an important part of the existing building stock of Lisbon, commonly designated by ‘Gaioleiros’. This type of buildings were constructed in the period between the end of the 19th century and the start of the 20th century, and are composed of exterior masonry walls with wood infill panels and wooden floors. This kind of structures are particularly vulnerable to the seismic action and are objects of different studies for possible retrofit interventions.

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