Sistemas de fundação e de ancoragem em sedimentos moles
XVII Lição Manuel Rocha, 2001
DOI:
https://doi.org/10.14195/2184-8394_94_1Resumo
Os sistemas de fundação e de ancoragem de estruturas "offshore" estão a ser utilizados cada vez mais em águas profundas, onde os sedimentos do fundo do mar são predominantemente constituídos por solos moles ligeiramente sobre consolidados. Os desafios colocados pela minimização dos elevados custos de instalações "offshore", sem comprometimento da sua fiabilidade, levaram a inovações significativas nos tipos de fundação e nos métodos de instalação, com o consequente enfoque na adopção de novos e melhorados modelos analíticos. Como exemplos, referem-se as fundações " tipo saia", onde a sucção ou subpressão é utilizada para a penetração até à profundidade requerida, os novos sistemas de amarração "tipo âncora", de elevada capacidade, e os caixões por sucção. Nesta licção são apresentados os métodos de análise e de dimensionamento para um conjunto de sistemas de fundação em sedimentos moles no fundo do mar, incluindo fundações com saias, caixões colocados por sucção e amarrações "tipo âncora". São descritos métodos analíticos simplificados, comparando-se os seus resultados com os da modelação tisica e numérica.
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