Seismic vulnerability assessment of the old city centre of Seixal, Portugal

The seismic vulnerability assessment of old traditional masonry building stocks, in a seismic risk mitigation perspective, is truly essential not only for buildings with recognized historical and patrimonial value, but also, in relation to regular buildings. In this sense, this paper approaches the issue of the seismic vulnerability assessment of masonry buildings through the application of a simplified methodology to building stock of the old city centre of Seixal, Portugal. This methodology is based on a vulnerability index, suitable in the evaluation of damage and in the creation of large scale loss scenarios (economical and human). Over 500 buildings were evaluated in accordance with the referred methodology and the results obtained were then integrated into a Geographical Information System tool. The integration of this kind of vulnerability and loss results into a GIS tool allows that city councils or regional authorities make their decisions based on a global view of the site under analysis, which led to more accurate and faster decisions either in terms of risk mitigation strategies or rehabilitation plans. This tool can also assumes great importance in the construction of safety and rescue plans

Vulnerability assessment of urban building stock: a hierarchic approach

In the last decades the evaluation of the seismic risk are of rising concern, considered essential in the activity and definition of strategy planning and urban management. The evaluation of the seismic vulnerability of the existent building stock in the perspective of the seismic risk mitigation should not be placed only in relation to the isolated buildings of relevant historical and cultural importance, but also, in relation to the agglomerate of buildings in urban centres. The chronological construction process frequently results in characteristic heterogeneity of masonry and wall connection quality. In addition, buildings do not constitute independent units given that they share the mid-walls with adjacent buildings and the façade walls are aligned. This way, as post-seismic observations proved, buildings do not have an independent structural behaviour, but they interact amongst themselves, mainly for horizontal actions and so the structural performance should be studied at the level of the aggregate and not only for each isolated building. In most cases, for masonry structures there is no need for sophisticated dynamic analyses for seismic resistance verification or vulnerability assessment. This is even more relevant when an assessment at the level of a city centre is pursued. In this work, the results of evaluation of the vulnerability will be presented in accordance to three proposed methodologies based on a vulnerability index that consequently allows the evaluation of damage and creation of loss scenarios (economical and human) not only at the level of the building and its façade walls but also at the level of the aggregates. It will be discussed and evaluated the application of the referred methodologies and its integration in an SIG platform

Analysing the Portuguese urban system from a quality of life viewpoint

The idea of studying positive and negative features involved in city living is not new. Relevant works, as the classical “Where to live in Britain in 1988”, by Findlay et al., stressed the importance of several quality of life dimensions. In Portugal, a research team based in the Department of Civil Engineering at the University of Minho developed in 1998-2000 a study on quality of life in the major eighteen Portuguese cities. Results of the evaluation models developed for the dimensions considered were integrated in a quality of life grand index and mapped through a GIS system. This paper presents the quality of life surfaces developed for Portugal. In particular, it explores the overlay of quality of life and population density surfaces, attempting to find out the relationship between both

Metodologia de avaliação da vulnerabilidade sísmica das paredes de fachada de edifícios tradicionais de alvenaria

Nas últimas décadas, têm vindo a ser desenvolvidos vários trabalhos no domínio da avaliação da vulnerabilidade sísmica das construções tradicionais de alvenaria. No entanto, a grande maioria das metodologias de avaliação propostas e aplicadas têm-se focado no comportamento global do edifício, não dando sempre a devida atenção aos mecanismos locais, como é o caso das paredes de fachada. Neste artigo propõe-se uma metodologia simplificada para a avaliação da vulnerabilidade sísmica das paredes de fachada de edifícios tradicionais de alvenaria. Esta metodologia é aplicada às fachadas de uma vasta família de edifícios da Baixa de Coimbra. Os resultados obtidos são apresentados e analisados, tirando partido do apoio de uma ferramenta integrada em SIG. Com base em informação relativa aos danos observados em edifícios tradicionais após o sismo que abalou em Abril de 2009 a região Italiana de Abruzzo, desenvolveu-se e calibrou-se uma curva analítica para estimar o grau de dano médio para as paredes de fachada. Definida a função de vulnerabilidade para fachadas, construiu-se então uma metodologia para elaboração de cenários de dano. Para exemplificar a aplicabilidade dos resultados obtidos, elaborou-se uma proposta de caminhos de evacuação de suporte ao planeamento de uma situação de emergência pós-sismo na Baixa de Coimbra