A geometrical non-linear model for cable systems analysis

Cable structures are commonly studied with simplified analytical equations. The evaluation of the accuracy of these equations, in terms of equilibrium geometry configuration and stress distribution was performed for standard cables examples. A three-dimensional finite element analysis (hereafter FEA) procedure based on geometry-dependent stiffness coefficients was developed. The FEA follows a classical procedure in finite element programs, which uses an iterative algorithm, in terms of displacements. The theory is based on a total Lagrange formulation using Green-Lagrange strain. Pure Newton-Raphson procedure was employed to solve the non-linear equations. The results show that the rigid character of the catenary’s analytical equation, introduce errors when compared with the FEA

On the Evaluation of the Mechanical Behaviour of Structural Glass Elements

Glass can be considered to be a high-technology engineering material with a multifunctional potential for structural applications. However, the conventional approach to the use of glass is often based only on its properties of transparency and isolation. It is thus highly appropriate and necessary to study the mechanical behaviour of this material and to develop adequate methods and models leading to its characterisation. It is evident that the great potential of growth for structural glass applications is an important opportunity of development for the glass industry and the building/construction sectors. The work presented in this paper is a reflection of this conclusion. The authors shortly present the state-of-the-art on the application of glass as a structural element in building and construction, and refer to other potential fields of application and available glass materials. The experimental procedures and methods adopted in three-point bending tests performed on 500 × 100 [mm2] float, laminated and tempered glass specimens with thicknesses between 4 and 19 mm are thoroughly described. The authors evaluated the mechanical strength and stiffness of glass for structural applications. This work contributes to a deeper knowledge of the properties of this material

Estimation of losses for adobe buildings in Pakistan

Adobe buildings are vulnerable to seismic forces. Large scale destructions and casualties have been caused due to the collapse of adobe buildings during the past earthquakes. A significant number of adobe structures exist in different parts of Pakistan, similar to other parts of the world. Since Pakistan lies in a seismic active region, it is necessary to assess the level of vulnerability of these buildings in order to estimate associated losses during a seismic event. This paper presents the results of a study which was conducted to quantify damages to adobe buildings based on their fragility curves. The adobe buildings were found to be highly vulnerable to low intensity earthquakes. The vulnerability of these buildings has been compared with the European adobe buildings. It was noted that Pakistani adobe buildings were slightly less resistant to earthquakes as compared to similar buildings in Europe. Retrofitting solutions were suggested in order to increase the seismic capacity of adobe buildings in Pakistan

Análise de um quarteirão da Avenida Dr. Lourenço Peixinho - Aveiro

A Avenida Dr. Lourenço Peixinho, construída no primeiro quarto do século XX, surge da necessidade de expansão da cidade de Aveiro, tendo sido determinante para o desenvolvimento desta, estabelecendo a ligação entre a estação de caminho-de-ferro e o centro da cidade. Esta veio alterar o parque edificado até aquela data nesta zona da cidade. Inicialmente houve a preocupação e cuidado em construir de uma forma planeada de forma a garantir uma coerência de linguagem arquitectónica mas, com o decorrer dos anos, este cuidado foi-se esvanecendo. Assim, actualmente as elegantes moradias tradicionais de dois andares em estilo arte nova surgem paredes-meias com prédios recentes em betão armado de três a sete andares. Na Avenida encontram-se construções que retratam uma série de épocas, desde o neoclássico, passando pela arte-nova e o modernismo. Actualmente, a maioria destas encontra-se em avançado estado de degradação, causado pela falta de manutenção e conservação e, em alguns casos, devido a alterações estruturais inadequadas em intervenções recentes. Esta situação atingiu-se devido à falta de estratégias concertadas para a conservação do património existente. Assim, justifica-se que sejam estudadas e desenvolvidas metodologias de análise e soluções de conservação, e eventualmente reforço, que, respeitando a identidade do património edificado, permitam avaliar a segurança e reduzir a vulnerabilidade sísmica destas construções existentes. Pretende-se com esta comunicação apresentar os principais resultados do trabalho de caracterização de um quarteirão da Avenida Dr. Lourenço Peixinho, nomeadamente no que respeita à sua época de construção, material da estrutura resistente, regulamentação usada, estado de conservação, descontinuidades observadas, intervenções estruturais realizadas, cálculo sísmico, etc

Assessment of seismic performance of adobe structures in Pakistan and Portugal

Adobe buildings exist in different parts of the world. The construction of these buildings can be carried out economically, using locally available materials and skills that do not require use of modern machinery. Therefore, adobe buildings provide an economic housing option. The construction of adobe structures is carried out based on traditional construction practices which vary from region to region. This paper presents the results of a study which was conducted to study the construction practices of adobe buildings in Pakistan and Portugal in the context of their seismic vulnerability. The adobe buildings in both these countries were found to be subjected to seismic hazard levels which, although is low in some regions, may cause significant damages. Lack of essential elements or details for the adequate seismic performance was found in the adobe buildings in both regions

Análise da resistência mecânica e da absorção de blocos de terra comprimida feitos com cinza do bagaço da cana-de-açúcar

O cultivo da cana-de-açúcar e a produção de seus derivados está intimamente ligado à própria história e ao desenvolvimento do Brasil. A destinação das cinzas do bagaço da cana-de-açúcar (CBC) é um dos problemas enfrentados pelos administradores das usinas, uma vez que essas cinzas constituem-se em resíduos finais do processo industrial, no qual não há possibilidade de redução do mesmo. O bloco de terra comprimida (BTC) é uma alternativa aos tijolos queimados de barro, tendo como vantagem de não necessitar de altas temperaturas de cura. Dessa forma, considerando a importância da inclusão de resíduos nos materiais de construção e priorizando as técnicas construtivas com terra, o objetivo deste trabalho foi analisar a influência da adição das cinzas em BTCs por meio de ensaios de resistência à compressão e de absorção. Para as análises, os blocos foram produzidos em duas séries, uma com 6% e outra com 12% de cimento em adição a mistura de solo. O solo utilizado foi proveniente da região de Aveiro, Portugal, e para a correção do teor de finos, utilizou-se o caulino. Para cada série de blocos, utilizou-se teores de adição de CBC nos valores de 0%, 2%, 4% e 8%. Os resultados obtidos permitiram concluir que a CBC pode ser incorporado aos blocos produzidos com terra crua sem alterar suas características mecânicas

Seismic vulnerability of churches in Faial and Pico islands, Azores

Earthquakes represent one of the main cause of serious damage and loss of historic and architectural heritage. Interventions to preserve these building should start with a careful knowledge and assessment of their seismic vulnerability, in order to support any needed retrofitting and strengthening measures. This paper proposes a procedure to register and diagnose of the level of damage on churches after the occurrence of an earthquake, and also to assess the seismic vulnerability of this type of construction. This procedure was applied to sixteen churches in the Azores islands which were hit by the July 9th 1998 earthquake. Belfries of church towers are elements with a particular seismic vulnerability. For this reason, and based on the Italian methodology proposed by the Linee Guida (2006), it is applied to belfries of two churches from Pico (Azores), a simplified mechanical model for assessment of seismic vulnerability of this type of structures

A mechanical method for the vulnerability assessment of masonry buildings

This paper discusses a mechanical model for the vulnerability assessment of masonry buildings that takes into account the uncertainties inherent to the structural parameters and the limit states. At first a bilinear model for the capacity spectrum for masonry buildings is derived as an analytical function of a few number of geometrical and mechanical parameters. Applying a suitable procedure for the uncertainty propagation, the statistical moments of the structural capacity is obtained as a function of the statistical moments of the input parameters, showing the role of each in the results. Using the capacity spectrum method formulated in the so called N2 procedure, vulnerability analysis is carried out with respect to a certain number of random limit states which depend, in turn, on the building parameters. Fragility curves are derived taking into account the uncertainties of each quantity involved

Typological characterization of the Portuguese traditional schist constructions

Schist constructions represent an important cultural, architectural and historical legacy in Europe, and particularly in Portugal, that urges to preserve. Included among the traditional Portuguese architectural heritage, there are many traditional buildings in schist masonry, distributed from North to South, varying the types of buildings, the constructive methodologies and even the material schist, which may vary in properties and characteristics, depending on the region where it is extracted. Over the years, this traditional architecture has implemented a sustainable construction through the use of natural materials available in the region, as today it is desired to implement in the contemporary construction practice. The constructive techniques and solutions of these traditional structures have been developed in direct relation with various factors as economic, environmental and social, adapting to different requirements over the time, originating a wide diversity of construction typologies that today exist in Portugal. The present study intends to describe and characterize the different building typologies of the traditional schist construction in Portugal mainland. Examples of more prominent constructions, considering its dimensions and/or patrimonial importance are presented and analyzed

Measurement and determinants of health poverty and health richness: evidence from Portugal

The analysis of health inequalities is a critical topic for health policy. With data for Portugal, we propose an algorithm to convert information provided by the official National Health Survey to EuroQol. Based on these data, we make two contributions. First, we extend measures and methods commonly applied in other fields of economic research in order to quantify the phenomena of health poverty, richness, and inequality. Second, using an ordered probit model, we evaluate the determinants of health inequalities in Portugal. The results show that there is a remarkable level of health inequality, with significant rates of poverty (11.64 %) and richness (22.64 %). The econometric study reveals that gender, age, education, region of residence, and eating habits are among the most critical determinant factors of health.info:eu-repo/semantics/acceptedVersio