This paper reports the first attempt of developing macro-scale auxetic structures based on re-ent... more This paper reports the first attempt of developing macro-scale auxetic structures based on re-entrant hexagon design from braided composite materials for civil engineering applications. Braided composite rods (BCRs) were produced and arranged as longitudinal and horizontal elements to produce three types of auxetic structures: (1) basic re-entrant hexagon structure, (2) basic structure modified by adding straight longitudinal elements and (3): structure-2 modified by changing structural angle. The influence of various material and structural parameters as well as structure type on Poisson's ratio and tensile properties was thoroughly investigated. The auxetic behaviour was found to strongly depend on the structural angle and straight elements, resulting in lower auxeticity with lower angles and in presence of straight elements. Material parameters influenced the auxetic behaviour to a lesser extent and a decrease in auxetic behaviour was noticed with increase in core fibre linear density and using stiffer fibres such as carbon. The reverse effect was observed in case of tensile strength and work of rupture. Among these structures, structure-3 exhibited good auxetic behaviour, balanced tensile properties, and high energy absorption capacity and their auxetic behaviour could be well predicted with the developed analytical model. Therefore, these novel structures present good potential for strengthening of civil structures.
Design of reinforced concrete structures can be described by the following consecutive steps: 1. ... more Design of reinforced concrete structures can be described by the following consecutive steps: 1. Select the initial dimensions of all the structural elements using simple rules of thumb or experience. These dimensions should be able to satisfy the serviceability and ultimate limit states, and should fulfill the requirements for adequate site execution and any other applicable requirement (e.g. acoustic isolation, fire protection, etc.). 2. Perform a global structural analysis to calculate the internal forces (or stresses) due to the combination of loads defined in the codes. The method almost used exclusively today is the finite element method and the behaviour of the structure is assumed to be linear elastic at this stage.
A Igreja Arminiana (ou Igreja de Santa Maria) está localizada a Noroeste da área fortificada da c... more A Igreja Arminiana (ou Igreja de Santa Maria) está localizada a Noroeste da área fortificada da cidade de Famagusta, em frente à Igreja das Carmelitas. É um edifício de aspeto militar construído em 1346 por refugiados arménios originários da Cilícia e acredita-se que era parte integrante de um conjunto monástico, cultural e teológico importante, onde São Nerses de Lambron disse ter estudado, e cujas fundações sobreviveram até meados do século XX. A Igreja que ainda permanece de pé não tem sido utilizada desde 1571, foi utilizada de forma intermitente desde a segunda metade do século XX, ocupada desde 1974 pelo exército turco e inacessível, pois está localizada numa “área militar", até finais de 2005. Desde então, uma série de pesquisas têm sido direcionadas para a compreensão e preservação deste monumento, bem como a área circundante. Esta comunicação apresenta os resultados do levantamento com georadar realizado em torno da Igreja Arminiana afim de mapear as fundações do antig...
This paper reports the first attempt of developing macro-scale auxetic structures based on re-ent... more This paper reports the first attempt of developing macro-scale auxetic structures based on re-entrant hexagon design from braided composite materials for civil engineering applications. Braided composite rods (BCRs) were produced and arranged as longitudinal and horizontal elements to produce three types of auxetic structures: (1) basic re-entrant hexagon structure, (2) basic structure modified by adding straight longitudinal elements and (3): structure-2 modified by changing structural angle. The influence of various material and structural parameters as well as structure type on Poisson's ratio and tensile properties was thoroughly investigated. The auxetic behaviour was found to strongly depend on the structural angle and straight elements, resulting in lower auxeticity with lower angles and in presence of straight elements. Material parameters influenced the auxetic behaviour to a lesser extent and a decrease in auxetic behaviour was noticed with increase in core fibre linear density and using stiffer fibres such as carbon. The reverse effect was observed in case of tensile strength and work of rupture. Among these structures, structure-3 exhibited good auxetic behaviour, balanced tensile properties, and high energy absorption capacity and their auxetic behaviour could be well predicted with the developed analytical model. Therefore, these novel structures present good potential for strengthening of civil structures.
Design of reinforced concrete structures can be described by the following consecutive steps: 1. ... more Design of reinforced concrete structures can be described by the following consecutive steps: 1. Select the initial dimensions of all the structural elements using simple rules of thumb or experience. These dimensions should be able to satisfy the serviceability and ultimate limit states, and should fulfill the requirements for adequate site execution and any other applicable requirement (e.g. acoustic isolation, fire protection, etc.). 2. Perform a global structural analysis to calculate the internal forces (or stresses) due to the combination of loads defined in the codes. The method almost used exclusively today is the finite element method and the behaviour of the structure is assumed to be linear elastic at this stage.
A Igreja Arminiana (ou Igreja de Santa Maria) está localizada a Noroeste da área fortificada da c... more A Igreja Arminiana (ou Igreja de Santa Maria) está localizada a Noroeste da área fortificada da cidade de Famagusta, em frente à Igreja das Carmelitas. É um edifício de aspeto militar construído em 1346 por refugiados arménios originários da Cilícia e acredita-se que era parte integrante de um conjunto monástico, cultural e teológico importante, onde São Nerses de Lambron disse ter estudado, e cujas fundações sobreviveram até meados do século XX. A Igreja que ainda permanece de pé não tem sido utilizada desde 1571, foi utilizada de forma intermitente desde a segunda metade do século XX, ocupada desde 1974 pelo exército turco e inacessível, pois está localizada numa “área militar", até finais de 2005. Desde então, uma série de pesquisas têm sido direcionadas para a compreensão e preservação deste monumento, bem como a área circundante. Esta comunicação apresenta os resultados do levantamento com georadar realizado em torno da Igreja Arminiana afim de mapear as fundações do antig...
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