935 resultados para Faria, Almeida, 1943-


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In-plane shear capacity formulation of reinforced masonry is commonly conceived as the sum of the capacities of three parameters, viz, the masonry, the reinforcement, and the precompression. The term “masonry” incorporates the aspect ratio of the wall without any regard to the aspect ratio of the panels inscribed (and hence confined) by the vertical and the horizontal reinforced grout cores. This paper proposes design expressions in which the aspect ratio of such panels is explicitly included. For this purpose, the grouted confining cores are regarded as a grid of confining elements within which the panels are positioned. These confined masonry panels are then considered as building blocks for multi-bay, multi-storied confined masonry shear walls and analyzed using an experimentally validated macroscopic finite-element model. Results of the analyzes of 161 confined masonry walls containing panels of height to length ratio less than 1.0 have been regressed to formulate design expressions. These expressions have been first validated using independent test data sets and then compared with the existing equations in some selected international design standards. The concept of including the unreinforced masonry panel aspect ratio as an additional term in the design expression for partially grouted/confined masonry shear walls is recommended based on the conclusions from this paper.

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The elastodynamic response of a pair of parallel rigid strips embedded in an infinite orthotropic medium due to elastic waves incident normally on the strips has been investigated. The mixed boundary value problem has been solved by the Integral Equation method. The normal stress and the vertical displacement have been derived in closed form. Numerical values of stress intensity factors at inner and outer edges of the strips and vertical displacement at points in the plane of the strips for several orthotropic materials have been calculated and plotted graphically to show the effect of material orthotropy.

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This thesis examines the ruins of the medieval Bridgettine (Birgittan) monastery of Naantali (Vallis Gratiae, f. 1443) in Finland and the transformation of the site into a national heritage and a memory landscape. It was archaeologically surveyed in the 19th century by Professor Sven Gabriel Elmgren (1817 1897). His work was followed by Dr. Reinhold Hausen (1850 1942), who excavated the site in the 1870s. During this time the memories of Saint Bridget (Birgitta) in Sweden were also invented as heritage. Hausen published his results in 1922 thus forming the connection with the next generation of actors involved with the Naantali site: the magnate Amos Anderson (1878 1961), the teacher Julius Finnberg (1877 1955) and the archaeologist Juhani Rinne (1872 1950). They erected commemorative monuments etc. on the Naantali site, thus creating a memory landscape there. For them, the site represented the good homeland in connection with a western-oriented view of the history of Finland. The network of actors was connected to the Swedish researchers and so-called Birgitta Friends, such as state antiquarian Sigurd Curman (1879 1966), but also to the members of the Societas Sanctae Birgittae and the Society for the Embellishment of Pirita, among others. Historical jubilees as manifestations of the use of history were also arranged in Naantali in 1943, 1993 and 2003. It seems as if Naantali is needed in Finnish history from time to time after a period of crisis, i.e. after the Crimean War in the 1850s, the civil war of 1918, during World War II and also after the economic crisis of the early 1990s. In 2003, there was a stronger focus on the international Saint Bridget Jubilee in Sweden and all over Europe. Methodologically, the thesis belongs to the history of ideas, but also to research on the use of history, invented traditions and lieux de mémoire. The material for the work consists of public articles and scholarly texts in books or newspapers and letters produced by the actors and kept in archives in Finland, Sweden and Estonia, in addition to pictures and erected commemorative monuments in situ in the Western Finnish region. Keywords: Nådendal, Naantali monastery, Bridgettines, St. Bridget, use of history, lieux de mémoire, invented traditions, commemorative anatomy, memory landscape, Saint Bridget jubilees , S. G. Elmgren, R. Hausen, A. Anderson, J. Finnberg, J. Rinne, S. Curman, High Church Movement, Pirita, Vadstena.

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A modified conventional direct shear device was used to measure unsaturated shear strength of two silty soils at low suction values (0 ~ 50 kPa) that were achieved by following drying and wetting paths of soil water characteristic curves (SWCCs). The results revealed that the internal friction angle of the soils was not significantly affected by either the suction or the drying wetting SWCCs. The apparent cohesion of soil increased with a decreasing rate as suction increased. Shear stress-shear displacement curves obtained from soil specimens subjected to the same net normal stress and different suction values showed a higher initial stiffness and a greater peak stress as suction increased. A soil in wetting exhibited slightly higher peak shear stress and more contractive volume change behavior than that of soil in drying at the same net normal stress and suction.

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Replacement of deteriorated water pipes is a capital-intensive activity for utility companies. Replacement planning aims to minimize total costs while maintaining a satisfactory level of service and is usually conducted for individual pipes. Scheduling replacement in groups is seen to be a better method and has the potential to provide benefits such as the reduction of maintenance costs and service interruptions. However, developing group replacement schedules is a complex task and often beyond the ability of a human expert, especially when multiple or conflicting objectives need to be catered for, such as minimization of total costs and service interruptions. This paper describes the development of a novel replacement decision optimization model for group scheduling (RDOM-GS), which enables multiple group-scheduling criteria by integrating new cost functions, a service interruption model, and optimization algorithms into a unified procedure. An industry case study demonstrates that RDOM-GS can improve replacement planning significantly and reduce costs and service interruptions.