1,720,974 research outputs found
Sustainable Strengthening Techniques for Masonry Structures
No full textReducing the energy consumption is an important objective of the construction industry and this also applies for renovation, retrofit and refurbishment of existing buildings. Masonry buildings often need to be retrofitted and the use of Fibre Reinforced Polymeric (FRP) materials has proven to be a viable solution. With the inevitable declining of fossil fuels, carbon fibres and epoxy resins must be substituted with greener materials. This paper reports the results of several experimental investigations recently conducted by the authors using glass fibre meshes embedded into an inorganic matrix (known as FRCM: Fibre Reinforced Cementitious Matrix) to reinforce historic masonry constructions. This strengthening technique has been applied in laboratory to reinforce masonry wall panels, tile brickwork vaults and to construct masonry ring-beams at eaves level of existing buildings. The mechanical behaviour of the reinforced masonry elements have been significantly enhanced and test results demonstrate that is possible to avoid the use of more traditional composite reinforcements like high-strength carbon fibres and epoxy resins to bond the reinforcing materials to the masonry substrate
BEHAVIOUR OF SMALL MASONRY ASSEMBLAGES REINFORCED WITH A STEEL CORD REINFORCED JOINT REPOINTING
No full textUnreinforced masonry (URM) walls are one of the oldest and most common types of construction elements in the world. However they are susceptible to failure when exposed to overstresses, caused by out-of-plane and in-plane loads. In this paper a new method for reinforcing brickwork masonry using steel cords embedded into the mortar joints is proposed. The average cord diameter of 3 mm, enables reinforcement to be retrofitted to brick and irregular stone-masonry walls. Joints can then be repointed to hide the cords, so that no evidence of strengthening work is visible on the final finished façade. The bending behaviour of 24 brick-masonry small assemblages has been evaluated. Specimens have been prepared using two courses of bricks with nominal dimensions of 215 x 102 x 65 mm and two different types of lime-based mortar. After the mechanical characterization of the materials used for construction and reinforcement, an experimental was carried out to assess the potential of the technique comparing the results of bending test achieved for unreinforced specimens. Test results show an increase of bending capacity and of flexural stiffness up to 49.8 and 475%, respectively
STRUCTURAL ANALYSIS OF TRANSVERSAL STEEL CONNECTORS APPLIED ON MULTI-LEAF WALLS
No full textOver the last fifteen years, new techniques and materials have been used to retrofit masonry structures for improved seismic performance as well as a variety of other strengthening applications. The global behavior of a stone masonry wall is often governed by the level of connection between masonry leaves and the overall quality of the masonry material (mortar, block and arrangement). This paper presents the results of an investigation carried out on multi-leaf stone masonry panels retrofitted using stainless steel rod inserted in a grouted fabric sleeve. The paper also reports the results of a non-linear numerical investigation calibrated using laboratory tests. Several wall panels were assembled in the laboratory using solid calcareous stones and weak mortar and the effectiveness of the connectors was tested in shear and compression on both virgin and damaged wall panels. Experimental results show that a substantial improvement of the panels’ mechanical behavior can be achieved by applying transverse connectors. The feasibility of using the 3-Dimensional (3D) finite element model to analyze multi-leaf walls reinforced with transverse connectors is examined by comparing the model to experimental data
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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