1,721,047 research outputs found
INFLUENCE OF BOLT DIAMETER ON THE BEARING FAILURE LOAD OF GFRP BOLTED LAMINATES
Get PDFMany theoretical as well as experimental studies have been recently carried out by researchers working in the field of civil engineering on the design and verification problem of structural bolted joints for structures realized with Fibre Reinforced Polymers (FRP). It worth taking into account the results obtained by Camanho and Matthews [2], Ekh, Schön and Melin [3, 4], Hassan, Mohamedien and Rizkalla [5], Ireman [6], Kelly and Hallström [7], Li, Kelly and Crosky [8], Lie, Yu and Zhao [9], Starikov and Schön [10], Vangrimde and Boukhili [11, 12], Xiao and Ishikawa [13], Yan, Wen, Chang and Shyprykevich [14].
The results of these studies have highlighted the influence on typical failure modes of FRP bolted joints of some main factors as being: 1) stacking sequence of the laminates; 2) joint geometry: bolt diameter, plate width, end distance and thickness of the composite member; 3) matrix type and fibre nature.
In this context, the aim of the research carried out by the authors is to investigate on the bearing failure mode of a laminate bolted joint and, in particular, to underline the effects of the fibre inclination angle, the laminate stacking sequence and the bolt diameter on the aforementioned failure mode.
For the experimental tests circular specimens have been used, with 300mm in diameter, built-in at the edge with a central hole.
Some results, in terms of fiber inclination angle and laminate stacking sequence, have been just published by the authors in [15, 16]. The experimental results, showing the influence of bolt diameter on the bearing strength, represent the subject of the present paper.
In order to perform the experimental investigation, two types of GFRP laminates were tested: unidirectional and cross-ply. In particular the stacking sequence of the unidirectional laminates (10mm thick) was [CSM/08/CSM], while for the cross-ply laminates were used two different stacking sequence . These latter were: [(CSM/06/906)s] and [(CSM/03/903)2]s, where the number of plies and the thickness (12mm) was constant.
On both types of laminates three different values of the bolt diameter have been considered: 20mm, 19mm and 18mm. All of them are relative to the same value of the hole diameter, equal to 21mm.
The experimental results have shown that the bearing strength depends significantly on the bolt diameter for both types of laminates considered.
In particular, in the case of unidirectional laminates the experimental analysis carried out put in evidence a reduction of the bearing strength, passing from the maximum diameter considered of 20mm to the minimum one of 18mm, equal to 13%.
For what concerns the cross-ply laminates the analysis also shows a reduction of the bearing strength equal to 24%, replacing the bolt of 20mm in diameter with one of 18mm, as in the case of unidirectional laminates.
For both types of laminates considered, the analysis shows that the bearing strength reduction, varying the bolt diameter, is independent from the fiber inclination angle as well as from stacking sequence.
Finally, the authors give a new design formula for the bearing failure load, which takes into account, near the fiber inclination angle and the stacking sequence, the bolt diameter also
A New Integration Algorithm for the von-Mises Elasto-Plastic Model
No full textWe introduce a new numerical time integration scheme, in the
framework of associative von-Mises plasticity with linear kinematic and
isotropic hardening. The new procedure is based on the model reformulation
in terms of an augmented stress tensor and on the adoption of an integration
factor; the integration of the model makes use of exponential maps. A
consistent number of numerical tests enlighten the superior behaviour of the
new exponential-based technique, by means of comparison with classical return
map algorithms based either on backward Euler or generalized midpoint
integration rules
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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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