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Some considerations on the long-term partial interaction behaviour of composite steel-concrete beams using displacement based finite elements
No full textAbstract
This paper presents some of the modelling techniques available in the literature to describe the long-term behaviour of composite steel-concrete beams with partial shear interaction. In particular, the attention is placed on displacement-based formulations. These consist of the finite difference method, the finite element method, the direct stiffness method and analytical solutions. These are derived by means of the principle of virtual work. The finite element method relies on the weak form of the problem while the remaining ones are derived from its strong form. The time-dependent behaviour of the concrete is modelled by means of the Age-adjusted Effective Modulus Method, while the other materials at the cross-section are assumed to be linear-elastic. The main difference between the modelling technique considered is that, while the finite difference method and the finite element method require discretisations in both spatial and time domains to complete a time analysis, the direct stiffness method and the analytical solutions require only the time discretisation. The ability of the proposed formulations to describe the time-dependent behaviour is then discussed using the solutions in closed form as a benchmark. Two different finite elements have been considered and the occurrence of curvature locking problems has been discussed. The comparisons have been carried out for three structural systems, i.e. for simply supported beams, propped cantilevers and fixed ended beams, subjected to a uniformly distributed load and to time effects. For each case, the minimum spatial discretisations required to keep the error within an acceptable tolerance has been identified
Analytical and numerical model for the time-dependent behaviour of composite steel-concrete members with longitudinal and transverse partial interaction
No full textAnalytical and numerical model for the time-dependent behaviour of composite steel-concrete members with longitudinal and transverse partial interactio
Effects of the shear deformability of the steel member in the short- and long-term partial interaction analysis of steel-concrete composite beams
No full textThis paper presents an analytical model for the short- and long-term analysis of steel-concrete composite beams with partial shear interaction due to the deformability of the shear connectors. Its particularity relies on its ability to depict the shear deformability of the steel component. The time-dependent behaviour of the concrete is described by means of the integral type creep law and is implemented in the analysis using the step-by-step procedure. The steel of the reinforcement and joist are assumed to remain in the linear-elastic range. These material representations are assumed to be appropriate at service conditions. The analytical model is derived by means of the principle of virtual work and the numerical solution is obtained using the finite element method. Extensive numerical simulations are carried out on realistic simply supported composite beams to evaluate the effects of the shear deformability of the steel member on the overall structural response. The numerical results obtained with the proposed model are compared to those of the composite beam model with partial shear interaction that does not include the shear deformability of the steel beam in order to (1) de-termine under which conditions shear deformations of the steel component need to be considered in the analy-sis of composite systems; (2) evaluate how these are affected by the shear connection stiffness and by the re-distributions due to the time-dependent behaviour of the concrete slab
Design expressions for the effective width of composite steel-concrete members
No full text'Concrete Solutions 09 : Adding Value in Changing Climates (24th Biennial Conference of the Concrete Institute of Australia) - held: Luna Park, Sydney, 17-19 September 200
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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