1,720,963 research outputs found
Load testing and model simulations for a stone arch bridge
No full textService and high level load tests on a typical single span stone arch bridge in the south of Ireland and an associated set of three-dimensional nonlinear numerical analyses are discussed in this paper. The three-dimensional finite element models, which were generated using a commercially available finite element package, include the arch fill and a frictionless contact interface between this fill and the spandrel walls modelled with a nonlinear smeared crack material model. While this modelling strategy has been previously corroborated for service load levels, the results of the numerical model (which are compared with results from the experimental tests) also demonstrate the suitability of this modelling strategy at higher load levels. Finally, the suitability of three-dimensional solid models in the context of stone arch bridge assessment is discussed
Test Methods For Frp-concrete Systems Subjected To Mechanical Loads - State-of-the-art Review
No full textThis report addresses the methodology for determining the long-term behavior of bridge structures reinforced with fiber reinforced plastic (FRP) rods. In particular, a review of the existing literature on what has been done and what needs to be done for the development of accelerated test methods, with emphasis on mechanical loads, is presented. The focus of the report is on new, bonded FRP reinforcement for concrete bridge structures. Companion reports address stand-alone FRP systems subjected to mechanical loads, and stand-alone FRP and FRP-concrete systems subjected to environmental loads
Analysis of bonding mechanisms of smooth and lugged FRP rods embedded in concrete
No full textThe bond behavior of two fundamental types of FRP reinforcement for concrete-smooth rods and lugged rods-has been investigated by examining experimental data and developing detailed finite-element models of these simple rod/concrete systems. The bond controlling parameters, identified by direct pull-out tests on embedded rods, were built into the models so that analytical studies of the effect of each parameter on bond could be carried out. The viability of the finite-element models, created by the use of commercial finite-element programs, was verified by comparing the predicted and experimentally obtained load versus slip and/or load versus longitudinal strain data. The models were used to predict the behavior of environmentally degraded rods. The moire' method of strain analysis was used to investigate full-field, local strain distributions in flat, lugged rods embedded on the surface of concrete. (C) 1998 Elsevier Science Ltd. All rights reserve
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Effect of environmental pre-conditioning on bond of FRP reinforcement to concrete
No full textTo determine how environment affects the bond behavior of FRP reinforcement for concrete, FRP rods were subjected to accelerated environmental pre-conditioning and several mechanical tests. Specially-made smooth and lugged FRP rods consisting of glass/vinylester, carbon/vinylester, and carbon/epoxy composites were evaluated. The primary means of comparison of the pre-conditioned materials was the direct pull-out test, although pertinent properties of rods such as short-beam apparent shear strength and longitudinal modulus of elasticity were also evaluated. The results reveal that pre-conditioning of FRP rods prior to casting degrades the FRP material itself, but does not necessarily degrade the bond behavior. In particular, the smooth rods, which had low bond strength to begin with, had little change in bond strength. On the other hand, the lugged rods, which were made susceptible to the environment by the machining of lugs, had significantly reduced bond strength due to degradation of the resin or the fiber/resin interface. Of the three types of aqueous environments evaluated, high temperature combined with an alkaline solution is the most aggressive to the FRP materials evaluated. Certain experiments highlighted the importance of the resin rich surface on environmental resistance
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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