1,721,000 research outputs found
Hybrid Reinforcement (Rebars + Fibers) for elevated slabs
No full textWhen designing Fiber Reinforced Concrete (FRC) structures, one of the basic issues is represented by
the choice of a proper combination of fibers and conventional reinforcement that allows to obtain the
best structural performance with the minimum amount of materials. The combination of rebars and
fibers in the concrete matrix is generally known as Hybrid Reinforced Concrete (HRC). HRC represents
a feasible solution in many structures; among these, slabs are gaining an increasing interest among
practitioners. In fact, slabs are the most widespread structural elements in common practice since they
are typically used to construct industrial floors (slab on grade), foundations (slab on piles) or floors
(elevated slabs).
This paper focuses on the design of FRC elevated slabs by using the most recent design provisions
reported in the fib Model Code 2010. Emphasis will be given at the use of HRC for optimizing the slab
reinforcement. In more detail, the results of a parametric study performed to design the Hybrid
Reinforcement for elevated slabs will be presented and discussed and a procedure for designing the
Hybrid Reinforcement will be proposed and verified by nonlinear finite element analyses
EXPERIMENTAL STUDY ON STEEL FIBER REINFORCED CONCRETE BEAMS IN PURE TORSION
Full text linkThis paper concerns an experimental study on Steel Fiber Reinforced Concrete (SFRC) beams tested
under pure torsion. The beams are reinforced with longitudinal rebars without any transverse
reinforcement that was substituted by high strength steel fibers.
Experimental results show that SFRC allows a stable torsional behavior after cracking, in terms of
enhanced crack control, increased cracked stiffness and torsional resistance.
In order to predict the response of SFRC beams, an analytical model reported in the literature has been
used and adapted to the fib Model Code 2010 provisions. The results of the model prediction are
compared against the experimental results and critically discussed
Numerical Study of a Full Scale Hollow Brick Masonry Building Strengthened with Steel Fiber Reinforced Mortar Coating
No full textThe typical low tensile resistance of Unreinforced Masonry (URM) generally makes existing building critical to
seismic actions. The development of innovative strengthening and repairing techniques is therefore a crucial topic
to improve the structural safety of existent constructions.
The paper presents the results of non-linear push-over analyses carried out on a full scale URM building to assess
the structure response in case Steel Fiber Reinforced Mortar (SFRM) coating is used as a seismic retrofitting
technique.
In order to calibrate the smeared crack model used for the simulation of the building, some full scale walls tested
within the present research program have been preliminary simulated.
The numerical study of the building is performed to predict the response of a real full scale specimen that will be
tested at the University of Brescia under reverse cyclic loading conditions. In view of this, the global response of
the building before and after the application of a single layer of SFRM coating has been studied and discussed. The
simulations included also the addition of proper steel connections between the SFRM coating and the concrete
foundation of the building
Full Scale Tests on Hollow Brick Masonry Walls Repaired with Steel Fiber Reinforced Mortar Coating
No full textAn experimental study on 3 m long and 2 m high Unreinforced Masonry (URM) walls repaired or strengthened
with thin Steel Fiber Reinforced Mortar (SFRM) coating is presented. The samples are made with hollow-clay
brick masonry having mechanical properties typical of existing masonry buildings constructed in Italy between the
‘50s and ‘70s of the 20th century. The walls are subjected to a constant vertical load combined with a lateral reverse
cyclic quasi-static load.
Unlike traditional strengthening coating techniques, the one herein proposed adopts a thinner thickness (25 mm)
and high strength short steel fibers as a reinforcement uniformly spread within the mortar matrix. The SFRM
overlay is anchored to the masonry surface by nylon wall plugs with steel screws (~9 connectors/m2) drilled into
masonry units.
The study includes a total of four tests: two on unstrengthened walls and two on the previous specimens, repaired
and reinforced with SFRM coating on both sides. A novel feature is represented by a series of steel rebars placed
along the wall base to anchor the SFRM coating to the wall foundation.
The experimental results show the strength and stiffness improvement provided by the proposed technique.
Moreover, a critical discussion on the effectiveness of the coating-to-foundation connection is reported
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
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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