1,720,979 research outputs found
Effect of strengthening method and development length on flexural strength of rc beams with steel plates
No full textThe test result of an experimental study on the flexural strength of reinforced
concrete beams strengthened with steel plates is presented. The beams were
simply supported and loaded monotonically with two point loads. The test
variables used in this study were strengthening method and development length
of steel plates. Nine beams without strengthening and nine beams strengthened
with steel plates were tested until the beams reach the flexural failure specified
by crushing of concrete on the top surface of compression region. The test results
show that steel plates increase the capacity of the beam significantly and slightly
increase the flexural stiffness of the beams. In addition, the ultimate load of the
strengthened beams with debonding failure was similar to the beams without
strengthening if the load kept increasing until flexural failure. The test results also
showed that the debonding failure occurred after the steel plate reach the yield
stress value and the development length affects the failure mode of the
strengthened beams. Analytical study based on a theoretical moment-curvature
calculation of reinforced concrete cross-section was carried out in order to obtain
the complete flexural response of the beams analytically. The comparison shows
that analytical prediction provides good accuracy for both reinforced concrete
beams with and without strengthenin
Shear strength of reinforced concrete t-beams without stirrups
No full textThis paper presents the test results of experimental study on shear strength of
reinforced concrete beams without stirrups. The test variables in this study were
type of beam cross section and ratio of longitudinal reinforcement. Six simple
supported beams, consisting of three beams with rectangular cross section and
three beams with T section, subjected to two point load were tested until failure.
During the test, the values of the diagonal crack load and the maximum load were
observed as well as the deformation of the beams. Existing empirical equations
for shear strength of concrete presented in the literature and design codes were
used and then compared to that value obtained from the test. Comparison between
test results and theoretical shear capacity show that all of equations conservatively
estimate the occurrence of shear failure with the values of the test results 10 to
90% higher than the theoretical values. It was confirmed from the test that the
shear capacity of T-beams were higher than for rectangular beams, with the values
ranging from 5 to 25%, depending on the ratio of longitudinal reinforcement.
Also, it was observed that ratio of longitudinal reinforcement influences the shear
capacity of the beam as well as the angle of diagonal shear crack. In addition,
based on the test results, a simple model for predicting the contribution of flange
to shear capacity in T-beam was presented
EFFECT OF STRENGTHENING METHOD AND DEVELOPMENT LENGTH ON FLEXURAL STRENGTH OF RC BEAMS WITH STEEL PLATES
Get PDFThe test result of an experimental study on the flexural strength of reinforced concrete beams strengthened with steel plates is presented. The beams were simply supported and loaded monotonically with two point loads. The test variables used in this study were strengthening method and development length of steel plates. Nine beams without strengthening and nine beams strengthened with steel plates were tested until the beams reach the flexural failure specified by crushing of concrete on the top surface of compression region. The test results show that steel plates increase the capacity of the beam significantly and slightly increase the flexural stiffness of the beams. In addition, the ultimate load of the strengthened beams with debonding failure was similar to the beams without strengthening if the load kept increasing until flexural failure. The test results also showed that the debonding failure occurred after the steel plate reach the yield stress value and the development length affects the failure mode of the strengthened beams. Analytical study based on a theoretical moment-curvature calculation of reinforced concrete cross-section was carried out in order to obtain the complete flexural response of the beams analytically. The comparison shows that analytical prediction provides good accuracy for both reinforced concrete beams with and without strengthening
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
STUDI EKSPERIMENTAL REHABILITASI DAN REKONSTRUKSI STRUKTUR GEDUNG BERTINGKAT BETON BERTULANG PASCA GEMPA
Get PDFKonstruksi beton bertulang banyak digunakan untuk struktur gedung bertingkat. Struktur beton bertulang harus direncanakan kekuatannya agar mampu memikul beban yang direncanakan. Dalam masa layan struktur beton bertulang sangat lama, biasanya lebih dari 20 tahun, berkemungkinan struktur tersebut mengalami beban yang sangat besar seperti beban gempa terutama didaerah dengan intensitas gempa tinggi. Akibat beban besar ini struktur gedung juga berkemungkinan mengalami kerusakan.
Bagian dari struktur seperti balok, kolom dan sambungan balok-kolom tidak boleh mengalami kerusakan berat akibat beban yang besar karena sambungan ini merupakan bagian yang sangat penting pada struktur bangunan gedung bertingkat. Kerusakan yang terjadi pada komponen-komponen struktur yang tidak mengalami kerusakan terlalu parah biasanya dapat direhabilitasi.
Pemakaian pelat baja dan Carbon Fiber Reinforced Polymer (CFRP) pada permukaan balok, kolom dan sambungan balok-kolom beton bertulang sebagai salah satu metode untuk rehabilitasi mulai populer akhir-akhir ini. Pelat baja merupakan bahan rehabilitasi struktur gedung yang cukup ekonomis namun masih mempunyai beberapa kelemahan. Sementara CFRP merupakan bahan yang ringan, memiliki kekuatan tarik sangat tinggi dan tahan terhadap korosi. Bahan ini juga dapat digunakan sebagai pilihan untuk rehabilitasi struktur gedung bertingkat.
Meskipun telah banyak cara untuk melakukan perkuatan atau rehabilitasi struktur gedung bertingkat yang rusak pasca gempa namun sampai saat ini belum ada pedoman atau tuntunan yang jelas untuk melakukannya. Sehingga perlu dibuat suatu panduan agar rehabilitasi struktur gedung bertingkat dapat dilakukan dengan acuan yang jelas. Panduan atau peraturan seharusnya dihasilkan dari serangkaian pengujian dan penelitian sehingga dapat diterima oleh masyarakat luas. Oleh karena itu sangat perlu untuk melakukan penelitian tentang rehabilitasi dan rekonstruksi struktur gedung bertingkat beton bertulang pasca gempa.
Berdasarkan uraian diatas, pada penelitian ini akan dilakukan studi eksperimental untuk melihat perilaku kerusakan komponen struktur beton bertulang akibat pembebanan yang besar. Setelah itu dilakukan rehabilitasi atau perkuatan untuk melihat kemampuannya dalam menahan beban pasca rehabilitasi. Selanjutnya akan disusun sebuah panduan untuk melakukan perkuatan atau rehabilitasi struktur gedung bertingkat yang rusak pasca gempa
EFFECT OF END ANCHORAGE LENGTH AND STIRRUP RATIO ON BOND AND SHEAR CAPACITY OF CONCRETE BEAMS WITH NONMETALLIC REINFORCEMENT
No full textThis paper presents a study on the effect of end anchorage length and stirrup ratio on bond and shear capacity of concrete beams reinforced with Carbon Fiber Reinforced Polymer (CFRP) bars. This study was carried out using test data on nine simply supported reinforced concrete beams with stirrups. The
beams were subjected to two point monotonic loads and the test variables were the length of end anchorage and the stirrup ratio. Theoretical equations for calculating bond strength and shear capacity obtained from literature were applied and then compared with experimental values. Beams with inadequate end anchorage length showed premature bond failure even when there was
sufficient stirrup ratio. Beams with adequate end anchorage length failed in shear or flexure modes depending on the stirrup ratio. A numerical model for bond stress and slip in response to pullout forces was also used to determine analytically the bond stress distributions along end anchorage. The behavior of tensile force acting on the stirrups was also examined. Finally, a simple model
for predicting tension force acting on the stirrups was proposed
Flexural and Bond Behavior of Reinforced Concrete Beams with FRP Bars
No full text豊橋技術科学大学博士(工学)thesi
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
- …
