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Pengaruh Penambahan Serat Bambu Terhadap Kuat Tarik dan Kuat Tekan Beton
Get PDFConcrete is one of construction material that has been used widely for many years.The advantages of using concrete as contruction materials are it has high compressive strength,easy to be molded, no need professional labours and the constituent materials of concrete arecheap and easy to get. Beside of those advantages, concrete also has disadvantage such as haslow tensile strength. Its tensile strength is only about 10% from its compressive strength. Manyprevious research has been conducted to increase the tensile strength of concrete. In late 1960s,fiber concrete has been researched to be the solution to increase the tensile strength of concrete.Types of fiber concrete are steel fiber, glass fiber, synthetic fiber and natural fiber. Naturalfiber concrete such as bamboo has low manufacturing cost than the other types of fiber. Theaimed of this research is to investigate the influence of bamboo fiber concrete on the tensilestrength and the compressive strength of concrete. The percentage of bamboo fiber were variedfrom 0%, 1%, 2% and 3% by cement material. The test results showed that bamboo fiberconcrete increase the tensile strength test and compressive strength test result. The highesttensile strength was 12,4 MPa in 28 days obtained by mixture that contained 2% of bamboofiber. The highest compressive strength concrete was 28,3 MPa in 28 days from the mixtureswith 1% of bamboo fiber.Keywords: concrete, fiber concrete, bamboo fiber concrete, compressive strength, tensilestrengt
Self Compacted Concrete Dan Grouting Dari Beton Geopolymer
Get PDFBeton geopolymer adalah beton yang tidak menggunakan semen sebagai binder. Oleh karena itu, beton geopolymer dipandang sebagai salah satu solusi dalam pemecahan masalah peningkatnya pemanasan global akibat produksi semen Portland dan diharapkan menjadi alternatif baru selain beton konvensional. Beton geopolymer segar mempunyai sifat kekentalan yang kaku sehingga kondisinya tidak workable, padahal dalam proses pengecoran, workabilitas beton sangat dibutuhkan untuk mempermudah pelaksanaan di lapangan. Untuk mengatasi masalah workabilitas, telah ditemukan salah satu inovasi beton yaitu Self Compacted Concrete (SCC). SCC adalah campuran beton yang dapat memadat sendiri tanpa menggunakan alat pemadat (vibrator) (Sugiharto, Kusuma, Himawan, Dharma, 2001). Beberapa metoda yang telah diterapkan Okamura dan Ouchi (2003) untuk memperoleh sifat beton yang self-compactibility adalah : membatasi kandungan agregat, rasio water-powder yang rendah dan penggunaan bahan additive seperti superplasticizer. Diharapkan dengan penambahan superplasticizer, sifat geopolymer bisa menjadi lebih workable dan mempunyai waktu setting yang lebih panjang. Akan tetapi setelah dilakukan penelitian, ternyata hasil yang diperoleh adalah penambahan superplasticizer baik yang berbasis naphtelene sulphonated dan polycarboxylic ether hyper plasticizer tidak mempengaruhi waktu setting binder secara signifikan. Binder geopolymer tetap mempunyai waktu setting yang relatif cepat. Dengan waktu setting yang sangat cepat sangat sulit untuk membuat geopolymer dalam skala besar, sehingga disimpulkan aplikasi geopolymer untuk self compacted concrete sangat sulit diwujudkan dan dilaksanakan. Sehingga disimpulkan bahwa geopolymer lebih cocok digunakan untuk grout, karena skala pekerjaan yang dibutuhkan untuk grout jauh lebih kecil jika dibandingkan dengan skala untuk pekerjaan beton. Selain itu, sifat pasta geopolymer flow sehingga lebih cocok untuk pekerjaan grouting. Injection atau pressure grouting adalah proses memasukkan atau menginjeksikan material cementitious ke dalam tempat yang tidak dapat dicapai seperti di bawah pondasi struktur untuk tujuan menutup lapisan, retak dan celah atau mengisi rongga (Shroff, Shah, 1993). Variasi yang digunakan dalam penelitian ini adalah variasi molaritas (6Mt 8M dan 10 M) dan penambahan superplasticizer sampai 3 %. Dari hasil penelitian, temyata kuat tekan tertinggi adalah pada campuran tanpa penambahan superplasticizer. Kuat tekan tertinggi pasta geopolimer terdapat pada campuran MI0CAI.5SP0 yaitu 104,46 pada umur 28 hari dan kuat tekan tertinggi mortar geopolimer terdapat pada campuran M10CA1.5SP0 yaitu 71 pada umur 28 hari
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Geopolymer concrete is concrete that does not use cement as a binder. Therefore, geopolymer concrete is seen as one solution in solving the problem of increasing global warming due to Portland cement production and is expected to become a new alternative to conventional concrete. Fresh geopolymer concrete has a stiff viscosity so that it is not workable, even though in the casting process, concrete workability is needed to facilitate implementation in the field. To overcome workability problems, one concrete innovation has been discovered, namely Self Compacted Concrete (SCC). SCC is a concrete mixture that can compact itself without using a compactor (vibrator) (Sugiharto, Kusuma, Himawan, Dharma, 2001). Several methods that have been applied by Okamura and Ouchi (2003) to obtain self-compactible concrete properties are: limiting aggregate content, low water-powder ratio and the use of additive materials such as superplasticizers. It is hoped that with the addition of superplasticizer, the geopolymer properties can become more workable and have a longer setting time. However, after conducting research, it turned out that the results obtained were that the addition of superplasticizers, both based on sulphonated naphthelene and polycarboxylic ether hyper plasticizer, did not significantly affect the setting time of the binder. Geopolymer binder still has a relatively fast setting time. With a very fast setting time, it is very difficult to make geopolymer on a large scale, so it can be concluded that the application of geopolymer for self-compacted concrete is very difficult to realize and implement. So it is concluded that geopolymer is more suitable for grouting, because the scale of work required for grouting is much smaller compared to the scale for concrete work. In addition, the flow properties of geopolymer paste make it more suitable for grouting work. Injection or pressure grouting is the process of inserting or injecting cementitious material into places that cannot be reached such as under the foundation of a structure for the purpose of covering layers, cracks and gaps or filling cavities (Shroff, Shah, 1993). The variations used in this research were variations in molarity (6Mt 8M and 10 M) and the addition of superplasticizer up to 3%. From the research results, it turns out that the highest compressive strength is in the mixture without the addition of superplasticizer. The highest compressive strength of geopolymer paste is found in the MI0CAI.5SP0 mixture, namely 104.46 at the age of 28 days and the highest compressive strength of the geopolymer mortar is found in the M10CA1.5SP0 mixture, namely 71 at the age of 28 day
Analisis Kinerja Struktur Gedung Perkantoran Pabrik Pupuk Gresik dengan Pembebanan Gempa Berdasarkan SNI 1726:2019 terhadap Simpangan Antar Lantai dan Pengaruh P-Delta
Get PDFEarthquakes are natural phenomena caused by natural events. The strength of an earthquake can be measured using a seismometer. The most commonly used scale to measure the strength of an earthquake is the Richter scale. The amount of demage caused by an earthquake is not only determined based on its strength, but is also measured by the area where the earthquake occurs. The depth of an earthquake that occurs from within the earth can also affect the potential damage. Eatrhquakes are located close to the groound surface, so they can have significant destructive properties. Large earthquake can usually trigger aftershocks, so they can be overcome using temporal processes.This research carried out an analysis of story drift and the influence of P-Delta on the reinforced concrete structure of the office building PT. Pupuk Lapan Harsa based on SNI 1726:2019. With the planning concept using the help of SAP2000 software.The results of the analysis of the Gresik fertilizer factory office building were delcared safe with a story drift in the x-axis ( ) in the amount of 10,95 mm up to 31,85, in the y-axis ( ) in the amount of 10,95 mm up to 31,85 mm. Meanwhile, the value of the influence of P-Delta in the x-axis ( ) in the amount of 0,007 up to 0,036, in the y-axis ( ) in the amount of 0,007 up to 0,036.
Earthquakes are natural phenomena caused by natural events. The strength of an earthquake can be measured using a seismometer. The most commonly used scale to measure the strength of an earthquake is the Richter scale. The amount of demage caused by an earthquake is not only determined based on its strength, but is also measured by the area where the earthquake occurs. The depth of an earthquake that occurs from within the earth can also affect the potential damage. Eatrhquakes are located close to the groound surface, so they can have significant destructive properties. Large earthquake can usually trigger aftershocks, so they can be overcome using temporal processes.This research carried out an analysis of story drift and the influence of P-Delta on the reinforced concrete structure of the office building PT. Pupuk Lapan Harsa based on SNI 1726:2019. With the planning concept using the help of SAP2000 software.The results of the analysis of the Gresik fertilizer factory office building were delcared safe with a story drift in the x-axis ( ) in the amount of 10,95 mm up to 31,85, in the y-axis ( ) in the amount of 10,95 mm up to 31,85 mm. Meanwhile, the value of the influence of P-Delta in the x-axis ( ) in the amount of 0,007 up to 0,036, in the y-axis ( ) in the amount of 0,007 up to 0,036
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
Studi Perencanaan Struktur Atas Jembatan Semanding Tuban Dengan Menggunakan Struktur Rangka Baja
Get PDFThis study aims to plan the superstructure of a steel frame bridge using K-truss type. The bridge that will be planned in this project has a span of 36 meters and the width of the bridge is 11 meters, located at stations 10+436.80 to stations 10+401 located at over the Semanding River and connects Tunah Village, Semanding District to the Village Prudara Kulon, Semanding District, Tuban. Design of steel structures using the Load and Resistance Factor Design (LRFD) approach. The planning of this bridge was assisted by Autocad software and SAP200 V22. The steel profile on the longitudinal girder is IWF 250 x 125 x 6 x 9 and for IWF transverse girders 1000 x 350 x 18 x 38. Longitudinal and transverse girders using a composite beam system. The main frame profile uses IWF 400 x 400 x 21 x 21, and IWF diagonal girders 400 x 400 x 21 x 21. Connections used on longitudinal girders and transversely, the connecting device is a bolt with a diameter of 20 mm and welding. Whereas the connection on the main frame is a gusset connection with the connecting device being a bolt 20 mm in diameter
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