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Material Penyusun dan Formula Campuran Beton untuk Produk PCI Girder
Get PDFAbstract — Concrete is a composite building material made from fine aggregate (sand), coarse aggregate (split), cement as a binder, water, concrete admixtures, and additional admixtures such as fly ash, used as needed. Material testing on concrete is divided into two categories: fine aggregate testing and coarse aggregate testing. Fine aggregate testing includes mud content, organic content, fine modulus, unit weight, specific gravity, and absorption rate. Meanwhile, coarse aggregate testing includes mud content, grading to determine coarseness, unit weight, specific gravity, and absorption rate. The purpose of this study is to determine the impact of using fly ash on the constituent materials and concrete mix formulas for PCI Girder products. SNI method is used for the Job Mix Formula (JMF) mixture in this research. The effectiveness of concrete is measured by the ability of the mix to achieve or exceed the specified strength target. In this context, Trial Mix 1 is superior because it achieves higher strength. However, in terms of cost efficiency, Trial Mix 2 is more economical and sustainable, although it has lower strength but still meets the design target. Trial Mix 2 is considered more efficient overall because it meets the strength target at a lower cost and promotes the use of more sustainable materials
STUDI PERILAKU KUAT GESER BALOK BETON BERTULANG MEMADAT SENDIRI DENGAN SERAT “POLYPROPYLENE”
Get PDFThis paper presents a study of the behavior of self compacting reinforced concrete with polypropylene fiber. Four self
compacting reinforecd concrete beam specimens were cast and tested in this study. Two beams were cast without fiber
and two beams were cast with polypropylene fiber. The proportion of polypropylene fiber was 0.9 kg/m
of the weight
of concrete and the proportion of silica fume was 10 % of the weight of portland cement. The dimension of the beam was
(180×260) mm with 2000 mm length. Two longitudinal bars with Ø10 mm were placed at the top of the beam as
compressive bars and three longitudinal bars with Ø10 mm were placed at the bottom of the beam as tensile bars. Shear
reinforcement with Ø8 mm with spacing of 150 mm were placed at the midle, and there were no stirrups at the shear
region. Several cylinder specimens with size of (150×300) mm and beam without reinforcement with size of
(200×200×700) mm were also cast and tested to determine the mechanics properties of concrete such as compressive
strength, tensile strength, modulus of elasticity and modulus of ruptures. The result show that the compressive strength
and modulus of elasticity of self compacting concrete with polypropylene fiber were decreased 26.98 % and 9.98 %,
respectively compare to the self compacting concrete without fiber. While the tensile strength and modulus of ruptures
of the self compacting concrete with polypropylene fiber were increased 2.76 % and 3.65 %, respectively compare to the
self compacting concrete without fiber. The shear capacities of the self compacting concrete beams without fiber were
62.76 kN and 63.44 kN. While the shear capacities of the self compacting concrete beams with polypropylene fiber were
60.77 kN and 50.61 kN
WAKTU GETAR STRUKTUR BANGUNAN GEDUNG DENGAN PEREDAM GETAR EKSTERNAL FLUID VISCOUS DAMPER
Get PDFStruktur bangunan tahan gempa menjadi solusi dalam perencanaan struktur. Salah satu  solusi yang digunakan untuk meningkatkan kinerja struktur bangunan adalah dengan pemasangan Fluid Viscous Damper (FVD). Penelitian ini menunjukkan waktu getar struktur dengan penambahan FVD pada sudut-sudut gedung. Struktur gedung yang dibahas adalah struktur gedung beton bertulang 10 lantai berukuran 35 x 35 m dengan fungsi bangunan sebagai perkantoran. Lokasi penempatan Fluid Viscous Damper (FVD) diaplikasikan pada sudut-sudut bangunan. Kemudian dilakukan pemodelan struktur 3 dimensi dengan bantuan software ETABS 2018.  Pemodelan struktur dibuat dalam 2 model, yaitu struktur rangka dan struktur dengan Fluid Viscous Damper (FVD). Waktu getar alami struktur didapat dengan bantuan program ETABS 2018. Waktu getar struktur yang didapat dari pemodelan struktur tanpa peredam dan struktur dengan Fluid Viscous Damper. Penggunaan FVD pada struktur gedung memberikan penurunan waktu getar struktur hingga 56% lebih rendah dari sistem struktur rangka pada mode ke-1 dan mode ke-2. Selanjutnya memberikan penurunan waktu getar struktur hingga 89% untuk mode ke-12. Efektifitas penggunaan damper tipe FVD memberikan dampak secara langsung melalui waktu getar struktur
WAKTU GETAR STRUKTUR BANGUNAN GEDUNG DENGAN PEREDAM GETAR EKSTERNAL FLUID VISCOUS DAMPER
Get PDFStruktur bangunan tahan gempa menjadi solusi dalam perencanaan struktur. Salah satu  solusi yang digunakan untuk meningkatkan kinerja struktur bangunan adalah dengan pemasangan Fluid Viscous Damper (FVD). Penelitian ini menunjukkan waktu getar struktur dengan penambahan FVD pada sudut-sudut gedung. Struktur gedung yang dibahas adalah struktur gedung beton bertulang 10 lantai berukuran 35 x 35 m dengan fungsi bangunan sebagai perkantoran. Lokasi penempatan Fluid Viscous Damper (FVD) diaplikasikan pada sudut-sudut bangunan. Kemudian dilakukan pemodelan struktur 3 dimensi dengan bantuan software ETABS 2018.  Pemodelan struktur dibuat dalam 2 model, yaitu struktur rangka dan struktur dengan Fluid Viscous Damper (FVD). Waktu getar alami struktur didapat dengan bantuan program ETABS 2018. Waktu getar struktur yang didapat dari pemodelan struktur tanpa peredam dan struktur dengan Fluid Viscous Damper. Penggunaan FVD pada struktur gedung memberikan penurunan waktu getar struktur hingga 56% lebih rendah dari sistem struktur rangka pada mode ke-1 dan mode ke-2. Selanjutnya memberikan penurunan waktu getar struktur hingga 89% untuk mode ke-12. Efektifitas penggunaan damper tipe FVD memberikan dampak secara langsung melalui waktu getar struktur
Flexural Strength of Self Compacting Fiber Reinforced Concrete Beams using Polypropylene Fiber: an Experimental Study
Get PDFOne of the methods to increase the tensile strength of concrete is adding a fiber mat erial into the concrete.
While to reduce a noise in a construction project, a self compacting concrete was a good choices in the project. This paper presents an experimental study of flexural behavior and strength of self compacting fiber reinforced concrete (RC) beams using polypropylene fiber. The micro monofilament polypropylene fibers with the proportion 0.9 kg/m of concrete weight were used in this study. Four beam specimens were cast and tested in this study. Two beams were cast of self compacting reinforced concrete without fiber, and two beams wer e cast of self compacting fiber r einfor ced concret e using polypropylene. The beams specimen had the sect ion of (180×260) mm and the length was 2000 mm. The beams
had simple supported with the span of 1800 mm. The longitudinal r einforcements were using diameter of 10 mm. Two reinforcements of Ø10 mm were put for compressive reinforcement and three reinforcements of Ø10 mm were put for tensile reinforcement. The shear reinforcement was using diameter of 8 mm. The shear reinforcements with spacing of 100 mm were put in the one fourth near to the support and the spacing of 150 mm were put in the middle span. Two points loading were used in the testing. The result shows that the load-carrying capacity of the self compacting reinforced concrete beam using polypropylene was a little bit higher than the self compacting reinforced concret e beam without polypropylene. The increment of load-carrying capacity of self compacting polypropylene fiber reinforced concrete was not so significant because the increment was only 2.80 % compare to self compacting non fiber reinforced concrete. And
from the load- carr ying capacit y- deflection relationship cur ves show that both the self compacting polypropylene fiber reinforced concret e beam and the self compacting non fiber reinforced concrete beam were ductile beams
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
PERILAKU RANGKAK SUSUT TERHADAP LENDUTAN STRUKTUR JEMBATAN BENTANG PANJANG
Get PDFJembatan Lemah Ireng 1 pada ruas jalan Tol Semarang-Bawen terbuat dari beton prategang dengan panjang total 879 m. Pada masa konstruksi dua perbedaan kondisi teknik terhadap rencana, yakni perubahan material pasir dan perubahan perpindahan traveler. Keduanya diduga sebagai penyebab perbedaan elevasi desain dengan elevasi aktual sehingga dilakukan levelling aspal dengan tebal bervariasi. Jembatan ini didesain untuk memenuhi masa layan 100 tahun namun berdasarkan kondisi aktual, diperlukan peninjauan terhadap perilaku dan kuat layan jembatan hingga umur rencana. Dengan pengaruh variasi pembebanan jangka panjang (rangkak susut) dan kondisi perubahan teknis akibat penambahan aspal, penelitian rangkak susut ini perlu dilakukan untuk mengetahui perilaku lendutan pada gelagar boks jembatan hingga umur rencana. Beberapa tahapan pembebanan yang dilakukan adalah menerapkan beban levelling aspal, dan beban rangkak dan susut dengan menggunakan variasi durasi jangka panjang dengan interval 5, 10 , 15, 20, 40, 60, 80 dan 100 tahun. Analisis dilakukan secara linear statik serta memanfaatkan fasilitas Construction Stage Analysis untuk efek time-dependent pada software Midas Civil 2011. Penelitian ini dilakukan dengan hanya meninjau aksi tetap. Perilaku rangkak susut jembatan cukup signifikan di 5 tahun pertama setelah konstruksi selesai. Lendutan maksimum rangkak susut dan total berada di bentang terpanjang (P4-P5) masing-masing sebesar 17,53 dan 25,71 cm. Lendutan yang terjadi hingga umur rencana 100 tahun masih dalam batas izin, namun tetap perlu pengawasan yang terencana. Dampak minimum rangkak susut terhadap total lendutan pada jembatan Lemah Ireng 1 sebesar 45%. Hal ini menunjukkan rangkak susut terhadap defleksi total hingga umur rencana merupakan efek jangka panjang yang relatif besar.</jats:p
PREDIKSI KAPASITAS PENAMPANG KOLOM BETON BERTULANG DENGAN VARIASI DIAMETER TULANGAN
Get PDFReinforced concrete column design is the process of determining the dimensions of the columns and reinforcement required with the appropriate quality of concrete and steel so that they can withstand the planned load to work on the column. Unlike the beam design, which was based on the applied load, it is possible to determine the cross-sectional dimensions and reinforcement requirements directly from the design equation, and the column design process is iterative. A column generally experiences axial forces, shear forces, bending moments, and torsional moments. In this paper, cross-sections of reinforced concrete columns are modelled and analyzed using an android application that can be installed via the play store. The application offered by eigenplus named RCC Column Design version 2.1.12 was released on 17 September 2017. The last updated RCC Column Design application was on 25 March 2018. This paper aims to predict the cross-sectional capacity of reinforced concrete columns with variations in reinforcement diameter. The cross-sectional capacity of the column referred to in this paper is the axial capacity, moment capacity, and shear capacity. Furthermore, the value of the cross-sectional capacity of reinforced concrete columns with variations in the diameter of the reinforcement has been obtained. The values obtained are proposed as predictions in this paper.Desain kolom beton bertulang adalah proses penentuan dimensi kolom dan tulangan yang dibutuhkan dengan mutu beton dan baja yang sesuai, sehingga dapat menahan beban yang direncanakan bekerja pada kolom. Berbeda dengan desain balok dimana berdasarkan beban yang diberikan, dimungkinkan untuk menentukan dimensi penampang dan kebutuhan tulangan secara langsung dari persamaan desain, proses desain kolom bersifat iteratif. Pada umumnya sebuah kolom mengalami gaya aksial, gaya geser, momen lentur dan momen puntir. Dalam tulisan ini penampang kolom beton bertulang dimodelkan dan dianalisis menggunakan aplikasi android yang dapat diinstal melalui play store. Aplikasi yang ditawarkan oleh eigenplus bernama RCC Column Design versi 2.1.12 dirilis pada tanggal 17 september 2017. Aplikasi RCC Column Design terakhir diupdate pada tanggal 25 maret 2018. Tulisan ini bertujuan untuk memprediksi kapasitas penampang kolom beton bertulang dengan variasi diameter tulangan. Kapasitas penampang kolom yang dimaksud dalam tulisan ini yaitu kapasitas aksial, kapasitas momen dan kapasitas geser. Selanjutnya, nilai kapasitas penampang kolom beton bertulang dengan variasi diameter tulangan telah diperoleh. Nilai-nilai yang diperoleh diusulkan sebagai prediksi dalam tulisan ini.
 
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