Articles

PERILAKU PERAMBATAN RETAK PADA ALUMINIUM PADUAN A2024-T351 DENGAN MENGGUNAKAN SPESIMEN CTS Husaini, Husaini
Jurnal Teknik Mesin Vol 9, No 1 (2007): APRIL 2007
Publisher : Institute of Research and Community Outreach - Petra Christian University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (892.912 KB) | DOI: 10.9744/jtm.9.1.pp. 9-17

Abstract

Fracture behavior of aluminum alloys under mixed mode (Mode I+II) loading was studied. Fracture tests were carried out on A2024-T351 aluminum. Compact-tension-shear specimen was employed and angle between loading axis and the crack surface was varied from 90°(mode I) to 0°(mode II). The crack extension (crack initiation and propagation) behaviors observed by a video microscope. Under a load with relatively high mode II components, the shear type crack initiation preceded the opening type crack propagation. Final fracture was occurred by shearing instability in the pure mode II loading. These experimental results were explained qualitatively by using finite element analysis. The critical values of stress intensity factors at crack initiation under mode II dominant conditions become smaller than those predicted by the maximum hoop stress criterion. It was also found that the rolling direction and small holes existing ahead of the crack-tip influence the crack extension behaviors. Abstract in Bahasa Indonesia : Penelitian ini membahas studi tentang perilaku retak aluminium paduan pada pembebanan mode campuran (mixed mode) (Mode I+II). Uji retakan dilakukan pada material aluminium paduan A2024-T351. Sudut antara arah pembebanan dan permukaan retakan dari spesimen Compact-tension-shear yang digunakan divariasikan dari 90°(mode I) sampai 0°(mode II). Perilaku dan arah perambatan retak diamati dengan video microscope. Pada pembebanan dengan komponen mode II relatif tinggi, maka inisiasi retakan jenis geseran terjadi lebih dahulu kemudian diikuti dengan jenis perambatan retak terbuka. Patah akhir terjadi karena ketidakstabilan geseran pada pembebanan mode II. Hasil eksperimental ini akan dijelaskan secara kualitatif dengan menggunakan analisa metode elemen hingga. Harga kritis dari faktor intensitas tegangan pada inisiasi retakan pada pemebebanan dimana mode II lebih dominan menjadi lebih kecil dari pada yang diprediksikan dengan kriteria tegangan hoop maksimum (maximum hoop stress criterion). Juga diperoleh bahwa arah pengerolan dan lubang-lubang kecil yang ada didepan ujung retak mempengaruhi perilku arah perambatan retak. Kata kunci: Aluaminum paduan, perilaku perambatan retak, analisa FEM, pembebanan mode campuran.
ANALISIS DINAMIS RIWAYAT WAKTU JEMBATAN GANTUNG AKIBAT PEJALAN KAKI DAN KENDARAAN RODA DUA Edhi, Sarwo; Hasan, Muttaqin; Husaini, Husaini
JURNAL TEKNIK SIPIL Vol 1, No 4 (2018): Volume 1 Special Issue, Nomor 4, Februari 2018
Publisher : Jurusan Teknik Sipil, Fakultas Teknik, Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (332.909 KB) | DOI: 10.24815/jts.v1i4.10046

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Abstract : Suspended footbridges has a lot of constructed in Indonesia to access many?especially rural-regions. Due to its flexiblity, understanding and design of the suspension bridge is not enough to rely on static analysis. This paper deal with the dynamic behaviour of simply unstiffening suspended bridges subjected to pedestrian load and motor-cycles moving load.As the SNI 03-3428-1994 codeof the technical planning for pedestrian suspension bridge is not set in consideration of dynamic analysis and design,pedestrian-load model is based on British Standard BS 5400-4: 1990 and Eurocode EN1991-2:2003. Modeling pedestrian load is done in three conditions; single pedestrian, group, and crowd. The motor-cycles moving load is modeled as a moving force model, accurate for low speed. Variations in the speed used was 10 km / h, 20 km / h, 30 km / h are considered representative. Dynamic analysis done by the time history Newmark direct integration method with the help of finite element analysis program SAP2000 v.15. Span 60 m, 80 m and 100 m was studied. As these results, dynamic interaction between the bridges and pedestrian load is not significant.The analyses have shown that the responses greatly differ between the British Standard and Eurocode.However, motor-cycle load has same results but higher  with the largest DAF value 7.27% for speeds of 30 km / h interval of 2 seconds on a span of 100 m. Abstrak: Jembatan gantung pejalan kaki telah banyak sekali dibangun di Indonesia, sebagai pemecah masalah akses antar wilayah. Dikarenakan strukturnya yang fleksible, pemahaman dan desain jembatan gantung tidak cukup sekedar mengandalkan analisis statis. Tujuan penelitian ini adalah untuk memperlihatkan respons dinamis jembatan gantung pejalan kaki sederhana tanpa pengaku. Hal yang akan dipelajari adalah simpangan vertikal dan percepatan ditinjau dari sisi kenyamanan. Beban yang dikenakan adalah beban pejalan kaki dan kendaraan roda dua. Dikarenakan SNI 03-3428-1994 Tata cara perencanaan teknik jembatan gantung untuk pejalan kaki tidak mengatur analisis dinamis dalam pertimbangan analisis dan desain, pemodelan beban pejalan kaki didasarkan pada British Standard BS 5400-4:1990 dan Eurocode EN1990. Pemodelan beban pejalan kaki dilakukan dalam tiga kondisi; pejalan tunggal, pejalan kelompok, dan arus keramaian. Untuk beban kendaraan dimodelkan sebagai beban berjalan yang cukup akurat untuk kecepatan rendah. Variasi kecepatan yang digunakan adalah 10 km/jam, 20 km/jam, 30 km/jam dianggap cukup representatif. Analisis dinamis dilakukan secara riwayat waktu dengan metode integrasi langsung Newmark dengan bantuan program analisa elemen hingga SAP2000 v.15. Bentang yang diteliti adalah 60 m, 80 m dan 100 m. Dari hasil tersebut didapati bahwa percepatan akibat beban pejalan kaki masih kecil sehingga tak berpengaruh secara signfikan. Sedangkan beban sepeda motor juga demikian, dengan nilai DAF terbesar 7,27 % untuk kecepatan 30 km/jam selang 2 detik pada bentang 100 m.
ANALISIS DEFORMASI DAN RETAKAN STRUKTUR TEROWONGAN DENGAN PEMODELAN PSEUDOSHELL Abdullah, Nirwal Mahdi; Hasan, Muttaqin; Husaini, Husaini
JURNAL TEKNIK SIPIL Vol 6, No 3 (2017): Volume 6, Nomor 3, Mei 2017
Publisher : Jurusan Teknik Sipil, Fakultas Teknik, Universitas Syiah Kuala

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Abstract

Abstract: The increasing development of infrastructure such as building tunnels in support of improved transport system that takes some analysis of the behavior of the tunnel in preventing damage. The object of research is the shotcrete lining tunnel Sieberg, Austria developed using construction methods New Austrian Tunnel Method (NATM). This study aims to determine the behavior that causes damage such as cracks and displacement by performing two analyzes are analyzed using a pseudoshell model developed by Shi (2009) with a thickness of pseudoshell is 0.06 m. Some of the data used was taken from a previous study conducted by Lackner and Mang (2003) which is also located in the tunnel Sieberg, Austria. Data collected in the form of secondary data will be analyzed using the software ATENA V5. The results obtained are in pseudoshell modeling, for a distributed load partial left side of the tunnel, the amount of deformation modeling pseudoshell thickness 0.06 m is 42,75 mm.Keywords : Tunnels, NATM method, PseudoShell Model, Dummy Load, ATENA V5, Cracked, Displacement.Abstrak: Meningkatnya pembangunan infrastruktur seperti bangunan terowongan dalam mendukung sistem transportasi yang meningkat sehingga diperlukan beberapa analisa terhadap perilaku terowongan dalam mencegah terjadinya kerusakan. Objek penelitian adalah lapisan shotcrete terowongan Sieberg, Austria yang dikembangkan dengan menggunakan metode konstruksi New Austrian Tunnel Methode (NATM). Penelitian ini bertujuan mengetahui perilaku yang menyebabkan kerusakan seperti retakan dan displacement dengan melakukan analisis yaitu menggunakan model Pseudoshell yang dikembangkan oleh shi (2009) dengan ketebalan pseudoshell sebesar 0,06 m. Beberapa data yang digunakan diambil dari penelitian sebelumnya yang dilakukan oleh Lackner dan Mang (2003) yang juga berlokasi di terowongan Sieberg, Austria. Data yang dikumpulkan berupa data sekunder yang akan dianalisa menggunakan perangkat lunak ATENA V5. Hasil yang diperoleh adalah pada pemodelan pseudoshell, untuk beban merata sebagian sisi kiri terowongan, besaran deformasi dengan pemodelan pseudoshell dengan tebal 0,06 m adalah 42,75 mm.Kata kunci : Terowongan, Metode NATM, Pemodelan Pseudoshell, Beban Dummy, ATENA V5, Retak, Displacement.
UPGRADING OF TAYAN’S CRUDE BAUXITE USING ROTARY DRUM SCRUBBER Husaini, Husaini; Cahyono, Stefanus Suryo; Damayanti, Retno
Indonesian Mining Journal Vol 17, No 1 (2014): INDONESIAN MINING JOURNAL Vol. 17 No. 1 FEBRUARY 2014
Publisher : Puslitbang tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (965.294 KB) | DOI: 10.30556/imj.Vol17.No1.2014.343

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Indonesia has abundant bauxite resources at Tayan, West Kalimanatan, where the reserve is relied more than 800 million tons. There were two types of Tayan’s bauxite that have been used in the present research. One contains 34.63 % Al2O3 and 5.20 % reactive SiO2 which is known as low grade ore, while the second type contains 47.30 % Al2O3 and 5.79 % reactive SiO2 which is known as high grade ore. A Rotary Drum Scrubber (diameter 80 cm, length 200 cm, screen opening 2 mm) was applied to upgrade the crude bauxite ores. The research was started by crushing followed by scrubbing and screening. The scrubber is supported by water sprayer to achieve washed bauxite (+2mm of particle sizes) separated from tailing (-2mm of particle size). The researchs were conducted by varying the feed rate (300-2100 kg/hr), solid percentage (14-36%) and water flow rate (35-78 L/minute). The results show that feed rate and solid percentage have high impact to the quality of washed bauxite obtained. The higher is feed rate and solid percentage the lower is alumina content of the washed bauxite produced. An optimum condition is attained at1600 kg/hour of feeding rate, 25% solid and 8 minutes of residence time that is capable to produce washed bauxite with chemical composition of 45.25 % Al2O3 and 3.27 % reactive SiO2 (when the crude bauxite as the feed is low grade type). On the other hand, the washed bauxite obtained with chemical composition of 55.50 % Al2O3, 0.47 % reactive SiO2 and impurities content with particle sizes <2mm is approximately 2,1% (when the crude bauxite as the feed is typically high grade). The average increase of Al2O3 content in the washed bauxite is 6.63% and the average decrease of reactive SiO2 is 2.87%. The washed bauxite produced is reliable as feed material for Bayer process.
DIGESTING AMPAS BAUKSIT UNTUK PEMBUATAN TAWAS SKALA PILOT Hidayat, Kukuh Nur; Husaini, Husaini; Suganal, Suganal
Jurnal Teknologi Mineral dan Batubara Vol 14, No 3 (2018): Jurnal Teknologi Mineral dan Batubara Edisi September 2018
Publisher : Puslitbang tekMIRA

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (648.557 KB) | DOI: 10.30556/jtmb.Vol14.No3.2018.151

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Limbah atau ampas bauksit hasil pencucian belum termanfaatkan dengan optimal dan hanya menimbulkan pencemaran lingkungan, padahal kandungan berharga yang ada di dalamnya seperti alumina masih bisa diolah menjadi koagulan (tawas atau PAC). Tawas dapat dihasilkan melalui proses digesting bauksit dengan menggunakan asam sulfat. Percobaan pembuatan tawas ini menggunakan ampas pencucian bauksit asal Meliau, Kalimantan Barat, berupa undersize rotary drum scrubber (RDS) yang berukuran +60  mesh dan sudah mengalami penggerusan sampai -150 mesh. Tujuan penelitian ini adalah untuk mendapatkan kondisi optimum proses pembuatan tawas skala pilot. Proses ini dimulai dengan proses reduksi bauksit dengan ball mill, dilanjutkan dengan pelarutan bauksit dengan asam sulfat dalam sebuah reaktor pada suhu 100 oC. Filtrat yang dihasilkan direduksi kandungan besinya dengan diuapkan, sehingga menjadi tawas. Setelah dilakukan optimasi pembuatan tawas, kondisi terbaik yang diperoleh pada pembuatan tawas dari ampas adalah untuk berat ampas sebesar 50 kg dibutuhkan asam sulfat sebesar 120,89 kg dan air 3,62 kg yang menghasilkan persen ekstraksi Al2O398,62% pada kondisi suhu 100oC, dengan waktu 1 jam.
HUBUNGAN HYGIENE SANITASI DENGAN KUALITAS BAKTERIOLOGIS DEPOT AIR MINUM (DAM) DI KABUPATEN BALANGAN Suriadi, Suriadi; Husaini, Husaini; Marlinae, Lenie
Jurnal Kesehatan Lingkungan Indonesia Vol 15, No 1 (2016): April 2016
Publisher : Master of Environmental Health Study Program, Faculry of Public Health, Faculty of Public

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (222.936 KB) | DOI: 10.14710/jkli.15.1.28-35

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Drinking water depo (DAM) continues to increase in line with the dynamics of the community needs to drinking water. DAM water contamination can be caused by  factor sanitation hygiene of the DAM. This research aims to determine of the relationshipbetweensanitary hygiene andbacteriological quality in the DAM. It is observational using cross sectional design. Thepopulation of this research was over all depo of drinking water in Balangan, while sample was takenby purposive sampling which has been determined based on inclusion and exclusion criteria. The research variables are location, building, production equipment, production process, sanitary facilities and bacteriological quality. The instrument used in this research was the observation sheets and laboratory tests. Data was analyzed by univariate, bivariate analysis using chi square test. The results showed from 41 DAM, there are 13 (31.7%)  less sanitary conditions of hygiene, 17 (41.5%) is enough and 11 (26.8%) good,  then  quality of bakteriologis are 30 (73%) eligible and 11 (27%)  not eligible. There is no relationship betwen locations (p = 0.698) and bacteriological quality, no relationship building (p=0.840) with the bacteriological quality, no relationship of production equipment (p=0.618) with the bacteriological quality, no relationship of production proces (p=0.986) with the bacteriological quality and there is no relationship of sanitation facilities (p=0.515) with bacteriological quality.The most of sanitation hygiene condition is notrelationshipto bacteriological quality of reffil drinking water depo. 
DIVIDEND POLICY IN DEVELOPED AND DEVELOPING COUNTRIES: A LITERATURE REVIEW Husaini, Husaini; Musnadi, Said; Faisal, Faisal
Proceedings of AICS - Social Sciences Vol 6 (2016): Proceeding of 6th AIC in conjuction with ICMSA
Publisher : Proceedings of AICS - Social Sciences

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This article aims to know the application of dividend policy in developing and developed countries. After reviewed 29 articles that located in ASIA and Europe and published by Elsevier and J-Stor publisher found the system of Common law is more dominant used in developed countries where the protection of the investors in stock market tends to be higher. Meanwhile, the system of Civil law tends to be applied by developing countries where the protection of the investors in the share market is relative low. Based the research results in some developed countries found that the application of the outcomes model related to dividend policy, although there exist different outcomes related to tax on dividends and profitability of the firms. While in developing countries, dividend policy is relatively lower that depends on the management of firms, and indicated the application of substitution model related to dividend policy.
FAKTOR PENYEBAB PENYAKIT AKIBAT KERJA PADA PEKERJA LAS Husaini, Husaini; Setyaningrum, Ratna; Saputra, Maman
Media Kesehatan Masyarakat Indonesia Vol 13, No 1: MARET 2017
Publisher : Faculty Of Public Health, Hasanuddin University, Makassar

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (245.55 KB) | DOI: 10.30597/mkmi.v13i1.1583

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Pengelasan merupakan tempat kerja yang berisiko tinggi menimbulkan gangguan kesehatan. Penelitian ini bertujuan mengidentifikasi dan menganalisis faktor yang berhubungan dengan Penyakit Akibat Kerja (PAK) pada pekerja las di Jalan A.Yani, Kota Banjarbaru. Desain penelitian adalah observasional analitik menggunakan metode cross sectional. Jumlah sampel berdasarkan quota sampling sebanyak 30 orang. Hasil menunjukkan tidak ada hubungan antara usia (p=0,513), masa kerja (p=0,729), lama kerja (p=0,337) terhadap PAK. Namun, adahubungan pengetahuan (p=0,046) dan penggunaan APD (p=0,000) terhadap PAK. Secara simultan usia, masa kerja, lama kerja, tingkat pengetahuan, dan penggunaan APD tidak berhubungan dengan kejadian PAK pada pekerja las. Secara parsial tingkat pengetahuan dan penggunaan APD hubungan parsial yang signifikan terhadap penyakit akibat kerja pada pekerja las. Tukang las yang memiliki tingkat pengetahuan yang kurang berisiko 5,442 kali lebih besar dibanding yang memiliki tingkat pengetahuan baik. Tukang las yang tidak menggunakan minimal empat APD utama berisiko 1,000 kali lebih besar dibanding yang menggunakan minimal empat APD utama. Tidak ada hubungan yang signifikan antara usia, masa kerja, dan lama kerja dengan penyakit akibat kerja. Ada hubungan antara tingkat pengetahuan dan penggunaan APD terhadap penyakit akibat kerja.
DECREASING THE HARDNESS Ca, Mg AND HEAVY METALS Fe, Mn, Zn IN RAW WATER WITH ZEOLITE FROM CIKALONG, TASIKMALAYA Husaini, Husaini; Soenara, Trisna
Jurnal Zeolit Indonesia Vol 5, No 1 (2006)
Publisher : Jurnal Zeolit Indonesia

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The decrease of hardness (Ca, Mg) and heavy metal (Fe, Mn, Zn) contents in raw water was conducted by flowing the sample water through the activated zeolite bed column. Treated water obtained from the experiment obviously met the parameter in standard requirement of drinking water. Activated natural zeolite from Cikalong, Tasikmalaya is able to decrease the content of Ca, Mg, Fe, and Mn in the sample water through the cation exchange process by percolation method with the optimum flow rate of 5 volume bed/hour on the zeolite with the particle size of -10+18 mesh especially for decreasing the hardness (Ca and Mg content). On the other hand, optimum condition for decreasing Fe and Mn contents are reached on the zeolite with the particle size of -10+18 mesh and water flow rate of 10 volume bed/hour. The final treated water contained 0,08 ppm Mn and 0,024 ppm Zn, meanwhile the hardness and other cations have been reduced below the required limit value (0,30 ppm for Fe, 0,10 ppm for Mn, and 0,05 ppm for Zn).
MODIFICATION OF NATURAL ZEOLITE FROM CIKALONG WEST JAVA WITH HEXADECIL TRIMETIL AMMONIA AND ABSORPTION RATE TEST OF SULPHATE AND CHROMATE IONS Husaini, Husaini; Soenara, Trisna
Jurnal Zeolit Indonesia Vol 2, No 1 (2003)
Publisher : Jurnal Zeolit Indonesia

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Cikalong mordenit natural zeolite with the average of cation exchange capacity (CEC) 154,2 meq/100 g has been used on modification trial. This modification attempts to increases the rate of anions absorbtion of zeolite in solution. On this research, zeolite is modificated using HDTMA through stirring process on beaker glass. Before the modification start, zeolite is set on pH 5 using sodium acetate solution. Variables on this research are: zeolite size (–10+18 mesh, -18+28 mesh, and –28+48 mesh), and HDTMA dosage (50%, 100%, and 200%). Furthermore modification of zeolite is tested it’s suphaate and chromate ions absorbtion rate. The modification of zeolite showed that the range of HDTMA weight percent that covers the surface of zeolite is 4,21 – 13,49% with the range of exchange ion capacity rate 137,05 – 143,00 meq/100 g. The best result of the absorbtion rate test is the -28 + 48 mesh zeolite with HDTMA dosage 200% for 49,46 mg/100g (5,15 mmol/kg) sulphate and for the cromat ion on -10 + 18 mesh zeolite with 50% HDTMA dosage, the absorbtion rate is 61,05 mg/100g (6,36 mmol/kg).
Co-Authors Abdul Karim Abdullah, Nirwal Mahdi Adenan Adenan, Adenan AMERALDO, FEDI Andrinaldo, Arisky Anisaturrahmi, Anisaturrahmi Aprianto, Ronal Arief Budiman Bachri, Achmad Alim Baekhaki, Khamid Bahrul Ilmi CAHYONO, STEFANUS S. Cahyono, Stefanus Suryo Christian, F. Yoppie Dahlia Dahlia Dessy Amalia, Dessy Dian Mutiasari, Dian Edhi, Sarwo Efriliana, Efriliana Eko Suhartono Erma Fajriah, Erma Fadian, Elyana Fahmi Fahmi Faisal Faisal Fatimah, Eldiana Happy Fitria, Happy Harliani, Siska Hasan, Muttaqin Hidayat, Kukuh Nur Huzaeni, Huzaeni Iskandar Zulkarnain Isma Coryanata Jamaludin Jamaludin johansyah johansyah Kishimoto, Kikuo Laila Rismawati, Laila Lailatul Fahriyah, Lailatul Laily Khairiyati Lenie Marlinae Lia Susvita Sari Makmun Makmun Maman Saputra, Maman Marnah Marnah Masimin Masimin Mursyidah Mursyidah Muta’alim Muta’alim, Muta’alim Nadia Eka Pratiwi, Nadia Eka Nasyuha, Wulan Fatin Noor Ahda Fadillah, Noor Ahda Noor Diani, Noor Nur Laily Paulina, Paula Permatasari, Winda Pratama, Andi Fitrawan Dwi Ratna Setyaningrum Retno Damayanti Ruslan Muhyi, Ruslan Said Musnadi Saiful Saiful Salahuddin Salahuddin Saputra, Jumadil Sariman Sariman Setia, Lisa Siti Nurjannah Suganal Suganal, Suganal Suriadi Suriadi Susanti, Melly Syabuddin Gade Syamsul Arifin TAHLI, LILI Tantawi, Rahmad Tatang Wahyudi, Tatang Trisna Soenara, Trisna Usman, Darman Wahyuddin Albra, Wahyuddin Widiarti, Astri Yuhelda Yuhelda, Yuhelda Yunita Ramanda, Yunita Yuniza, Salma Yuyun Wahyuni Zuhaimi Zuhaimi Zulfan Zulfan