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All Journal Jurnal Ilmu dan Teknologi Hasil Hutan Jurnal Teknik Sipil JURNAL SELULOSA Jurnal Ilmu dan Teknologi Kayu Tropis
Atmawi DARWIS
Sekolah Ilmu dan Teknologi Hayati Kampus ITB Jatinangor - Jawa Barat. 45363.
Agriculture, Biological Sciences & Forestry Civil Engineering, Building, Construction & Architecture Education

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Rasio Ikatan Pembuluh sebagai Substitusi Rasio Modulus Elastisitas pada Analisa Layer System pada Bilah Bambu dan Bambu Laminasi Bahtiar, Effendi Tri; Nugroho, Naresworo; Karlinasari, Lina; Darwis, Atmawi; Surjokusumo, Surjono
Jurnal Teknik Sipil Vol 21, No 2 (2014)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1007.219 KB)

Abstract

Abstrak. Anatomi bambu disusun oleh sel-sel yang heterogen. Komponen anatomi bambu yang memberikan sumbangan terbesar pada sifat mekanisnya adalah ikatan pembuluh, sehingga kerapatan ikatan pembuluh dapat digunakan sebagai variabel dasar untuk menganalisa sifat mekanis bambu. Kerapatan ikatan pembuluh bergradasi dari tepi hingga ke dalam bambu sehingga dapat diturunkan suatu fungsi linier ataupun non linier sebagai pendekatannya. Rasio modulus elastisitas (E) yang lazim digunakan pada metode transformed cross section, pada penelitian ini dicoba diganti dengan rasio ikatan pembuluh dengan asumsi bahwa keduanya adalah ekuivalen. Hasil penelitian memperlihatkan bahwa terdapat nilai korelasi Pearson yang tinggi antara hasil teoritis dan hasil empiris, sedangkan hasil uji t-student data berpasangan menunjukkan bahwa tidak ada perbedaan yang signifikan antara keduanya. Dengan demikian model transformasi yang diturunkan dapat digunakan untuk melakukan analisa layer system pada bilah bambu maupun bambu laminasi dengan hasil yang dapat dipertanggungjawabkan. Dari ketiga model transformasi terpilih (linier, logaritmik, dan power) model power adalah model yang terbaik karena menghasilkan nilai yang paling mendekati data empiriknya.Abstract. Bamboo anatomy is constructed from many types of cells. Vascular bundles are the cells which give the highest contribution to the bamboo strength, thus the density distribution of vascular bundles could be used as the main variable for analyzing the layer system of bamboo strip and laminated bamboo. The density of vascular bundles distribution degrade from outer to inner in a regular manner which could be fitted by linear and nonlinear function. Ratio of modulus of Elasticity (E) which widely used in transformed cross section method for analyzing the layered system was substituted by ratio of density distribution of vascular bundles within assumption that both are highly correlated. The data in this study proved that there was high Pearson’s correlation between the theoretical and empirical result, and the paired t-student test also showed both were not significantly different; thus the new method could be applied in very good result. There are three model applied in this study namely linear, logarithm, and power. Power model is the best among others since its theoretical results the nearest estimation to the empirical measurement.
Pendugaan Sisa Umur Pakai Kayu Komponen Cooling Tower di Pembangkit Listrik Tenaga Panas Bumi (PLTP) Unit II Kamojang Bahtiar, Effendi Tri; Nugroho, Naresworo; Arinana, Arinana; Darwis, Atmawi
Jurnal Teknik Sipil Vol 19, No 2 (2012)
Publisher : Institut Teknologi Bandung

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Abstract

Abstrak. Struktur cooling tower di PLTP (Pembangkit Listrik Tenaga Panas Bumi) Unit II Kamojang dibangun pada tahun 1988 dengan kayu sebagai komponen utamanya. Setelah 23 tahun umur pakainya, dirasa perlu dilakukan evaluasi sisa umur pakai sebagai salah satu bahan pertimbangan untuk memutuskan perobohan atau perpanjangan pemakaiannya. Evaluasi dilakukan melalui beberapa tahap yaitu: identifikasi jenis kayu dan keberadaan sisa bahan pengawet, pengukuran kedalaman kerusakan, pengujian sifat fisis mekanis, dan pemodelan matematis yang diturunkan dari uji creep dan pengurangan luas penampang kayu. Identifikasi memperlihatkan bahwa kayu yang dipergunakan untuk komponen utama cooling tower di PLTP Unit II Kamojang adalah redwood (Sequoia sempervirens) yang diawetkan dengan CCA (Chromated Copper Arsenat). Kerusakan telah terjadi sedalam 2,95 mm, namun secara umum masih memiliki tegangan ijin yang lebih tinggi daripada persyaratan NDS2005. Penelitian ini telah menghasilkan model terbaik yang dapat dipergunakan untuk menduga sisa masa pakai kayu komponen cooling tower di PLTP Unit II Kamojang dengan koefisien determinasi sebesar 86,84%. Abstract. Cooling tower in PLTP (Geothermal Power Plant) Unit II Kamojang was built in 1988, using solid wood as its main komponen. It is 23 years old nowadays, and should be evaluated to estimate its remaining lifetime. The evaluation conducted as scientific consideration for the company to decide wheter the cooling tower should be deconstruct or maintain to lenghten their lifetime. Some steps were conducted to estimate the remaining lifetime, namely: identification of wood species and the preservative remaining,measuring the depth of damages, measuring the physical and mechanical properties, and mathematical modelling which construct from creep testing and area reduction. This research show that the cooling tower was built with redwood (Sequoia sempervirens) which were treated with CCA (Chromated Copper Arsenat) preservative. The damage was happened until 2,95 mm depth, but the mechanical properties was commonly still better than NDS 2005 requirement. The  research result mathematical equation which is suitable to predict the remaining lifetime of wood component in PLTP Unit II Kamojang with coefficient of determination 86,84%.
The Characteristics of the Laminated Board of Oil Palm Trunk Darwis, Atmawi; Massijaya, Muhammad Y; Nugroho, Naresworo; Alamsyah, Eka M
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 12, No 2 (2014): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Jurnal Ilmu dan Teknologi Kayu Tropis

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (672.967 KB)

Abstract

The purpose of this study was to determine the physical and mechanical properties of glue laminated (glulam) of oil palm trunks lumber (OPTL) composed of different number of layers and trunk heights (2 m, 4 m, and 6 m). The number of layers was varied at 2, 3 and 4 layers with the thickness of lamina of 3 cm, 2 cm, and 1.5 cm, respectively. The results showed that the glulam of OPTL retained higher density and mechanical properties compared to those of its solid form. The properties of OPTL glulam decreased from the bottom to the top division of the trunk. The physical and mechanical properties of glulam increased with increasing layers. Modulus of Elasticity (MOE) of OPTL 4 layered glulam increased by more than 50% compared to that of its solid OPT. Isocyanate based adhesive used to produce the glulam resulted in a satisfied bonding indicated by 100% and 0% wood damage in shear and delamination test, respectively. The mechanical properties of OPTL glulam (MOE, MOR, and shear strength) failed to satisfy the requirement of Japan Agricultural Standard for Glued Laminated: No 1152 (2007).Keywords: glulam, laminae, oil palm trunk, physical-mechanical properties
Pangsor (Ficus callosa WILLD) and kecapi (Sandoricum kucape MERR) are usually planted in garden and rural forest. The objective of this study was to determine its specific gravity (SG), maximum crushing strength (σc//), longitudinal modulus elasticity (EL), and Poisson’s ratio (n).  The compression test  was conducted referring to  ASTM D143-94(2000) using UTM Instron 3369 which is equipped with two biaxial clip on extensometers.  The result showed that vertical and horizontal position of wood i Lusita WARDANI; Effendi Tri BAHTIAR; Ignasia Maria SULASTININGSIH; Atmawi DARWIS; Lina KARLINASARI; Naresworo NUGROHO; Surjono SURJOKUSUMO
Jurnal Ilmu dan Teknologi Hasil Hutan Vol. 4 No. 1 (2011): Jurnal Ilmu Teknologi Hasil Hutan
Publisher : Departemen Hasil Hutan, IPB

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Abstract

Pangsor (Ficus callosa WILLD) and kecapi (Sandoricum kucape MERR) are usually planted in garden and rural forest. The objective of this study was to determine its specific gravity (SG), maximum crushing strength (σc//), longitudinal modulus elasticity (EL), and Poisson’s ratio (n).  The compression test  was conducted referring to  ASTM D143-94(2000) using UTM Instron 3369 which is equipped with two biaxial clip on extensometers.  The result showed that vertical and horizontal position of wood in the trees statistically significant influenced on SG and σc//.  Horizontal position in Pangsor wood affected its EL, but the other position in both species were not significantly different.  There were poor correlations between SG with EL and σc//.   Poisson’s ratio value of both woods were in a range 0.0045 – 0.275 for longitudinal-radial direction (nLR), and 0.0151 – 0.1289 for longitudinal-tangensial direction (nLT).   Keywords :    Longitudinal Modulus of Elasticity, Maximum Crushing Strength, Poisson’s Ratio, Pangsor wood, Kecapi wood
Pendugaan Sisa Umur Pakai Kayu Komponen Cooling Tower di Pembangkit Listrik Tenaga Panas Bumi (PLTP) Unit II Kamojang Effendi Tri Bahtiar; Naresworo Nugroho; Arinana Arinana; Atmawi Darwis
Jurnal Teknik Sipil Vol 19 No 2 (2012)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/jts.2012.19.2.2

Abstract

Abstrak. Struktur cooling tower di PLTP (Pembangkit Listrik Tenaga Panas Bumi) Unit II Kamojang dibangun pada tahun 1988 dengan kayu sebagai komponen utamanya. Setelah 23 tahun umur pakainya, dirasa perlu dilakukan evaluasi sisa umur pakai sebagai salah satu bahan pertimbangan untuk memutuskan perobohan atau perpanjangan pemakaiannya. Evaluasi dilakukan melalui beberapa tahap yaitu: identifikasi jenis kayu dan keberadaan sisa bahan pengawet, pengukuran kedalaman kerusakan, pengujian sifat fisis mekanis, dan pemodelan matematis yang diturunkan dari uji creep dan pengurangan luas penampang kayu. Identifikasi memperlihatkan bahwa kayu yang dipergunakan untuk komponen utama cooling tower di PLTP Unit II Kamojang adalah redwood (Sequoia sempervirens) yang diawetkan dengan CCA (Chromated Copper Arsenat). Kerusakan telah terjadi sedalam 2,95 mm, namun secara umum masih memiliki tegangan ijin yang lebih tinggi daripada persyaratan NDS2005. Penelitian ini telah menghasilkan model terbaik yang dapat dipergunakan untuk menduga sisa masa pakai kayu komponen cooling tower di PLTP Unit II Kamojang dengan koefisien determinasi sebesar 86,84%. Abstract. Cooling tower in PLTP (Geothermal Power Plant) Unit II Kamojang was built in 1988, using solid wood as its main komponen. It is 23 years old nowadays, and should be evaluated to estimate its remaining lifetime. The evaluation conducted as scientific consideration for the company to decide wheter the cooling tower should be deconstruct or maintain to lenghten their lifetime. Some steps were conducted to estimate the remaining lifetime, namely: identification of wood species and the preservative remaining,measuring the depth of damages, measuring the physical and mechanical properties, and mathematical modelling which construct from creep testing and area reduction. This research show that the cooling tower was built with redwood (Sequoia sempervirens) which were treated with CCA (Chromated Copper Arsenat) preservative. The damage was happened until 2,95 mm depth, but the mechanical properties was commonly still better than NDS 2005 requirement. The  research result mathematical equation which is suitable to predict the remaining lifetime of wood component in PLTP Unit II Kamojang with coefficient of determination 86,84%.
Rasio Ikatan Pembuluh sebagai Substitusi Rasio Modulus Elastisitas pada Analisa Layer System pada Bilah Bambu dan Bambu Laminasi Effendi Tri Bahtiar; Naresworo Nugroho; Lina Karlinasari; Atmawi Darwis; Surjono Surjokusumo
Jurnal Teknik Sipil Vol 21 No 2 (2014)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.5614/jts.2014.21.2.6

Abstract

Abstrak. Anatomi bambu disusun oleh sel-sel yang heterogen. Komponen anatomi bambu yang memberikan sumbangan terbesar pada sifat mekanisnya adalah ikatan pembuluh, sehingga kerapatan ikatan pembuluh dapat digunakan sebagai variabel dasar untuk menganalisa sifat mekanis bambu. Kerapatan ikatan pembuluh bergradasi dari tepi hingga ke dalam bambu sehingga dapat diturunkan suatu fungsi linier ataupun non linier sebagai pendekatannya. Rasio modulus elastisitas (E) yang lazim digunakan pada metode transformed cross section, pada penelitian ini dicoba diganti dengan rasio ikatan pembuluh dengan asumsi bahwa keduanya adalah ekuivalen. Hasil penelitian memperlihatkan bahwa terdapat nilai korelasi Pearson yang tinggi antara hasil teoritis dan hasil empiris, sedangkan hasil uji t-student data berpasangan menunjukkan bahwa tidak ada perbedaan yang signifikan antara keduanya. Dengan demikian model transformasi yang diturunkan dapat digunakan untuk melakukan analisa layer system pada bilah bambu maupun bambu laminasi dengan hasil yang dapat dipertanggungjawabkan. Dari ketiga model transformasi terpilih (linier, logaritmik, dan power) model power adalah model yang terbaik karena menghasilkan nilai yang paling mendekati data empiriknya.Abstract. Bamboo anatomy is constructed from many types of cells. Vascular bundles are the cells which give the highest contribution to the bamboo strength, thus the density distribution of vascular bundles could be used as the main variable for analyzing the layer system of bamboo strip and laminated bamboo. The density of vascular bundles distribution degrade from outer to inner in a regular manner which could be fitted by linear and nonlinear function. Ratio of modulus of Elasticity (E) which widely used in transformed cross section method for analyzing the layered system was substituted by ratio of density distribution of vascular bundles within assumption that both are highly correlated. The data in this study proved that there was high Pearson's correlation between the theoretical and empirical result, and the paired t-student test also showed both were not significantly different; thus the new method could be applied in very good result. There are three model applied in this study namely linear, logarithm, and power. Power model is the best among others since its theoretical results the nearest estimation to the empirical measurement.
Bond Ability of Oil Palm Xylem with Isocyanate Adhesive Atmawi Darwis; Muhammad Y Massijaya; Naresworo Nugroho; Eka M Alamsyah; Dodik R Nurrochmat
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 12, No 1 (2014): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Masyarakat Peneliti Kayu Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (492.796 KB) | DOI: 10.51850/jitkt.v12i1.81

Abstract

Oil palm xylem composed of vascular bundles and parenchyma tissue and directly related to its properties. Utilization of oil palm xylem into the wood laminate products requires information on its bond ability to adhesive used. Isocyanate adhesive is a prospective adhesive due to its various advantages compared to other adhesives. This study aimed to obtain information about the bond ability of the oil palm xylem with isocyanate adhesive. The results showed that isocyanate adhesive has good wettability on oil palm xylem indicated by its contact angle of below 90°. Isocyanate adhesive also showed good performance by looking at the value of wood failure and delamination. However, the shear strength of laminated oil palm xylem was low. Wood failure occurred in the parenchymal tissues region.Key words: bond ability, isocyanates, laminated board, oil palm xylem
Presentase Kayu Teras dan Kayu Gubal serta Penentuan Kayu Juvenil dan Kayu Dewasa pada Lima Kelas Umur Jati (Tectona grandis L.f.) The Percentage of Heartwood and Sapwood and Determination of Juvenile and Mature Wood on Five Age-Class of Teak (Tectona grandis L.f.) Atmawi Darwis; Rudi Hartono; Sansan Sarif Hidayat
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 3, No 1 (2005): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Masyarakat Peneliti Kayu Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (169.273 KB) | DOI: 10.51850/jitkt.v3i1.298

Abstract

Teak wood is one of fancy woods with durability class I ~ II and strength class II and has very beautiful decorative value. The existence of heartwood has more value than sapwood, because of the color and its high natural durability. The high proportion of Teak heartwood will increase higher benefit and sale value (economic value). The existence of juvenile wood is generally less liked then mature wood because of its characteristics. However, determining juvenile wood is not as easy as determining heartwood from sapwood. One of the methods is to see the variation of fiber length from pith to bark.The purposes of this research were to find out the percentage of heartwood and sapwood and also to know the time when juvenile wood becoming mature wood on five age-class of Teak (I ~ V).The research results showed that during the increasing of teak age-class, the percentage of heartwood was also growing and on the contrary, the percentage of sapwood was decreasing. During the process of determining juvenile wood from mature wood, the result proved that on teak wood with the age-class I ~ II, the fiber length showed increment so that the process of forming into mature wood was not yet to be seen. While teak with the age-class III ~ V showed that the form of mature wood started to show up after the 11th or 12th annual increment
Anatomical Structure of Surian Wood (Toona sinensis Roem) Atmawi Darwis; Imam Wahyudi; Ratih Damayanti
Jurnal Ilmu dan Teknologi Kayu Tropis Vol 10, No 2 (2012): Jurnal Ilmu dan Teknologi Kayu Tropis
Publisher : Masyarakat Peneliti Kayu Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (741.045 KB) | DOI: 10.51850/jitkt.v10i2.115

Abstract

Surian wood (Toona sinensis Roem) is one species of wood that is easily found in Indonesia, especially in West Java. The purpose of this study was to descriptively and quantitatively observe the anatomical structure of surian wood. The wood was collected from Sumedang regency, West Java. The results showed that this wood had oval to round shaped vessels and some of them contain a reddish brown liquid that causes a characteristic odor due to axial intersellular canals. The vessels were mostly solitary and arranged to follow the pattern of the porous ring. There were septate fibers indicated. Axial parenchyma cells were included in the category of paratracheal vasisentrik and marginal bands in the early wood. The ray composition consists of upright and procumbent cells. In the ray cell, there are prismatic crystals in rhomboidal or octahedral shape. Based on the dimensions of fibers, this wood has first-class fiber quality for pulp and paper.Key words: anatomical structure, fiber dimension, fiber quality, Toona sinensis
Ketahanan Batang Kelapa Sawit Diimpregnasi Resin Pinus dan Serbuk Kayu Surian Terhadap Rayap dan Cuaca Jessica Gita Adjani; Anne Hadiyane; Tati Karliati; Atmawi Darwis; Viona Febrinisa Mukhsin
JURNAL SELULOSA Vol 11, No 02 (2021): JURNAL SELULOSA
Publisher : Center for Pulp and Paper

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25269/jsel.v11i02.333

Abstract

The Resistance of Pine Resin and Surian Wood Sawdust Impregnated Oil Palm Stem Against Termite and WeatheringAbstractImpregnation substances into the oil palm trunks are one way to improve the oil palm trunk quality. This paper studies the optimum formulation of oil palm trunk impregnanted pine resin and Surian sawdust against dry-wood and subterranean termites as well as weathering performance. Impregnant concentration variations were mixtures of Tusam resin and Surian wood sawdust of 0% (RS0), 4% (RS1), 6% (RS2), and 8% (RS3) with three replications. Dry-wood termite test, subterranean termite test, and weather resistance test were carried out for 12 weeks of observation. The results showed that RS3 treatments were the optimum formulation of impregnated material used for oil palm trunk based on its resistance against dry-wood and subterranean termites resistance, while RS0 treatments were the optimum formula for weathering performances.Keywords: impregnation, oil palm trunk, pine resin, sawdust, Surian woodAbstrakSalah satu upaya untuk meningkatkan kualitas batang kelapa sawit adalah melalui impregnasi dengan resin pinus dan serbuk kayu Surian. Penelitian ini bertujuan untuk menentukan formulasi optimum impregnan batang kelapa sawit terhadap serangan rayap kayu kering dan rayap tanah serta ketahanan terhadap cuaca. Variasi konsentrasi impregnan yang digunakan yaitu campuran resin pinus dan serbuk kayu Surian 0% (RS0), 4% (RS1), 6% (RS2), dan 8% (RS3). Uji ketahanan rayap kayu kering, uji rayap tanah, dan uji ketahanan terhadap cuaca dilakukan selama 12 minggu pengamatan. Hasil penelitian menunjukkan bahwa konsentrasi optimum bahan impregnan batang kelapa sawit terimpregnasi terhadap ketahanan rayap kayu kering dan rayap tanah adalah formula RS3, sedangkan formulasi impregnan ketahanan cuaca optimum adalah batang kelapa sawit dengan formula RS0.Kata kunci: impregnasi, batang kelapa sawit, resin pinus, serbuk kayu, kayu Surian 
Co-Authors Alamsyah, Eka M Anne Hadiyane ARINANA . Dodik R Nurrochmat Effendi Tri Bahtiar Eka M Alamsyah Ignasia Maria SULASTININGSIH Imam Wahyudi Indrawan, Imam Wahyudi Jessica Gita Adjani Karliati, Tati Lina Karlinasari Lusita WARDANI Massijaya, Muhammad Y Muhammad Y Massijaya Naresworo Nugroho Ratih Damayanti Rudi Hartono Sansan Sarif Hidayat Surjono Surjokusumo Surjono Surjokusumo Surjono Surjokusumo Viona Febrinisa Mukhsin