NUGROHO, Naresworo, Indonesia

  • Jurnal Ilmu dan Teknologi Hasil Hutan Vol. 3 No. 1 (2010): Jurnal Ilmu Teknologi Hasil Hutan - Articles

    Connection is the weakest point of the structural building system. Structural construction building system must ensure that there is only a tensile force or just axial compression that is working on the connection. Data on the lateral design values (Z) double shear connection wood beam with nails of steel side plates for various types of tropical Indonesian wood have not studied much. Average moisture content (MC) for the main member varies from 13.3 to 22.5% while average specific gravity (r) from 0.27 to 0.76 and then wood density from 0.31 to 0.89 g/cm3. From this average value of MC, SG and wood density the lowest is sengon and the highest is rasamala wood. Average allowable load of compression parallel to grain ( ) and parallel tensile ( )is sengon, but the highest is bangkirai. There is a general tendency that and is linier to r of those wood. is approximately 2 times greater than its .  The number of nail (4-10 pieces) did not give effect of average Z, but with the nail diameter 4.1 to 5.2 mm Z increased significantly and this value decreased on 5.5 mm diameter nail. Average Z also increases with increasing of ρ for  displacement 1.50 mm (Indonesian Standard PKKI NI-5 1961)) and 5.0 mm (breaking load). The increasing of Z happens because ρ effect. At 5.0 mm displacement the increase of Z is not as sharp as that of 1.5 mm. Power regression type is the best equation to predict Z of wood density for several diameters of nails.

     

    Keywords :    Allowable load of tensile parallel to grain, density, displacement, double shear connection, lateral design values


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  • Jurnal Ilmu dan Teknologi Hasil Hutan Vol. 1 No. 2 (2008): Jurnal Ilmu Teknologi Hasil Hutan - Articles

    The research objectives are to evaluate physical and mechanical properties of OSB based on strand orientations made from akasia wood (Acacia mangium Wild) and afrika wood (Maesopsis eminii Engl). Akasia and afrika wood are used for OSB strand material with phenol formaldehyde (PF) as adhesives and addition of paraffin. OSB made in this research consists of three plies whereas are differed into eight strand orientations.  Hot press was carried out at 160ºC and pressure 25 kg/cm² for 15 minutes. Determination of OSB physical and mechanical properties referred to JIS A 5908-2003. Result showed that strand orientations have not affected to OSB physical properties except for linear swelling 24 h, but it significantly influences all mechanical properties of OSB. Wood species has an effect on mechanical properties of OSB in the dry test, wet MOE lengthwise test and OSB physical properties, particularly to OSB density and water absorbing capability at 2 h and 24 h.  All of OSB physical properties are meet JIS A 5908-2003 standard, but not all of the mechanical properties such as dry MOE lengthwise, dry MOE and MOR widthwise. The best physical and mechanical properties is presented by OSB made from akasia wood in strand orientation F (core layer is orientated and surface layers are in random, R°/0°/R°), G (core layer is orientated 45° and surface layers are in random, R°/45°/R°), B (surface strand direction is upright to core strand direction, 0°/90º/0°), and C (core layer is in random, surface layers are orientated, 0°/R/0°) whereas all parameters meet JIS A 5908-2003 standard. In comparation with strand orientation B that is frequent used in industry, strand orientation F and G are proficient to raise the modulus elasticity value (MOE) and strength (MOR) as much as 167.8-231.7% and 89.7-109.9%, respectively; especially in widthwise board application. Furthermore, strand orientation F and G are more flexible as structural components.

    Keywords:   Oriented strand board, strand orientation, phenol formaldehyde


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  • Jurnal Ilmu dan Teknologi Hasil Hutan Vol. 1 No. 1 (2008): Jurnal Ilmu Teknologi Hasil Hutan - Articles

    Glued-laminated (glulam) beams is one of engineered wood products used for structural applications.  The objective of this research is to evaluate characteristics of glulam beams made from Acacia mangium Willd.    Laminations used were 2, 4, 6, 8 and 12 cm in widthnesses, 2 cm in thickness and 260 cm in length.  Each lamination was graded using Machine Stress Grading (namely by Panter or plank sorter) to determine the modulus of elasticity (MOE) value.  The glulam beams was 6 cm x 12 cm in five types of cross-section which arranged by various widths and those MOE of laminations.  Glulam beams were bonded by water based polymer isocyanate (WBPI) using 280 g/m2 double glue spread.  The research results showed that glulam beams made from A. mangium Willd.  fulfilled the JAS 234:2003 standard as on following properties: moisture content, MOE, MOR, shear strength and immersion delamination test.  However, performance of glulam was unsatisfactory in wood failure ratio and boiling water soak delamination test.

     

    Keywords:  Glulam beam, MOE, MOR, shear strength, delamination


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  • Jurnal Ilmu dan Teknologi Hasil Hutan Vol. 1 No. 1 (2008): Jurnal Ilmu Teknologi Hasil Hutan - Articles
    The objective of this research is to evaluate the characteristic of  composite board made from coconut fibre, recycled polypropylene (RPP), and bamboo matting layers. The board samples target density was 0,70 g/cm3. The board construction type was core type composite board (three layers).  Coconut fiber and RPP were used as core, and bamboo matting was used as face and back layers. RPP was used 50% based on coconut fiber oven dry weight. The bamboo sheet wide is 1 cm and 2 cm, with and without bark. The bamboo matting layers were used in slope (45˚) and perpendicular (0/90˚) orientation to length of the board. The research results showed that utilization of bamboo matting layers increase the mechanical properties of board. All of composite board made from coir, RPP, and bamboo matting layers fulfill  the JIS A 5908 standard in density, thickness swelling after 24 hours of water immersions, and screw holding power. Only composite boards with bamboo matting layers with bark, sheet wide 1 cm, and perpendicular orientation to length of the board fulfill JIS A 5908 1994 standard for veneered particleboard in MOE.  However, application of bamboo matting layers without bark is adviced better because more efficient in the raw material using.   Keywords:               Composites board, coconut fiber, recycled polyprophylene, bamboo matting layers
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  • Jurnal Ilmu dan Teknologi Hasil Hutan Vol. 4 No. 1 (2011): Jurnal Ilmu Teknologi Hasil Hutan - Articles

    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


    Abstract  PDF