• Journal of the Korean Wood Science and Technology
• /
• v.22 no.3
• /
• pp.17-25
• /
• 1994

This study was carried out to compare the properties of Com-Ply Boards with those of OSBs. These two kinds of boards were made of same flakes. Com-Ply Boards were covered with three different thickness veneers, such as 4mm, 3mm, and 2.5mm. All manufactured Com-Ply Boards and OSBs were 12mm thick. In MOR, all Com-Ply Boards were higher than OSB, and especially 3mm-veneer and 2.5mm-veneer Com-Ply Board were highest. But OSB showed 420kg/$cm^2$. 3mm-veneer Com-Ply Board showed the highest internal bonding 7.0kg/$cm^2$ and then 2.5mm-veneer showed 6.8kg/$cm^2$, and OSB showed 6.6kg/$cm^2$. Screw holding strength showed the high value 23.9kg/$cm^2$, 25.5kg/$cm^2$, and 29.3kg/$cm^2$ respectively at 3mm-veneer, 2.5mm-veneer Com-Ply Board and OSB. Thickness swelling of Com-Ply Boards was lower than that of OSB, but Water absorption of OSB was lower. Finally it was very encouraging that all properties of OSB without veneer, whose cost is higher than flake and whose properties is better, were not worse than those of Com-Ply Board with veneer. It seems That more researches on OSB will be required.

• Journal of the Korean Wood Science and Technology
• /
• v.40 no.4
• /
• pp.287-293
• /
• 2012

This study was carried out in order to compare nail shear strength between domestic plywood and imported OSB for structural sheathing members as infill wall of wooden construction. The differences of nail shear strength between parallel-to-grain direction and perpendicular-to-grain direction of sheathing material to frame material were distinct at the plywood composition. The shear strengths of plywood and OSB with nail met current design values. The plywood of P-4 type, which uses MLH at surface layer and constructs 7 ply, showed greater than OSB regardless of grain direction of sheathing material to frame material. When the plywood as sheathing material to frame material was used, it was found out that the overall construction of perpendicular-to-grain direction of plywood had greater nail shear strengths than the construction of parallel-to-grain.

• Journal of the Korean Wood Science and Technology
• /
• v.42 no.2
• /
• pp.163-171
• /
• 2014

Environmental issues about indoor air quality have been increased and focused on volatile organic compounds (VOCs) caused cancer, asthma, and skin disease. Reducing VOCs has been attempted in many different methods such as using environmentally friendly materials and air cleaner or purifier. Charcoal is well known material for absorbing VOCs. Therefore, carbonized board from medium density fiberboard has been developed. We assumed that the source of carbonized boards can be any type of wood-based panels. In this study, carbonized boards were manufactured from oriented strand board (OSB) at 400, 600, 800, and $1000^{\circ}C$. Each carbonized OSB (c-OSB) was evaluated and determined physiomechanical characteristics such as exterior defects, dimensional shrinkage, modulus of elasticity, and bending strength. No external defects were observed on c-OSBs at all carbonizing conditions. As carbonizing temperature increased, less porosity between carbonized wood fibers was observed by SEM analysis. The higher rate of dimensional shrinkage was observed on c-OSB at $1000^{\circ}C$ (66%) than c-OSB at 400, 600, and $800^{\circ}C$ (47%, 58%, and 63%, respectively). The densities of c-OSBs were lower than original OSB, but there was no significant different among the c-OSBs. The bending strength of c-OSB increased 1.58 MPa (c-OSB at $400^{\circ}C$) to 8.03 MPa (c-OSB at $1000^{\circ}C$) as carbonization temperature increased. Carbonization temperature above $800^{\circ}C$ yielded higher bonding strength than that of gypsum board (4.6 MPa). In conclusion, c-OSB may be used in sealing and wall for decorating purpose without additional artwork compare to c-MDF which has smooth surface.

• Journal of the Korean Wood Science and Technology
• /
• v.36 no.2
• /
• pp.56-62
• /
• 2008

The surface and edge structure of OSB is defined by surface strand orientation and strand mat thickness variation parallel to the length of the panel using video-microscope. The bending strength of OSB was correlated with surface strand orientation and decreased with increasing the orientation angle in the direction parallel to length of the panel. Average strand mat thickness variation parallel to the length of the panel did not influence the bending strength, but the bonding characteristics among the outermost strands affects the bending strength of OSB. Hankinson formula can be used to predicts the MOE according to strand orientation in the surface of OSB, and more precise strand alignment and reducing thickness variation should be important in the structural performance of OSB panels.

• Journal of Korea Port Economic Association
• /
• v.32 no.4
• /
• pp.57-71
• /
• 2016

The development of ocean industries is an existing and important problem for South Korea, which is mostly surrounded by sea and has a long coastline along three seas. It is necessary for researchers to make efforts to enhance its cost and time competitiveness, because many ocean-based activities have been carried out in harsh physical conditions when compared with land-based ones. One of these efforts to improve efficiency is to operate an Offshore Supply Base (OSB), which is a basic infrastructure required to develop ocean industries effectively. For this reason, the construction and operation of OSBs have become an issue in Korea. The relevant research is limited. Nevertheless, there are a few reports published by Korean research institution. They focus on promoting ocean industries and only mention the necessity of OSB as a promotion tool for the industries. This study on the other hand, addresses various issues on the construction of OSBs in Korea and suggests implications for them. To examine the conditions on the construction of OSBs in Korea, we conduct case studies of Houston and Singapore, the representative regions where a massive OSB has been constructed and operated. In addition, we use Analytic Hierarchy Process (AHP) to evaluate the relative priorities of the services provided by OSBs if constructed in Korea.

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.5
• /
• pp.46-57
• /
• 2007

The leachability of boron in zinc borate (ZB)-modified oriented strandboard (OSB) from southern wood species was investigated in this study. The leaching experiments were conducted by exposing edge-sealed OSB samples under running water at $31^{\circ}C$ for 8, 24, 72, and 216 h. The results from leached samples were compared with those from the unleached controls. Boron leaching of the modified OSB occurred upon the initial water exposure, and the leaching rate decreased as the leaching time increased. Initial boric acid equivalent (BAE) level, wood species, and sample thickness swelling significantly influenced the leachability. There was no consistent effect of polyethylene glycol (PEG) on zinc borate leaching. The glue-line washing within OSB due to thickness swelling of the test samples under water and decomposition of the borate to form water-soluble boric acid were thought to be two possible causes for the observed leaching. The relationship between assayed BAE and leaching time followed a decaying exponential function for zinc borate treated OSB. From the boron/zinc ratio after each leaching period, boron element in ZB was more or less leachable. The material constant of the regression models allowed comparing the leachability of the modified OSB for various wood species. An unified leaching method for treated wood composite materials is needed.

• Journal of the Korea Furniture Society
• /
• v.10 no.2
• /
• pp.1-8
• /
• 1999

The use of structural wood based panels like plywood, OSB in many applications involves the use of nails, and data on the performance of panel-nail connection are needed for design and comparative purpose. This study was carried out to develop basic information on nail performance(withdrawal, embedding, nailhead push through) with water absorption in plywood and OSB. In withdrawal resistance test, initial stiffness of plywood performed better than OSB in 24hr soaked condition. The soaked condition reduced average nail withdrawal resistance value about 46% (12d mail), 53%(8d nail) in OSB, 17%(12d mail), 24%(8d mail) in plywood. The nail embedding strength of plywood also performed better than that of OSB and retention value(wet strength/dry strength) yielded similar in each nail types. The nail head push through capacity of OSB was higher than that of plywood in dry condition, but equal or lower in soaked condition. Therefore, critical consideration about structural panels is required in moist applications. The average values of nail withdrawal, nail embedding strength and nail head push through resistance of tested materials meet the minimum requirement of various specification and standards.

• Journal of the Korean Wood Science and Technology
• /
• v.37 no.2
• /
• pp.121-127
• /
• 2009

Acacia wood (Acacia mangium Willd.) is the most popular fast growing tree species planted in timber estate in Indonesia and is considered to be very valuable raw materials for structural composite products. The objective of the research was to evaluate the properties of OSB prepared from A. Mangium wood with or without immersing the strands to hot water at $80^{\circ}C$ for 2 hours. MDI adhesive was used in 3 levels i.e., 3%, 5%, and 7%. The moisture content of strand was 7%. The results indicated that immersing strands in hot water for 2 hours at $80^{\circ}C$ prior to manufacture OSB improved significantly the mechanical peoperties (i.e., MOR and MOE) of OSB. The higher the adhesive content resulted in the better the dimensional stabilisation (i.e., water absorption and thickness swelling) and the mechanical properties (i.e., MOR, MOE and IB) of OSB. OSB prepared from hot-water immersed strands with 5% adhesive content has met all parameters requirement on the JIS A 5908 (2003) standard.

• Fire Science and Engineering
• /
• v.30 no.6
• /
• pp.57-63
• /
• 2016

In this study, the toxicity of combustion products of wood-based materials (MDF, OSB) were analyzed using experimental animal techniques. The average deed stopping time of MDF was shorter than that of OSB. This means that the toxicity of the combustion products of MDF is higher than that of OSB. To analyze the cause of the result quantitatively, Fourier transform infrared spectroscopy (FT-IR) of the gas phase materials was performed. Qualitative analysis result, CO and $CO_2$ were detected. Quantitative analysis results, the gas generation rate was higher in OSB than in MDF. Blood analysis of mice revealed, COHb to be higher in OSB than MDF. A correlation between the gas generation rate and COHb was found. Currently, the toxicity of the combustion products of the materials is being examined using the toxicity index, such as Fractional Effective Dose (FED). The FED is based on the gas emissions. The average deed stopping time decreased with increasing toxicity of exposed material. On the other hand, the result of this study showed that, the CO emissions of OBS were 186.5% that of MDF. The COHb of OSB was > 129.6% that of MDF. Nevertheless, the average deed stopping time of the OSB is 51 seconds longer than that of MDF. Therefore, more toxicity studies on factors other than the gas phase materials in the combustion products will be needed.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.160-160
• /
• 2017

Drought stress is a major constraint of crop development and productivity. Plants have evolutionally developed several mechanisms at the molecular, cellular, and physiological levels to overcome drought stress. The basic Leucine zipper (bZIP) transcription factor (TF) family members are starting to be concerned about their roles in drought stress responses. In this study, we functionally characterized OsbZIP66, a rice group-E bZIP TF, to be associated with rice drought tolerance mechanisms. Expression of OsbZIP66 was significantly induced upon treatments of rice plants with drought, high salinity, and ABA. These observations and the fact that the OsbZIP66 promoter contains ten ABA-responsive elements suggest that OsbZIP66 is up-regulated by drought stress in an ABA-dependent manner. Overexpression of both OsbZIP66 in a whole plant body and specifically in roots enhanced drought tolerance of rice plants, indicating that the rice drought tolerance positively correlates with the expression levels of OsbZIP66. Thus, our results demonstrated that OsbZIP66 has a potential for use in biotechnological development of high-yielding rice plants under drought conditions.