Abstract

Global competition is increasingly impacting business organization and practice, which is forcing US hardwood manufacturers to become more efficient in manufacturing, distribution, and marketing. At the international marketing level, firms must target their promotional mix more effectively and efficiently toward relevant buyers from around the world. International trade shows have long been considered a cost-efficient and quick way to promote exports or gain valuable market information for entry. China is now the world's largest furniture producer and exporter and the leading importer of US hardwoods. As such, it is important to better understand mechanisms for cost-effective participation in this huge hardwood market. This study was conducted to increase awareness of the importance of US–Chinese hardwood trade and knowledge of Chinese international furniture supply trade shows (IFS-TSs). In 2011, US hardwood lumber exports to China totaled US$506 million or two-thirds of the US$775 million worth of all hardwood product exports that year. A total of 27 Chinese IFS-TSs were identified through a two-part process: a review of secondary sources and personal communication with key trade show informants in China. This article also profiles the largest and most influential Chinese IFS-TSs (n = 9) in terms of the number of attendees and exhibitors, and other relevant factors. A better understanding of these trade shows will help US hardwood manufactures make show participation decisions.

Abstract

The stocks and flows of six major structural wood products (SWPs)—lumber, plywood, oriented strand board [OSB], glue laminated timber, I-joists, and laminated veneer lumber (LVL)—in US single family homes were modeled from 1950 to 2010. The consumption of these products in US single family homes and their emissions as construction and demolition wastes were estimated. The net consumption of SWPs decreased from 119 kg/m² constructed in 1986 to 82 kg/m² in 2010. Softwood lumber was consistently the predominant SWP, but its usage intensity decreased from 95 kg/m² in 1986 to 52 kg/m² in 2010. Since the 1980s, modern SWPs, such as I-joists, LVL, and OSB, have replaced lumber and plywood products. The needs of the US single family housing industry have been met by a smaller mass of SWPs per unit area constructed.

The mass of SWP present in construction wastes was influenced strongly by building cycles. Production of construction waste peaked in 2005, when 3.31 million tonnes of SWPs were produced by 1.72 million single family housing starts. It diminished to 0.874 million tonnes of SWPs as the housing starts fell to 445,000 in 2009. In contrast, the mass of demolition wastes produced was affected substantially by the number of houses in the stock and their half-lives. Approximately 4.5 million tonnes of SWP demolition waste were produced in 2010, and in the same year, the stock of SWPs in US single family homes reached 1,220 million tonnes.

Abstract

This study evaluated the wood properties of 5- and 7-year-old Acacia mangium trees planted in West Java, Indonesia. A plot (20 by 20 m) was selected in each stand. The stem diameter and stress-wave velocity (SWV) were measured for all trees (n = 24 and 18 for 5- and 7-y-old trees, respectively) in the plots. Core samples were taken from all trees in each plot using an increment borer to measure the basic density (BD) and compressive strength parallel to the grain (CS). The mean ± standard deviation stem diameter was 13.1 ± 3.0 and 21.9 ± 3.8 cm in 5- and 7-year-old trees, respectively. There was no significant correlation between stem diameter and SWV. The mean BD and CS for 5-year-old trees were 0.42 ± 0.02 g cm⁻³ and 30.0 ± 4.4 MPa, respectively, and for 7-year-old trees were 0.45 ± 0.02 g cm⁻³ and 32.8 ± 3.6 MPa, respectively. There was a positive correlation between BD and CS in 5- and 7-year-old trees (r = 0.790 and 0.583, respectively). The radial variation patterns for BD and CS were similar in 5- and 7-year-old trees: BD and CS gradually increased to about 6 cm from the pith, after which it was almost constant toward the bark. The results suggest that xylem maturation depends on the growth diameter in A. mangium.

Abstract

A common problem with finger-jointed wooden furniture components is chipping in the finger joints due to fiber deviations around sound knots. To avoid this, a fixed size safety zone between defects and crosscuts is used, but can lead to an excess of material cut away in the crosscutting operation.

To reduce chippings in finger joints while maximizing recovery, an adaptive strategy was developed for setting the safety zone size between sound knots and finger joints in Scots pine (Pinus sylvestris L.) furniture components. The strategy was based upon modeling the risk of chipping the finger joint depending on the knot measurement. The model was used in an adaptive strategy in order to minimize the expected loss due to cutting away material around knots, compared with the cost of rejecting components in later stages due to chipped finger joints. Thus, each knot was assigned a unique safety zone. The strategy was tested using computer simulation of the finger-jointing process, and a sensitivity analysis was performed in order to quantify the effect of variations in the input data. The results show that the adaptive strategy improves recovery by at least 3 percent in the process of turning lumber into finger-jointed furniture components. It is very robust toward variations in knot size measurements (e.g., by scanning equipment), but less robust toward variations in crosscutting precision.

Abstract

The Civil Engineering Department of the University of Coimbra set up a project with the purpose of grading and characterizing Portuguese maritime pine utility poles. To achieve the aim of this project, 64 utility poles that met the requirements of Comité Européen de normalization EN14229 were collected in the central coastal region of Portugal. The utility poles were characterized according to various anatomic and geometric characteristics: the number of knots, the amount of taper, the nominal diameter, and the rate of growth. Each utility pole was also tested in bending. From these tests, the bending strength and modulus of elasticity were determined. The results obtained were in line with previously published results for utility poles from other species. In addition to this, wood samples were collected from each specimen to determine the moisture content and density. The correlation coefficients between the bending strength and modulus of elasticity were determined, as were the coefficients between the bending strength and the anatomic and geometric characteristics. From this analysis, it was concluded that the properties that had a closer correlation with bending strength were those of modulus of elasticity, density, and taper. The correlation coefficient between bending strength and the set of geometric and anatomic characteristics and density was determined by a multiple linear regression, and it was concluded that this set of parameters may be used for nondestructive evaluation of the utility poles.

Abstract

The effect of metal end plates on reducing checking of pentachlorophenol-treated Douglas-fir crossarms was evaluated over 13 wet–dry cycles. Check development was variable over the first three to four cycles, and then steadily increased for both plated and nonplated ends of arms; however, both the number of checks and the maximum width of the checks were significantly lower on plated ends. The results suggest that end plating reduces the potential for deep check development in crossarms that could lead to early failure.

Abstract

Peripheral planing of black spruce (Picea mariana) wood was optimized for rake angle and feed speed. Both cutting parameters affected surface characteristics at the microscopic and macroscopic level. In turn, the interaction between rake angle and feed speed had a significant impact on surface roughness, disperse component of surface energy, and total surface energy, as well as on initial pull-off adhesion strength of a waterborne coating. Loss in adhesion during the accelerated aging treatment was significantly lower for samples machined with a rake angle of 10°. This rake angle combined with a wavelength (feed per knife) of 1.3 mm yielded coated surfaces with high initial pull-off strength. Therefore, this wavelength could be used to increase production rates without significantly affecting surface quality. In addition, no torn grain was observed for surfaces prepared with a rake angle of 10° regardless of feed speed.

Abstract

Quaternary ammonium tetraphenylborates (TPBs) and quaternary ammonium tetrafluoroborates were synthesized for the manufacture of leaching-resistant boron wood preservatives. The leachability of these boron compounds and the termite and decay resistance of wood treated with these compounds were evaluated. The boron leaching rate of wood treated with quaternary ammonium TPB formulations ranged from 2.1 to 6.7 percent, while that of quaternary ammonium tetrafluoroborate formulations ranged from 23.3 to 59.0 percent. Quaternary ammonium tetrafluoroborates performed better than quaternary ammonium TPBs in termite resistance and inhibition zone tests. Quaternary ammonium tetrafluoroborates could inhibit Gloeophyllum trabeum and Phanerochaete chrysosporium at all concentrations used in the laboratory inhibition zone test. Weight loss of masson pine (Pinus massoniana) sapwood treated with quaternary ammonium tetrafluoroborate solutions was 1.4 to 2.6 percent (G. trabeum) and 2.5 to 3.8 percent (by Coriolus versicolor) at preservative retentions around 7.0 kg/m³.

Abstract

Two experiments were performed to determine the physical and mechanical characteristics of panels consisting of a veneer face and a particleboard core composed of mixed wood particles/powdered-recycled polyethylene (PE) bag waste (MWP) using urea-formaldehyde (UF) resin as a binder. The addition of 25 percent powdered-recycled PE bag waste to the MWP panels did not adversely affect nonaged bonding strength but did result in substantial improvement in internal bond (IB) retention after a 24-hour water soak and improved dimensional stability. Average MWP panel IB retention was more than 300 percent higher than the IB retention of wood particle (WP) panels and MWP thickness swell and linear expansion were 70 and 44 percent lower, respectively, than the values for WP panels. For the veneer overlay composite, the mean modulus of rupture (MOR) parallel to the surface grain veneer (MOR_||) was lowest (3,668.2 pounds per square inch [psi]) for panels with two veneers cross-laminated on each face over a WP core. Conversely, MOR_|| was greatest (8,535.6 psi) for panels with single 1/8-inch veneers on each face over an MWP core. However, the large percentage of shear failure when stressed parallel to face veneer grain hindered an accurate determination of true MOR. As expected, all specimens tested in bending parallel to the surface grain of the veneers resulted in higher modulus of elasticity (MOE) than those tested perpendicular to the grain. For a single veneer overlay on each face, it is interesting to note that thinner veneers (i.e., 1/8 in.) resulted in higher MOE than thicker veneers (i.e., 3/16 in.).

Abstract

Amino resin wood adhesives used for medium-density fiberboard (MDF), a melamine-urea-formaldehyde (MUF) resin and a urea-formaldehyde (UF) resin, were each synthesized with an overall formaldehyde/urea molar ratio of 1.10. The storage stability of the resins was monitored by their gel times and viscosity changes, as well as by a multiple light scattering method. The storage stability tended to be affected by the temperature at which the resins were stored. MUF resin had a higher storage stability at a storage temperature above room temperature, whereas UF resin exhibited the best storage stability at 10°C with overall good stability at all tested temperatures from 10°C to 40°C.

Abstract

The main goal of this work was to use rice straw fiber as a filler in the production of environmentally sound decorative materials using cornstarch adhesives as matrix. Treatments of rice straw with NaOH, oxalic acid, and hot water were undertaken to evaluate the effect of such treatments on the characteristics of rice straw and the performance of produced materials. The influence of temperature and shear rate on apparent viscosity of cornstarch adhesives was also investigated. Results showed that all treatments were efficient in partially modifying rice straw surface properties, as evidenced by Fourier transform infrared spectroscopy, and improving wettability of rice straw. Scanning electron microscopy suggested that NaOH and hot-water treatments resulted in a more significantly changed rice straw substrate than oxalic acid treatments. Apparent viscosity of the cornstarch adhesive decreased with increasing shear rate and increased and then decreased with increasing temperature, reaching a peak value at 10°C. The dependence of physical–mechanical properties of obtained materials on treatments performed on rice straw was also studied. Hot-water–treated straw materials displayed the best set of final mechanical properties. The materials exhibited poor waterproof performance but considerable moisture resistance and environmental friendliness, and such materials could be used for indoor decorative materials.