The Balsa Conundrum

This photograph originally appeared in the 2013 Research student photography and image competition held to celebrate National Science Week (Aug 10-18). Blurb: Sustainability does not only refer to the impact that 'consumers' have on the environment, it refers to social and economic sustainability, which are equally significant. In order to claim we are sustainably developing on a global level we must ensure that environmental, social and economic sustainability are balanced. Current trends indicate mass growth in developing countries such as China and India, where an influx of necessary liveable accommodations are required at affordable costs. In recent times the balsa wood industry in Papua New Guinea has shown substantial growth indicating true sustainable practice. Because balsa is a renewable resource it offers competitive environmental elements to existing non-renewable resources such as synthetic foams. Economic returns to smallholders growing balsa help sustain social developments for communities in Papua New Guinea. Balsa is currently overstocked in Papua New Guinea as consumers turn to synthetic foams, yet balsa could become a cheap commercial building material for developing countries offering sustainable and affordable housing. The balsa conundrum

The view up here - research to commercialisation

This photo received first place in the 2015 Research student photography and image competition held to celebrate National Science Week (Aug 15-23). Blurb: "The view up here: research to commercialisation" presents the product outcome of my design research - a lightweight, truly sustainable interior acoustic lining panel which utilises Papua New Guinea (PNG) balsa wood as a core substrate material in sandwich panels. The photograph represents the significant scale of this research outcome. Balsa farmers in PNG rely heavily on this resource for financial returns to support their family and community livelihoods. A lack of design innovation has resulted in a mass over-supply and under-demand for PNG balsa in global markets. The development of a new balsa product outcome has a significant impact on PNG farmers and the PNG balsa industry by offering alternative consumer markets. Additionally, this product innovation demonstrates an opportunity to generate global demand for PNG balsa as a sustainable alternative to current building materials used in the construction industry. Balsa is one of the lightest commercial timbers available and the only material used in sandwich composite panels to derive from a natural and renewable resource grown on sustainable plantations. My research has proven that balsa has superior thermal performance and acoustic absorption properties that make it a desirable material for lightweight, interior fit-outs where thermal comfort and noise control are essential in contemporary high-rise concrete construction. This design research outcome has been installed into commercial environments and has successfully delivered premium results for clients proving it is a commercially viable and innovative design outcome

Designing a balsa revolution

This photograph originally appeared in the 2014 Research student photography and image competition held to celebrate National Science Week (Aug 16-24). Blurb: People often reminisce on childhood memories of model making when they think about balsa wood, however history has seen balsa used predominately in marine and aviation industries. In the 21st century balsa is found in applications that optimise the sustainable properties and lightweight nature of the material. Such applications include wind turbine blade manufacturing for wind energy generation and as a core catalyst in sandwich composites for the automotive industry. Balsa is a natural timber that grows very fast in Papua New Guinea (PNG). Since the Global Financial Crisis (GFC) balsa exports have declined resulting in a mass over-supply and under-demand for balsa causing hardship for balsa growers. Making matters worse is the fact that balsa consumers prior to the GFC are now consuming synthetic foams as a substitute material regardless of the environmental concerns synthetic materials poses. There is a need for designers to generate new concepts that promote the use of balsa in new applications to generate international demand for the material. The mechanical strength, thermal conductivity and acoustic properties of balsa have been tested to identify new markets and concepts worthy of design exploration. There is an opportunity to design new applications for balsa which can be implemented into the construction industry as an affordable, sustainable, thermal and acoustic insulator. Design innovation is the key to revolutionise the balsa industry

Study on the Effect of Finger-Joints on the Strengths of Laminations from Fiber-Managed <i>Eucalyptus nitens</i>

The performance characteristics of finger-joints as a jointing technique for Eucalyptus nitens is crucial for their use in engineered wood products. This research evaluated the strength of the finger-jointed laminations made from fiber-managed E. nitens. A total of 237 specimens with (117 pieces) and without (120 pieces) finger-joints were sectioned from finger-jointed laminations and tested by bending, tensile, shear, and bearing tests. Bending and tensile tests were paired to identify any correlations. The mean value with finger-joints for bending and tensile were 92.1 MPa and 79.6 MPa, respectively. The presence of finger-joints reduced the strength values. Joint efficiencies in bending and tensile are 0.73 and 0.62, respectively. The distributions of bending and tensile strength were similar for the samples without finger-joints. For the samples with finger-joints, tensile strength was significantly lower than paired bending strength. Shear test results show that the short-span test is inefficient in obtaining the shear strength of fiber-managed E. nitens boards. Meanwhile, the finger-joint efficiency in the bearing is 0.86. The prediction models of lamination’s bending, tensile, and bearing strength were established by non-destructive properties as predictors. Bending strength was highly correlated to the modulus of elasticity value, while tensile and bearing strength were correlated to density. This study obtained promising results on finger-jointed boards from fiber-managed E. nitens suggesting they could be suitable for structural purposes

What to Do with Structurally Low-Grade Wood from Australia’s Plantation Eucalyptus; Building Application?

About one million hectares of plantation hardwoods, mostly eucalyptus trees of different sub-species (E. nitens and E. globulus), are annually being managed in Australia, which provides a promising resource of raw materials for fibre industries. However, the timber boards required by the Australian hardwood sector are still being either imported from other countries or harvested from the native forests. There is a need to find a practical way to use the plantation eucalyptus in the Australian timber industry. However, the fibre-managed plantation eucalyptus produces structurally low-grade timber which could not be used as individual boards for structural applications—such as building construction. Unsuitable for appearance applications, the structurally low-grade boards may be suitable for producing innovative high-mass engineered timber products. This editorial will briefly discuss drivers, opportunities, and challenges associated with conducting such a research project

Study on the Effect of Finger Joints on the Stiffness of Fibre-Managed <i>E. nitens</i> Sawn Boards

Fibre-managed E. nitens has the potential to be used as a feedstock for engineered wood products. This resource, however, has a number of strength-reducing features that need to be removed, and the board needs to be re-joint to be useful in greater lengths for timber construction. A common jointing practice is finger jointing. The suitability of the finger jointing technique for this species is crucial to the mechanical properties of the final product. This study was conducted to explore the influence of finger jointing on the stiffness of sawn boards. A strict manufacturing process of docking and re-joining timber boards in the same location without removing strength-reducing features was conducted to compare the stiffness parameters before and after finger jointing with bending tests. A statistical analysis was conducted. The results showed that the frequency of finger joints along the board did not significantly impact the edgewise stiffness; however, the average flatwise stiffness of the samples with more finger joints was improved slightly. A 10% increase in the end pressure reduced the tip gap significantly but did not influence the stiffness. The finger joint efficiency was 0.824 for the edgewise stiffness of the samples and 1.034 for flatwise stiffness of the jointed sections

Structural Properties of Commercial Australian Plantation Hardwood CLT

Significant volumes of plantation hardwood are available in Australia to produce value-added engineered wood products such as cross-laminated timber (CLT). To validate the possibility of utilising this available resource, the bending structural properties of plantation Eucalyptus nitens solid board and finger-jointed feedstock were measured. The studied CLT panels produced from finger-jointed lamellas were subjected to bending strength, bending stiffness, rolling shear strength in bending, and pure rolling shear tests to obtain characteristic design values. Solid and finger-jointed timber test results suggested that boards used in longitudinal lamellas have a bending strength of 36.0 MPa and a modulus of elasticity (MOE) of 13,000 MPa. Finger-jointed timber in crossed lamellas presented a declared bending strength of 25.0 MPa. CLT panels showed a bending strength of 24.0 MPa and a rolling shear strength of 2.0 MPa. The experimental results for the CLT panels evidenced that the CLT bending stiffness matches up very well with the modelled results when an MOE of 13,000 MPa is used to describe the stiffness of longitudinal boards. The results presented in this study establish a basis for the commercial use of Australian plantation hardwood CLT in structural applications such as floors and roofs in commercial and residential buildings

Thermal conductivity of Papua New Guinea balsa wood measured using the needle probe procedure

A study was undertaken with the aim to determine thermal properties of balsa wood grown in plantations in Papua New Guinea. Thermal conductivity values were measured using the needle probe procedure according to ASTM D5334 (2008). The mean thermal conductivity results of balsa were in the range of 0.0381 W/mK to 0.0665 W/mK, similar to other materials currently used as insulators in the construction industry. A balsa sample with a density of 113 kg m3 had the lowest thermal conductivity value, 0.0339 W/mK, across the tangential and radial wood grain directions. Balsa is exported from Papua New Guinea mostly as end-grain panels to international markets to optimise its strength properties in the axial direction for applications that are exposed to compressive forces. This study revealed that there is the opportunity for Papua New Guinea balsa processors to consider producing perpendicular-grain panels for insulation markets, as the mean thermal conductivity values in this direction can be as low as 0.0381 W/mK, which is much lower than the thermal conductivity of the current end-grain panels at 0.0665 W/mK. The finding creates a potential design opportunity for balsa processors to consider entering new commercial markets to promote Papua New Guinea-grown balsa

Machinability Study of Australia’s Dominate Plantation Timber Resources

This study tested the machinability of three major timber species grown in Tasmania, Australia, under different resource management schemes: plantation fiber-managed hardwood (Eucalyptus globulus Labill. and Eucalyptus nitens Maiden) and plantation sawlog-managed softwood (Pinus radiata D. Don). P. radiata was used as a control to identify significant differences in machining fibre-managed plantation timber against sawlog-managed plantation timber with numerically controlled computer technology and manually fed timber production techniques. The potential to fabricate architectural interior products such as moldings with plantation fiber-managed hardwood timber that is high in natural features was the focus of this study. Correlations between wood species, variation in moisture content, and density of individual machinability characteristics were analyzed to determine factors impacting the overall quality of plantation wood machinability. Correlations between species and within species groups from the resulting machinability tests are highlighted and discussed. The results indicate that the machinability of sawlog-managed softwood P. radiata is superior in some circumstances to fiber-managed hardwood E. globulus and E. nitens specimens, according to the American Society for Testing and Materials D1666-11.Peer reviewe