Summarizes information on wood as an engineering material. Presents properties of wood and wood-based products of particular concern to the architect and engineer. Includes discussion of designing with wood and wood-based products along with some pertinent uses.

Wood handbook : wood as an engineering material

Modeling chemical and physical processes of wood and biomass pyrolysis

A diverse array of fire-adapted plant communities once covered the eastern United States. European settlement greatly altered fire regimes, often increasing fire occurrence (e.g., in northern hardwoods) or substantially decreasing it (e.g., in tallgrass prairies). Notwithstanding these changes, fire suppression policies, beginning around the 1920s, greatly reduced fire throughout the East, with profound ecological consequences. Fire-maintained open lands converted to closed-canopy forests. As a result of shading, shade-tolerant, fire-sensitive plants began to replace heliophytic (sun-loving), fire-tolerant plants. A positive feedback cycle—which we term “mesophication”—ensued, whereby microenvironmental conditions (cool, damp, and shaded conditions; less flammable fuel beds) continually improve for shade-tolerant mesophytic species and deteriorate for shade-intolerant, fire-adapted species. Plant communities are undergoing rapid compositional and structural changes, some with no ecological antece...

The Demise of Fire and “Mesophication” of Forests in the Eastern United States

A review on the degradability of polymeric composites based on natural fibres

A simple and facile method for obtaining patterned graphene under ambient conditions on the surface of diverse materials ranging from renewable precursors such as food, cloth, paper, and cardboard to high-performance polymers like Kevlar or even on natural coal would be highly desirable. Here, we report a method of using multiple pulsed-laser scribing to convert a wide range of substrates into laser-induced graphene (LIG). With the increased versatility of the multiple lase process, highly conductive patterns can be achieved on the surface of a diverse number of substrates in ambient atmosphere. The use of a defocus method results in multiple lases in a single pass of the laser, further simplifying the procedure. This method can be implemented without increasing processing times when compared with laser induction of graphene on polyimide (Kapton) substrates as previously reported. In fact, any carbon precursor that can be converted into amorphous carbon can be converted into graphene using this multiple l...

Laser-Induced Graphene by Multiple Lasing: Toward Electronics on Cloth, Paper, and Food

As part of a study of the charring rate of wood, I determined the higher heating values (gross heat of combustion) and the chemical composition of samples from four hardwoods and four softwoods. The higher heating value of wood was correlated with lignin and extractive contents. There was a highly significant linear correlation between the higher heating value of the extractive-free wood and lignin content. Equations are presented that can be used to determine the higher heating value of extractive-free wood when the Klason lignin content is known. The equations should be useful to those interested in using a variety of species of wood as fuel.

/pdf/effect-of-lignin-content-and-extractives-on-the-higher-sbkmtz5hus.pdf

Effect of lignin content and extractives on the higher heating value of wood

https://www.fpl.fs.fed.us/documnts/pdf2010/fpl_2010_stark002.pdf

Evaluation of various fire retardants for use in wood flour-polyethylene composites

In this study, physical, mechanical, and flammability properties of coconut fiber reinforced polypropylene (PP) composite panels were evaluated. Four levels of the coir fiber content (40, 50, 60, and 70 % based on the composition by weight) were mixed with the PP powder and a coupling agent, 3 wt % maleic anhydride grafted PP (MAPP) powder. The water resistance and the internal bond strength of the composites were negatively influenced by increasing coir fiber content. However, the flexural strength, the tensile strength, and the hardness of the composites improved with increasing the coir fiber content up to 60 wt %. The flame retardancy of the composites improved with increasing coir fiber content. The results suggest that an optimal composite panel formulation for automotive interior applications is a mixture of 60 wt % coir fiber, 37 wt % PP powder, and 3 wt % MAPP.

https://www.fpl.fs.fed.us/documnts/pdf2011/fpl_2011_ayrilmis002.pdf

Coir fiber reinforced polypropylene composite panel for automotive interior applications

Burning rate is a key factor in modeling fire growth and fire endurance of wood structures. This study investigated the burning rate of selected wood materials as determined by heat release, mass, loss and charring rates. Thick samples of redwood, southern pine, red oak and basswood were tested in a heat release rate calorimeter. Results on ignitability and average heat release, mass loss and charring rates are reported for a heat flux range between 15 and 55 kw m−2. In this range, burning rate increased linearly with heat flux. Burning rate was very species dependent. Heat release rate was related to mass loss by effective heat of combustion, which also increased with heat flux. Charring rate was related to mass loss rate and original wood density. Important char property data such as yield, density and contraction are reported. A simplified calculation method is proposed for calculating mass loss rate and charring rate based on heat release rate.

https://www.fpl.fs.fed.us/documnts/pdf1992/tran92b.pdf

Burning rate of solid wood measured in a heat release rate calorimeter

Knowledge of how species differ in their flammability characteristics is needed to develop more reliable lists of plants recommended for landscaping homes in the wildland-urban interface (WUI). As indicated by conflicting advice in such lists, such characterisation is not without difficulties and disagreements. The flammability of vegetation is often described as having four components (ignitability, combustibility, sustainability and consumability). No standards or generally recognised test procedures exist for evaluating these components in plants. Some measurements of flammability include times for ignition, rate of flame spread, flame height and heat release rate. Often, the fire behaviour characteristics of a plant are derived from its physical and chemical characteristics. Thermogravimetric analysis and other thermal analyses of ground samples have long been used to characterise the thermal degradation of vegetation. More recently, researchers have used the oxygen consumption methodology to measure the heat released due to combustion of the vegetation. Although oxygen consumption calorimetry is an improvement in characterising plant flammability, translation of laboratory results to field conditions can be problematic and tests can be expensive.

/pdf/testing-and-classification-of-individual-plants-for-fire-4a1rvdh2aj.pdf

Robert H. White

Papers

Effect of lignin content and extractives on the higher heating value of wood

Evaluation of various fire retardants for use in wood flour-polyethylene composites

Coir fiber reinforced polypropylene composite panel for automotive interior applications

Burning rate of solid wood measured in a heat release rate calorimeter

Testing and classification of individual plants for fire behaviour: plant selection for the wildland-urban interface