VOLUME 56, ISSUE 2/2015

At the Institutes of Plant and Wood Chemistry as well as Wood and Paper Technology, both of Technische Universität Dresden, an environmentally compatible flame retardant based on derivatized renewable raw materials was developed. Starch-phosphate-carbamate is formed during simultaneously derivatisation of starch with phosphoric acid and urea. The properties of phosphates and carbamates are combined in this product. The positive effect of this flame retardant was already shown during tests under norm conditions. The water solubility of the polysaccharides makes an intrinsic as well as an extern treatment of the wood-based materials with flame retardant possible. So all raw materials for the intumescence are combined in a water soluble starch product. This allows an easy and cost-efficient equipment of wood-based materials for improving the fire protection. Currently a technology for producing starch-based flame retardants in a commercial scale is developed and the usage of this material in wood fibre insulating materials is planned.

The ability to assess processed wood surfaces with 3-D surface measurement techniques permits differentiated meanings about the influence of wood species, the processing procedure and the moistening on the topology of these surfaces. Seven wood species are examined with respect off the influence of the thermal smoothing and sanding processing method on the surface topology. The results are compared. Furthermore the effect is measured, which is produced by moistening of the processed surfaces. The resistance of the generated surfaces of the different wood species with the two machining processes is shown. It is judged which roughness parameters are suitable to evaluate the surface topology of wood.

The Landesgartenschau Exhibition Hall is an architectural prototype building and a showcase for the current developments in computational design and robotic fabrication for lightweight timber construction. Funded by the European Union and the state of Baden- Württemberg, the building is the first to have its primary structure entirely made of robotically prefabricated beech plywood plates. The newly developed timber construction offers not only innovative architectural possibilities; it is also highly resource efficient, with the load bearing plate structure being just 50 mm thin. This is made possible through integrative computational design, simulation, fabrication and surveying methods.

As the result of the work, a measuring device for determination of formaldehyde release of particles from wood-based panels was developed which is intended to use as part of an overall inline-monitoring concept in wood-based materials production. The measuring results provide information about the course of the process, which could serve as a basis for optimization. For this purpose, particles obtained from the exhaust of the diagonal saw and the edge trimmer of particle boards respectively are transported to the measuring equipment. The results of industrial tests indicate the suitability for its use under industrial conditions. Measurable and distinguishable formaldehyde release values from particle boards with low emission levels can be also detected. It was possible to establish a product and plant specific correlation between the formaldehyde release of particles and the formaldehyde amount as well as the formaldehyde emission from the corresponding wood-based plates. Further work will focus on the implementation of the equipment in production processes.

In many cases only few wood species are used or even considered for any given wooden product, even though there are hundreds of wood species available. The objective of this project was the development of a time efficient and structured method to identify the most suitable wood species for wooden products, based on a set of required material properties. This goal was achieved by applying multivariate data analysis. The method was based on a dataset consisting of commercially available wood species represented by many different properties. The scores and loadings of the multivariate data analysis method Principal Component Analysis (PCA) were used to identify the wood species with the most fitting property combinations for the product in question. Applying the method to an example case resulted in several plausible alternatives to the commonly used wood species. It is possible to apply the method to any wooden product by determining the set of required properties.

In mechanical engineering, the socio-political discussion on sustainability and energy efficiency generates the demand for equivalent constructions. Requested are technical solutions that offer the companies opportunities to increase their business contribution to sustainable development and to achieve economic benefits. These designs require sustainable, eco-friendly and thus “ecologically beneficial" construction materials. Selected wood materials represent one possibility for such materials. To investigate the ecological impact of these substitution materials in a transparent manner, the categories of global warming potential and primary energy demand will be used. Both factors are describing sustainability and environmental friendliness the most accurately. The analysis should clarify the ecological benefits of wood veneer composites, structural steel, galvanized steel and aluminium alloys in the life phase of production as well as with the impact categories global warming potential and primary energy consumption. Thus, the comparison of materials takes place only partially.

Since the middle of the 20th century several studies concentrate on the mathematical description of the cutting process of wood. Application of existent approaches (empirical, analytic, statistical, numerical, and semi-empirical) is not or limited due to the high amount of influencing factors and not existing parameters, respectively. For that reason different approaches are presented and discussed critically within these three parts of the review. Based thereon a basic concept as well as different solutions for the generation of a user-friendly cutting force model is presented.