Completed research projects
Project manager TU Dresden: Prof. Markus Rüggeberg
Project duration: 01.10.2022 to 31.03.2025
Project partner: Institute for Computer-Based Design and Drafting, University of Stuttgart
Funded by: Federal Institute for Research on Building, Urban Affairs and Spatial Development (BBSR) on behalf of the Federal Ministry of Housing, Urban Development and Building (BMWSB) Innovation Program Future Building.
The research project is investigating the use of self-forming wood for the production of cylindrical, load-bearing components in the construction industry. This innovative technology utilises the hygroscopic properties of wood in a targeted manner to create a predefined curvature in the components through controlled changes in moisture. The technology promises to offer a resource-saving alternative to mechanically bent or milled timber structures, as the forming is carried out without high energy input or complex mechanical processes. Curvatures have great potential in the construction industry, as they can improve both the material efficiency and the static performance of load-bearing structures when used in a targeted manner. A curved geometry can increase the rigidity of a component without additional material. This enables lightweight and high-performance designs with reduced material usage. Traditionally, efficient, curved shapes are often realised with mineral building materials such as concrete or masonry. The use of self-forming timber components opens up a sustainable alternative here, as it makes it possible to realise such geometries with a renewable raw material.
As part of the project, existing fields of application for curved components were investigated and evaluated on the basis of their suitability for self-forming cylindrical components in order to narrow down a design space. The results show that self-forming timber components are generally suitable for structural applications. They offer a promising alternative to conventional production methods, particularly in the context of sustainable construction methods. The further development of bonding and manufacturing technologies could further facilitate industrial application and contribute to the establishment of this construction method in future projects.
Acronym: addwood
Project manager: Dr.-Ing. Michael Rosenthal
Duration: 01.04.2020 - 30.09.2023
Project sponsor: BMEL (FNR)
So far, mainly subtractive manufacturing processes have been used in wood processing. The material efficiency of these production technologies is naturally limited. By using alternative technologies, the amount of wood waste can be reduced or used for the production of goods. Liquid deposition modeling (LDM) is a 3D printing process that works with pasty materials. In preliminary work, material mixtures for liquid deposition modeling were developed at TU Dresden with a particular focus on ecological aspects, using water-based binders made from renewable raw materials (e.g. methyl cellulose, starch). The research project continued the material development.
Compressible mixtures with softwood chips were developed and shrinkage, flexural strength and material density were investigated. The use of alternative binders (gypsum), additional reinforcing fibers (cellulose) and fillers (sand) influenced the physical properties. A practical material mixture served as the basis for further work.
In collaboration with the West Saxon University of Applied Sciences in Zwickau, the process was transferred from laboratory to pilot scale. Together, a continuously operating twin-screw extruder was developed. This was used to produce larger objects, which were tested by the WHZ for their suitability in furniture production.
Project manager: Dr.-Ing. Michael Rosenthal
Duration: 01.10.2020 - 30.09.2022
Project sponsor: DLR (BMBF)
Liquid Deposition Modeling (LDM) is an additive, extrusion-based manufacturing process. Up to now, mineral materials such as clay or concrete have primarily been used. The task of the project was to further develop the printing process and develop suitable, bio-based materials. The focus was on renewable raw materials - forestry residues on the German side, agricultural residues on the side of the Egyptian project partner (German University in Cairo).
Extensive laboratory work was carried out to determine the physical properties of test specimens produced using liquid deposition modeling and to develop a laboratory extruder. The investigations made it possible to understand the influence of selected mixture components (e.g. starch, salt, cement, wood flour) on the physical properties. This is an essential prerequisite for the future optimization of material properties. With the help of an external partner's 3D printer, an initial furniture demonstrator was produced based on the previous tests. Due to the limited stability of the freshly processed bio-based printing material, the possible print or object height was limited.
Project manager: Prof. Dr. Dr. Bues
Duration: 2018 - 2021
Sustainable Dendromass Production and Innovative Bio-based Materials from Poplar Plantations in European Rural Areas
Dendromass4Europe (D4E) aims at establishing sustainable, Short-Rotation Coppice (SRC)-based regional cropping systems for agricultural dendromass on marginal land that feed into bio-based value chains and create additional job opportunities in rural areas. For that purpose, 2,500 ha of short rotation poplar plantations are established, including marginal or currently unused land in rural areas of the Slovak Republic and Hungary. These plantations will provide the feedstock for the establishment of four new bio-based value chains based upon products from wood and bark from poplar trees: (1) a functionally adapted lightweight fibreboard, (2) eco-fungicidal moulded fibre parts, (3) a bark-enriched woodplastic composite and (4) a multi-purpose wood-plastic granulate.
Besides developing attractive business opportunities, the activities of the industrial partners in D4E will generate profit for the rural economy (income for farmers, employment opportunities). A large number of farmers and rural land owners will directly benefit from the diversification and increase of revenues through their involvement into D4E. The main responsible plantation owner IKEA Industries Malacky provides a framework for land acquisition. Based on the impact of D4E plantations for the farmers' income, new primary agricultural jobs will be created. New green jobs in rural areas will also originate from the D4E at the production plants of the industrial partners. The consortium D4E unites expertise from industrial and academic partners in the relevant fields along the production, processing and utilization of products from short-rotation coppice.
Harvesting, debarking, field logistics, log storage
At the operation management level, a dedicated project team will focus on designing, testing and demonstrating alternative harvesting and supply chains for the efficient felling, processing, extraction and transportation of wood products from SRC. Supply chains will be designed for meeting the required quality specifications within the set cost threshold, while complying with all environmental, social and market constraints. A continuous supply with raw material is essential for the implementation of a new industrial processing line. The harvest of SRC dendromass can only take place when the trees are dormant during the winter months. The storage of the raw material is an important aspect for the successful implementation of the value chain, especially in the summer months, when no freshly harvested wood is available. Strategies and technologies for dendromass are manifold. The duration and type of storage greatly influence wood quality and with that the quality of the respective end product. The main risks associated with long-term wood storage are e.g.: formation of wood cracks after drying or seasoning the external log parts too close to fiber saturation point; discoloration; infestation with insects; and destruction of the wood by infestation with fungi. Depending on the duration of storage, a number of factors can contribute to a reduction in wood quality, demanding for various kinds of storage strategies.
The objective of log storage is to optimize the method for the storage of poplar trunks over a period of up to 8 months. Three different storage methods: a) Storage in compact pile; b) Log conservation under oxygen exclusion; c) Storage in compact pile with water sprinkling - will be evaluated regarding its impact to wood quality as well as ecological and economical aspects. Furthermore, the differences in wood quality and drying of logs stored with and without bark will be evaluated. All parameters of the storage principles will be evaluated and if necessary adapted to the specific industrial process requirement. Wood quality during the storage/conservation period will be monitored and controlled continuously. Finally, it is necessary to test whether the stored raw material undergoes changes in its anatomical, chemical, and physical composition, which may influence the wood processing technique and the characteristics of the end product. Based on the analysis results an operating procedure for the optimum storage method will be created.
Project manager: Prof. Dr. Dr. Bues
Duration: 03.01.2017 to 05.31.2020
The search for CO2-neutral energy sources and the finite nature of certain resources mean that the demand for wood is constantly increasing. Wood is not only in greater demand from the energy sector (heating, power generation, biofuels), high growth rates are also forecast in the material-mechanical and chemical sectors. Wood is increasingly becoming a scarce commodity, as various wood supply forecasts for Europe and the Federal Republic of Germany show.
The increasing demand can only be covered to a limited extent by increased use of the growth potential. However, this "gap" could be covered to a considerable extent by high-performance breeding products, since the specific requirements for yield (volume and mass) as well as the qualities for the sawmill, wood-based materials and paper industries are met here. The results of forest plant breeding are an important starting point for improving the productivity of forests in the medium to long term.
Hybridlärche_WoodforIndustry
The use of reproductive material that has already been improved by breeding - such as aspen, Douglas fir and hybrid larch - enables shorter rotation times due to the up to 80% better growth (hybrid larch). As a result, site productivity can be increased and silvicultural strategies can be handled more flexibly.
When it comes to the material use , the question arises as to whether the changed growth rates also result in changed wood properties. In order to be able to use the existing breeding material economically, its properties must be extensively examined.
The research contribution of the professorship for forest use to the joint project "Wood for Industry" consists of creating a wood technology profile for the various tree species and hybrids, from which potential areas of application as solid wood, wood-based materials and as a raw material for the pulp and paper industry can be derived.
Project Partner
State enterprise Sachsenforst (project coordinator)
Department of Forest Genetics/Forest Plant Breeding
Institute for Wood Technology Dresden non-profit GmbH
Department of biology/wood protection
Technical University Dresden
Institute for plant and wood chemistry
Professorship for forest botany Professorship for Forest Utilization
The project is funded by the Agency for Renewable Resources FNR.
Project manager: Prof. Dr. Dr. Bues
Duration: 01.06.2017 to 31.05.2019
3D printing is a process in which three-dimensional objects are created from a digital file by building up material layer by layer under computer control. The "WOO-3D" project consists of two parts:
(1) A course at Bethlehem University aims to familiarize scientists and students with basic engineering processes involved in creating 3D printable models and using 3D printing as a means of computer-aided manufacturing in fields such as engineering, architecture and consumer products.
(2) The material development of 3D printer filaments with special properties is still in its infancy. This project aims to contribute to the development of 3D printer filaments with wood-like properties. Material-related and technological factors will be investigated as a basis for proposing improvements to the material composition and the manufacturing process.
After storm damage in forests or other forest calamities, it is necessary to store logs for longer periods of time. This log storage is intended to prevent an oversupply of calamity timber on the log market and the associated price collapse. The most common and so far safest storage method for round timber is the sprinkling of densely piled logs. However, experience after the last storm disasters in 1990 has shown that even irrigated logs can be devalued by fungal infestation under certain circumstances.
In cooperation with the FVA Baden-Württemberg, the aim of the research work was therefore to develop and test a cost-effective new storage method for logs, which preserves the properties and quality of the stored wood - if necessary over several years - and thus represents an attractive alternative or supplement to the usual wet storage.
The starting point for the research project was the knowledge that in agriculture, the food industry and fruit growing, goods are permanently preserved by inert gas storage.
| Brief description | |
| Project leader: | Prof.Dr.Dr. C.T. Bues |
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| Collaborators: | M.Sc. Erwinsyah |
| Funding/Partner: | Indonesian Oil Palm Research Institute (IOPRI) |
| Duration: | 06/05-12/07 |
| Brief description | |
| Project leader: | Prof.Dr.Dr. C.T. Bues |
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| Collaborators: | Simone Stübner (Dipl.-Forstwirtin) |
| Funding/Partner: |
Germany:
Brazil:
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| Duration: | 03/99 - 08/05 |
| Brief description | |
| Project leader: | Prof.Dr.Dr. C.T. Bues |
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| Collaborators: | M.Sc. Abukari Nantogmah Attah |
| Funding/Partner: |
Forestry Commission: Timber Industry Development Department Takoradi / Ghana |
| Duration: | 01/02 - 08/05 |
| Brief description | |
| Project leader: | Prof.Dr.Dr. C.T. Bues |
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| Collaborators: | M.Sc. Erwinsyah |
| Funding/Partner: |
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| Duration: | 10/02 - 03/04 |
| Brief description | |
| Project manager: | Dipl. Forsting. Bäucker |
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| Collaborators: | |
| Funding/Partners: |
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| Term: | since 2011 |
Subproject 3.1
"Utilization-relevant properties of sessile oak weakwood from mixed stands"
| Brief description | |
| Project leader: | Prof.Dr.Dr. C.T. Bues |
|---|---|
| Collaborators: | Dipl.-Forsting. E. Bäucker |
| Funding/Partner: | BMBF funding code: 0330576 |
| Duration: | 05/05 - 04/09 |
Sub-topic: "Examination of cell formation using microsamples": The collection of microsamples is a particularly tree-friendly method for examining cell formation in the phloem and in the outer xylem growth rings. Microsamples are taken with the aid of medical syringe needles and prepared for the light microscopic examination of cell formation within the growth ring. The very small wounds are safely sealed and sealed by the reaction of the tree. Samples can be taken frequently and very close together on the tree, allowing the vitality of coniferous and deciduous trees to be determined at any given time thanks to the exact timing of cell formation.
Sub-topic: "Nutrient element content of selected tissues of spruce needles from the desiccation experiment and of a comparison spruce": Using X-ray microanalysis, element contents in the vacuoles of the needle tissues endodermis, mesophyll and, for orientation, in the cambium of the vascular bundle were investigated. The measurements included needles from two spruces from the dry stress test and the comparison spruce. As a result of the investigations, significantly lower concentrations of potassium and magnesium were found in the dry stress variant, particularly in the endodermis, but also in the mesophyll and in the cambial area of the vascular bundle. Coupled with the drought stress, the experimental spruces appear to have been exposed to an extreme nutrient deficiency.
The objective of the State Innovation College "Thermal Insulation Systems" at the TUD was to investigate new insulation materials made from renewable raw materials with regard to their suitability for thermal and sound insulation in dry construction and their behavior in the building.
Important results of the sub-project worked on by the Chair of Forest Utilization (funding amount over the total term DM 420,203 (214,846 euros)) consisted of the reproducible production of water glass-bonded insulating materials from renewable raw materials and recycled products, their installation and the testing of important properties in long-term tests.
The process development was driven through to the production planning of the gassing and drying plant for the continuous production of insulation materials.
The development results were implemented in 1999 by a company in the insulation materials industry up to the small-scale plant. The aim is the large-scale production of water glass-bonded insulating materials.
Aufgabenstellung
Die Fortführung des Waldumbaues in der Region erweitert den Anteil von Traubeneichen-Kiefern-Mischbeständen. Die nachhaltige Bewirtschaftung dieser Bestände erfordert eine Nutzung zwangsläufig anfallenden Eichenschwachholzes mit möglichst hoher Wertschöpfung. Daher erfolgte eine Erarbeitung von gesicherten Aussagen zu der Verteilung der Rohholzqualitäten in Traubeneichen-Kiefern-Mischbeständen auf den ausgewählten Standorten.
Forschungsziele
Auswahl repräsentativer Untersuchungsbestände entlang eines Kontinentalitätsgradienten, eines Altersgradienten und nach Varianten von waldbaulichen Verfahren.
Gewinnung von Aussagen zur Holzqualität für eine repräsentative Anzahl von Beständen.
Entwicklung von spezifischen Untersuchungsmethoden für die Qualitätsansprache von Eichenschwachholz für Mischbestände.
Erarbeitung eines Sortiermerkblattes für Eichenschwachholz als Arbeitsgrundlage für Holzabnehmer und Waldbauer.
Fortführung des Waldumbaus mit einem hohen Anteil an Traubeneichen-Kiefern-Mischbeständen befriedigender Qualität für spezielle Verwendungszwecke.
Methoden
Auswahl repräsentativer Untersuchungsbestände entlang eines Kontinentalitätsgradienten, eines Altersgradienten und nach Varianten von waldbaulichen Verfahren. Die Untersuchungen erfolgten für Bestände repräsentativer Standorte der Region und unterschiedlicher waldbaulicher Begründungs- und Behandlungsvarianten.
Durch Beurteilung der Rohholzqualität anhand von äußeren Sortiermerkmalen (Verwendungssortenanteile, Güteklassen) und ergänzende Untersuchung innerer Holzeigenschaften konnten Aussagen über die Verwendbarkeit des bei der Bestandespflege anfallenden Holzes gewonnen werden.
Begrenzende Qualitätskriterien (Sortiermerkmale) für die Verwendung von Eichenschwachholz als Sägeholz wurden ermittelt.
Die Ableitung der Verwendbarkeit erfolgte durch Ansprache von sortierentscheidenden Dimensions- und Qualitätsmerkmalen am stehenden und liegenden Stamm. Ergänzend wurden an Stichproben Stammanalysen durchgeführt und innere Holzmerkmale untersucht.
Begrenzende Qualitätskriterien wurden in Zusammenarbeit mit Holzverarbeitern und anhand technologischer Parameter in Abhängigkeit von der Verwendungsart erarbeitet.
Veröffentlichungen: .
Bäucker, E.; Bues, C.T. (2009): Holzqualität von Traubeneichen-Kiefer-Mischbeständen. Forst und Holz 64 (3): 25 - 30 . Elmer, M.; Kätzel, R.; Bens, O.; Bues, C.T.; Sonntag, H.; Hüttl, R. (Hrsg.) (2009): Nachhaltige Bewirtschaftung von Eichen-Kiefern-Mischbeständen im Spannungsfeld von Klimawandel, Waldumbau und internationalem Holzmarkt. oekom Verlag München, 160 Seiten.
Bäucker, E.; Bues, C.T. (2009): Holzeigenschaften von Traubeneichen-Schwachholz. In: Elmer, M.; Kätzel, R.; Bens, O.; Bues, C.T.; Sonntag, H.; Hüttl, R. (Hrsg.) (2009):
Nachhaltige Bewirtschaftung von Eichen-Kiefern-Mischbeständen im Spannungsfeld von Klimawandel, Waldumbau und internationalem Holzmarkt. oekom Verlag München: 67 - 85 .
Suckow, F; Schröder, J.; Bäucker, E.; Elmer, M.; Frommhold, H.; Lange, M. (2009): Grundlagen und Forschungsfragen. In: Elmer, M.; Kätzel, R.; Bens, O.; Bues, C.T.; Sonntag, H.; Hüttl, R. (Hrsg.) (2009). Nachhaltige Bewirtschaftung von Eichen-Kiefern-Mischbeständen im Spannungsfeld von Klimawandel, Waldumbau und internationalem Holzmarkt. oekom Verlag München: 18 - 29 .
Elmer, M.; Schröder, J.; Bäucker, E.; Lange, M.; Clauder, L.; Bens, O.; Suckow, F.; Kätzel, R.; Bues, C.T.; Frommhold, H.; Sonntag, H.; Fischer, T.; Hüttl, R. (2009): OakChain: Eichen-Kiefern-Mischbestände im Spannungsfeld von Klimawandel, Waldumbau und internationalem Holzmarkt. Forst und Holz 64 (7/8): 26 - 29