Prof. Dr. Ingo Burgert

Transcription

1 Leiter der Bachelor- Prof. Dr. Ingo Burgert Institut: Fachbereich: IfB CE Anzahl Themen: 6 Themen direkt auf der Website der Professur/des Instituts veröffentlicht Link:

2 Fire tests on mineralized wood for construction Dr. Huizhang Guo, Prof. Dr. Ingo Burgert Wood is a combustible material. Fire-safety is one of the main concerns in wood buildings. In recent research, we have developed a facile method to mineralize wood with phosphate-based minerals. The mineralized wood is provided with significantly improved fire resistance regarding ignition and char formation in a fire scenario. In this project, the students will perform wood mineralization at ETH and assess the fire-resistant capacity of the mineralized wood at Empa St. Gallen. To be more specific, the student will carry out Limited Oxygen Index (LOI) measurements according to ASTM D2863 standard to determine the minimum oxygen concentration that can sustain flaming of wood after removal of an ignition source. The student will also carry out Cone Calorimetry measurements according to the ISO :2002 norm to assess the heat release rate and smoke production rate for specimens exposed into an external igniter with a constant heat flux. Further bench-scale materials characterization includes Thermogravimetric Analysis (TGA), Pyrolysis Combustion Flow Calorimeter (PCFC) and thermal conductivity. Anzahl: 2 2

3 The effect of humidity on the energy conversion of wood based nanogenerators Dr. Huizhang Guo, Mr. Jianguo Sun, Prof. Dr. Ingo Burgert Nanogenerators based on wood materials for energy conversion have attracted increasing attention, since wood is an abundant, renewable and biodegradable material. However, wood is a very humidity sensitive material, which could be a challenge for such applications. We have worked on densified wood via a hot-pressing process, which endows the wood nanogenerator with excellent triboelectric output performance. However, the moisture effect on such an application is unknown. In this project, we are going to study the output performance of wood generators under different humidity conditions. The wood nanogenerator will work under successive contacting and separating between the densified wood surface and another material such as Teflon. The knowledge gained in this project is valuable to push forward the application of wood materials in energy conversion. 3

4 Micro-mechanical characterization of delignified wood Dr. Falk Wittel, Dr. Tobias Keplinger, Marion Frey, Prof. Dr. Ingo Burgert Densified Cellulose Composites based on wood are a novel material concept, which unifies delignification and densification of wood resulting in a compacted cellulose material for high performance applications. The hierarchical structure and directionality of wood is preserved during the process and the obtained material is more homogenous compared to wood combining high strength with high toughness. For a comprehensive understanding of the macroscopic properties and performance of delignified wood a detailed analysis of the mechanics on a cell level is needed. In a first step, wood cubes with different lignin content using varying delignification chemistries will be prepared and characterized by Infrared spectroscopy and the weight loss determined. From the prepared cubes, individual fibers will be isolated and tested by single fiber tests and the stressstrain curves will be analyzed. In addition to single fiber tests, individual years rings will be prepared from the delignified wood cubes and tested by compression testing. 4

5 Characterization of the bonding performance of combined one-component polyurethane adhesives and primer systems Dr. Tobias Keplinger, Dr. Maria Adobes-Vidal, Prof. Dr. Ingo Burgert Cross-laminated timber (CLT) panels are used as loadbearing wall and floor elements and have become one of the most popular and dominant products for modern timber buildings. CLT panels are produced from wood boards, which are stacked crosswise and glued together over their entire surface. Thus, the mechanical performance of CLT is closely linked to the bonding performance of the adhesives employed. For the bonding of load-bearing timber elements onecomponent polyurethane (1C-PUR) adhesives are being increasingly used. Surfactants can be used as primer systems in combination with 1C-PUR adhesives to improve the bonding performance, but very little is known about the wood-primer-adhesive interaction mechanism or the influence of several parameters in the gluing process such as primer concentration, primer quantity and primer activation time. The project focuses in the investigation of the above-mentioned parameters in both hardwood and softwood by means of tensile shear tests. 5

6 Simulation of the densification process of delignified cellulose scaffolds Dr. Falk Wittel, Dr. Tobias Keplinger, Marion Frey, Prof. Dr. Ingo Burgert Densified Cellulose Composites based on wood are a novel material concept, which unifies delignification and densification of wood resulting in a compacted cellulose material for high performance applications. The hierarchical structure and directionality of wood is preserved during the process and the obtained material is more homogenous compared to wood combining high strength with high toughness. For a detailed understanding of the densification a simulation of the project is envisaged. Within your project, you will apply a particle method called Material Point Method (MPM) to simulate the process of compaction of de-lignified wood sections. You will set up various systems based on images of wooden micro-structure and calculate the dynamic process of compaction under various scenarios. 6

7 Design and analysis of 4D wood structures M.Rüggeberg, F.Wittel We use the term 4D to refer to the simple production of initially flat (2D) structures that can transform their shape at different times. When designing with wood, one makes use of anisotropic moisture responses and/or shapememory effects with frozen strains to trigger out-of plane deformations. Within your project you will elaborate 3D shape evolutions with a focus on cupula structures using beech wood. You will scout for promising configurations using the Finite Element software ABAQUS, fabricate prototypes, and record their shape change into a 3D structure. The project work can be made in English or German. Knowledge in Abaqus or other FEM software is helpful. 7