TY - RPRT A1 - Siegl, Marco A1 - Ehrlich, Ingo A1 - Siegl, Marco A1 - Ehrlich, Ingo ED - Baier, Wolfgang T1 - Einfluss von Prozessparametern auf die Schmelzimprägnierung zur Herstellung von faserverstärkten Thermoplasten T2 - Forschung 2018 / Ostbayerische Technische Hochschule Regensburg N2 - Die Erforschung von faserverstärkten Kunststoffen (FVK) mit thermoplastischer Matrix ist aufgrund der Schweißeignung als Verbindungstechnologie, der thermischen Umformbarkeit, der Recyclebarkeit sowie der verkürzten Prozesszeiten im Vergleich zu den vorwiegend eingesetzten faserverstärkten Duroplasten erstrebenswert. Die Wechselwirkung zwischen den physikalischen, mechanischen und geometrischen Parametern erhöht den Komplexitätsgrad des Herstellungsprozesses. Ziel ist daher die Entwicklung einer Imprägniertechnik, die eine Fasertränkung mittels eines Thermoplastschmelzbades ermöglicht. Y1 - 2018 UR - https://doi.org/10.35096/othr/pub-1382 SP - 72 EP - 73 PB - VMK Verlag für Marketing & Kommunikation GmbH & Co. KG ER - TY - JOUR A1 - Kastenmeier, Andreas A1 - Siegl, Marco A1 - Ehrlich, Ingo A1 - Gebbeken, Norbert T1 - Review of elasto-static models for three-dimensional analysis of thick-walled anisotropic tubes JF - Journal of Composite Materials N2 - Most shell or beam models of anisotropic tubes under bending have no validity for thick-walled structures. As a result, the need to develop three-dimensional formulations which allow a change in the stress, strain and displacement distributions across the radial component arises. Basic formulations on three-dimensional anisotropic elasticity were made either stressor displacement-based by Lekhnitskii or Stroh on plates. Lekhnitskii also was the first to expand these analytical formulations to tubes under various loading conditions. This paper presents a review of the stress and strain analysis of tube models using three-dimensional anisotropic elasticity. The focus lies on layered structures, like fiber-reinforced plastics, under various bending loads, although the basic formulations and models regarding axisymmetric loads are briefly discussed. One section is also dedicated to the determination of an equivalent bending stiffness of tubes. KW - composite tube bending KW - layered structrues KW - anisotropy KW - Analytical modelling KW - elasticity Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-67521 N1 - Corresponding author: Andreas Kastenmeier PB - Sage ER - TY - JOUR A1 - Pongratz, Christian A1 - Tix, Janek A1 - Wolfrum, Johannes A1 - Gerke, Steffen A1 - Ehrlich, Ingo A1 - Brünig, Michael T1 - Test Setup for Investigating the Impact Behavior of Biaxially Prestressed Composite Laminates JF - Experimental Techniques N2 - Instrumented impact testing and compression-after-impact testing are important to adequately qualify material behavior and safely design composite structures. However, the stresses to which fiber-reinforced plastic components are typically subjected in practice are not considered in the impact test methods recommended in guidelines or standards. In this paper, a test setup for investigating the impact behavior of composite specimens under plane uniaxial and biaxial preloading is presented. For this purpose, a special test setup consisting of a biaxial testing machine and a specially designed drop-weight tower was developed. The design decisions were derived from existing guidelines and standards with the aim of inducing barely visible impact damage in laminated carbon fiber-reinforced plastic specimens. Several measurement systems have been integrated into the setup to allow comprehensive observation of the impact event and specimen behavior. A feasibility test was performed with biaxially prestressed carbon fiber-reinforced plastic specimens in comparison with unstressed reference tests. The compressive-tensile prestressing resulted in lower maximum contact forces, higher maximum deflections, higher residual deflections and a different damage pattern, which was investigated by light microscopic analysis. Finally, the functionality of the experimental setup is discussed, and the results seem to indicate that the test setup and parameters were properly chosen to investigate the effect of prestresses on the impacts behavior of composite structures, in particular for barely visible subsequent damages. KW - Mechanical Engineering KW - Mechanics of Materials KW - Faserverbundwerkstoff KW - Schlagprüfung Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-70355 SN - 0732-8818 N1 - Corresponding authors: Christian Pongratz und Ingo Ehrlich PB - Springer Nature ER - TY - JOUR A1 - Putzer, Michael A1 - Ehrlich, Ingo A1 - Rasmussen, John A1 - Gebbeken, Norbert A1 - Dendorfer, Sebastian T1 - Sensitivity of lumbar spine loading to anatomical parameters JF - Journal of Biomechanics N2 - Musculoskeletal simulations of lumbar spine loading rely on a geometrical representation of the anatomy. However, this data has an inherent inaccuracy. This study evaluates the influence of defined geometrical parameters on lumbar spine loading utilising five parametrised musculoskeletal lumbar spine models for four different postures. The influence of the dimensions of vertebral body, disc, posterior parts of the vertebrae as well as the curvature of the lumbar spine was studied. Additionally, simulations with combinations of selected parameters were conducted. Changes in L4/L5 resultant joint force were used as outcome variable. Variations of the vertebral body height, disc height, transverse process width and the curvature of the lumbar spine were the most influential. These parameters can be easily acquired from X-rays and should be used to morph a musculoskeletal lumbar spine model for subject-specific approaches with respect to bone geometry. Furthermore, the model was very sensitive to uncommon configurations and therefore, it is advised that stiffness properties of discs and ligaments should be individualised. KW - Musculoskeletal simulation KW - Lumbar spine KW - Parameter study KW - Vertebra KW - Wirbelsäule KW - Belastung KW - Simulation Y1 - 2015 U6 - https://doi.org/10.1016/j.jbiomech.2015.11.003 VL - 49 IS - 6 SP - 953 EP - 958 PB - Elsevier Science ER - TY - CHAP A1 - Putzer, Michael A1 - Penzkofer, Rainer A1 - Ehrlich, Ingo A1 - Rasmussen, John A1 - Gebbeken, Norbert A1 - Dendorfer, Sebastian T1 - Musculoskeletal simulations to investigate the influence of vertebral geometrical parameters on lumbar spine loading T2 - 7th World Congress of Biomechanics, Boston, United States, 04/07/14 -11/07/14 Y1 - 2014 ER - TY - CHAP A1 - Schmid, Vinzent A1 - Jungbauer, Bastian A1 - Romano, Marco A1 - Ehrlich, Ingo A1 - Gebbeken, Norbert ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - The influence of different types of fabrics on the fibre volume content and porosity in basalt fibre reinforced plastics T2 - 2nd Applied Research Conference 2012 - ARC 25./26. June 2012 N2 - High quality semi-finished products with reproducible properties of basaltic fibres are hardly available on the market. In order to examine the properties of basalt fibre reinforced plastics high quality specimens are necessary. The fibre volume content and the porosity of the produced specimen are used as the typical criteria to evaluate the achieved quality of the produced material. The effect of the geometrical properties of the different semi-finished products on the fibre volume contents is relatively small whereas the porosity content is considerably affected. Y1 - 2012 UR - https://www.researchgate.net/publication/268146522_The_influence_of_different_types_of_fabrics_on_the_fibre_volume_content_and_porosity_in_basalt_fibre_reinforced_plastics SP - 162 EP - 165 PB - Shaker ER - TY - CHAP A1 - Ladewig, Sven A1 - Siegl, Marco A1 - Ehrlich, Ingo ED - Mottok, Jürgen ED - Reichenberger, Marcus ED - Bogner, Werner T1 - Discussion about Viscosity Theories for Fibre-Reinforced Thermoplastics T2 - Applied Research Conference 2018 - ARC 2018, 10 July, Deggendorf N2 - The effect of process variables such as shear rate and temperature on the viscosity of polypropylene during the processing of thermoplastic based composites was investigated in this study. The melt impregnation is used in the process of continuous glass fibre reinforced thermoplastic composites. To develop a mathematical model for roving impregnation, it's essential to know about the viscous behaviour of the matrix system. Therefore, this paper will discuss rheological models to describe these phenomena, based on the gathered viscosity data from the partner laboratory at the University of West Bohemia in Pilsen. Y1 - 2018 SP - 144 EP - 149 PB - Pro Business Verlag CY - Berlin ER - TY - CHAP A1 - Steinmann, Sven A1 - Ehrlich, Ingo ED - Mottok, Jürgen ED - Reichenberger, Marcus ED - Stolle, Reinhard T1 - Investigation of transverse impact stress in fiber reinforced plastics under high-velocity impact and determination of the experimental procedure T2 - Applied Research Conference 2016 - ARC 2016, Augsburg, 24 June 2016 Y1 - 2016 PB - Pro Business Verlag CY - Berlin ER - TY - CHAP A1 - Schmid, Vinzent A1 - Jungbauer, Bastian A1 - Romano, Marco A1 - Ehrlich, Ingo A1 - Gebbeken, Norbert ED - Mottok, Jürgen ED - Ziemann, Olaf T1 - Diminution of mass of different types of fibre reinforcements due to thermal load T2 - Applied Research Conference 2012 - ARC 2012, 25./26. June 2012 Y1 - 2012 SP - 231 EP - 235 PB - Shaker ER - TY - CHAP A1 - Bohmann, T. A1 - Schlamp, Matthias A1 - Ehrlich, Ingo ED - Klippel, Clemens ED - Mottok, Jürgen ED - Reichenberger, Marcus T1 - Analysis of the Acoustic Emission Failure Frequencies of Glass Fiber Reinforced Composite Components T2 - Applied Research Conference 2017 - ARC, 7 July 2017, München Y1 - 2017 SP - 369 EP - 373 PB - Book-on-demand Verlag CY - Norderstedt ER -