Issue 39

M. Romano et alii, Frattura ed Integrità Strutturale, 39 (2016) 226-247; DOI: 10.3221/IGF-ESIS.39.22 226 Parametric characterization of a mesomechanic kinematic caused by ondulation in fabric reinforced composites: analytical and numerical investigations Marco Romano, Ingo Ehrlich Ostbayerische Technische Hochschule Regensburg, Department of Mechanical Engineering, Laboratory of Composite Technology, Galgenbergstrasse 30, 93053 Regensburg, Germany Norbert Gebbeken University of the Bundeswehr Munich, Department of Civil Engineering and Environmental Sciences, Institute of Engineering Mechanics and Structural Analysis, Werner-Heisenberg-Weg 39, 85577 Neubiberg, Germany A BSTRACT . A parametric characterization of a mesomechanic kinematic caused by ondulation in fabric reinforced composites is investigated by analytical and numerical investigations. Due to the definition of plain representative sequences of balanced plain-weave fabric reinforced single layers based on sines the variable geometric parameters are the amplitude and the length of the ondulation. The mesomechanic kinematic can be observed in both the analytic model and the FE-analyses. The analytic model yields hyperbolic correlations due to the strongly simplifying presumptions that neglect elasticity. In contrast the FE-analyses yield linear correlations in much smaller amounts due to the consideration of elastic parts, yet distinctly. K EYWORDS . Fiber reinforced plastics; Mesomechanic scale; Fabric reinforced layer; Ondulation. Citation: Romano, M., Ehrlich, I., Gebbeken, N., Parametric characterization of a mesomechanic kinematic caused by ondulation in fabric reinforced composites: analytical and numerical investigations, Frattura ed Integrità Strutturale, 39 (2017) 226-247. Received: 29.09.2016 Accepted: 02.12.2016 Published: 01.01.2017 Copyright: © 2017 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. I NTRODUCTION owadays the use of fiber reinforced plastics become indispensable in many areas in industry. The feature of high stiffness and strength which simultaneously combine low mass allows new design approaches for weight loss, which leads to energy savings, for example in the automotive and aircraft industry. Simplified theoretical approaches for fiber reinforced plastics often presume a layup of only unidirectionally reinforced single layers. As a first approach in applied engineering the structural mechanic properties can analytically be determined by the use of so-called micromechanical homogenization theories. These are usually based on the single components’ properties, namely matrix and fiber. However, different kinds of fabrics are often applied as reinforcements in the layup of structural parts. In this case homogenization theories reach their limit. The reason therefore is that the mesomechanic N