Use of user subroutines in abaqus

Title:Finite element simulations of a composite mesh structureOther Titles:Finite Element Simulations of a Braided Composite StructureLanguage:GermanAuthors:Jordanov, BoriszQualification level:DiplomaAdvisor:Pettermann, HeinzAssisting Advisor:Kaul, JanIssue Date:2019Number of Pages:75Qualification level:DiplomaAbstract:
The topic of the present diploma thesis deals with the finite element simulation of a fabric laminate, which is a variant of fiber reinforced plastics (FRP). Since this type of material is already widely used today, it is crucial to study the behavior of FRP. The Abq-Ply-Fabric material model, which is integrated into the commercial finite element program Abaqus, is suitable for the calculation of fabric laminates with homogenized layers. However, it is important to simulate a detailed tissue structure for a detailed examination of braided structures. The aim of this work is to answer the following question. Can Abaqus / Explicit be used with the Abq-Ply-Fabric material model to calculate a composite mesh structure with plasticity? The structure is modeled in detail, so one looks at the individual fiber bundles and matrix pockets based on the mesoscopic scale length. The fiber bundles are modeled as transversely isotropic unidirectional layers (UD layers) with damage and plasticity using Abq ply fabric, and the matrix pockets as isotropic material with Drucker-Prague plasticity. The elasto-plastic failure of FRP serves as the basic basis for understanding the behavior of the fiber-reinforced UD layers. The damage mechanics provide information about the behavior after the damage has been initiated. The finite element simulations are suitable for displaying the behavior of the tissue in a more visible or easier way to evaluate than with an experiment in reality. The latter is hardly or not at all possible due to the complex structure of the fiber-reinforced plastics. The material model Abq-Ply-Fabric involves the use of the explicit time integration of Abaqus / Explicit. Mass scaling is used to reduce the computing time. The simulations were carried out using Abaqus / Explicit 2018 (Dassault Systemes SIMULIA Corp. 1301 Atwood Avenue, Suite 101W Johnston, RI 02919, USA). With the results it can be determined that the material model Abq-Ply-Fabric can represent the correct behavior of the detailed composite mesh structure - from individual UD fiber bundles and matrix pockets. This means that the tissue structures can be determined more precisely and, accordingly, more efficiently adapted to the requirements.

The topic of this diploma thesis deals with the finite element simulation of a fabric laminate, which is a variant of fiber reinforced polymers (FRP). Since this type of material is already widely used today, the examination of the behavior of the FRP is crucial. The material model Abq-Ply-Fabric, which is built in the commercial finite element program Abaqus, is suitable for laminates with homogenized fabric plies. Nevertheless, the simulation of a detailed fabric structure is important to be able to study the behavior of the fabric laminates more extensively. The aim of this thesis is to answer the following question. Can Abaqus / Explicit be used with the material model Abq-Ply-Fabric for the calculation of a composite braid structure in consideration of plasticity? The structure is modeled in detail, so the individual fiber bundles (tows) and matrix pockets are considered, which represents mesoscopic length scale. The fiber bundles are modeled as transversally isotropic unidirectional layers (UD layers) with damage using Abq-Ply-Fabric, and the matrix pockets as isotropic material with Drucker-Prager plasticity. The elasto-plastic failure modes of the FRP serve as a basic element for understanding the behavior of the fiber-reinforced UD layers. The damage mechanics gives information about the behavior after the damage initiation. The finite element simulations are suitable for visualizing the behavior of the fabric structure, which is hardly or not at all possible with a test in reality because of the complex structure of the fiber reinforced plastics (FRP). The material model Abq-Ply-Fabric implies the use of explicit time integration of Abaqus / Explicit. In order to obtain a smaller computing time, mass scaling is used. The simulations were performed using Abaqus 2018 (Dassault Systemes SIMULIA Corp. 1301 Atwood Avenue, Suite 101W Johnston, RI 02919, USA). According to the results, it can be concluded, that the material model Abq-Ply-Fabric predicts the correct behavior of the detailed composite braid structure consisting of individual tows and matrix pockets. This means that the fabric structures can be more accurately calculated and more efficiently adapted to the requirements.
Keywords:non-linear finite element method; Braid composite; Component simulation; Embedding approach; Multiscale model; Plasticity; damage
nonlinear finite element method; braided composite; structural simulation; embedding approach; multiscale model; plasticity; damage
URI:https://resolver.obvsg.at/urn:nbn:at:at-ubtuw:1-128937
http://hdl.handle.net/20.500.12708/4438Library ID:AC15474239Organization:E317 - Institute for Lightweight Design and Structural BiomechanicsPublication Type:Thesis
University thesisAppears in Collections:Thesis