Consistent Forming Limit Diagram for the Fracture Criteria of Shell Elements in Structural Analyses

Authors:

  • Geng Sheng Wang

Publish date: 2022-09-30

Report number: FOI-R--5329--SE

Pages: 39

Written in: English

Keywords:

  • Aged A36
  • Mesh size effect
  • Shell element
  • Fracture model
  • Strength model
  • Hosford-Coulomb
  • Johnson-Cook
  • Forming Limit Diagram

Abstract

This work aims to establish methodology to determine consistent strength and failure models for numerical simulations of complex large structures under dynamic loading conditions. The focus is to provide reasonable material models suitable for numerical analyses using the structural shell element that is among the most effective options in the simulations of weapon effects on lightweight structures. For dynamics applications, the intrinsic as well as mesh size regularization are considered in the model. The models are based on the tests at shear, tension, and plane strain conditions with dedicated specimens. Measurements based on the digital image correlation (DIC) technique are used to determine the relationship between the load and deformation. In addition to the development of methodology, an aged steel is characterized regarding its yield and fracture behavior. For this steel, the material model includes the mesh size regularization for numerical simulations with shell elements.