A hybrid technique to extract cohesive fracture properties of elasto-plastic materials using inverse analysis and digital image correlation
Gain, Arun
Loading…
Permalink
https://hdl.handle.net/2142/16010
Description
Title
A hybrid technique to extract cohesive fracture properties of elasto-plastic materials using inverse analysis and digital image correlation
Author(s)
Gain, Arun
Issue Date
2010-05-18T18:56:02Z
Director of Research (if dissertation) or Advisor (if thesis)
Paulino, Glaucio H.
Department of Study
Civil & Environmental Eng
Discipline
Civil Engineering
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
M.S.
Degree Level
Thesis
Keyword(s)
cohesive zone model
inverse analysis
Park-Paulino-Roesler model (PPR)
Nelder-Mead scheme
Abstract
Current work utilizes cohesive zone modeling to study the fracture properties of
metals. This study proposes a hybrid technique experimental/numerical to extract
cohesive fracture properties of elasto-plastic material using inverse analysis and digital
image correlation. Two approaches are suggested - a shape optimization technique and a
parameter optimization for the PPR potential-based cohesive zone model. In shape
optimization approach, CZM is obtained by piecewise interpolation of the optimized
interpolation points whereas in parameter optimization for the PPR potential-based CZM,
the CZM is obtained by using the PPR model which utilized the parameters coming from
an optimization scheme. Unconstrained, derivative free Nelder-Mead scheme is used for
optimization purpose. The bulk material is modeled as plane-stress J2 plastic material.
The proposed schemes are verified for various plausible cases, such as different
displacement field data, various initial guess and noisy displacement field data. As a
proof of concept, both schemes are applied to Polymethyl Methacrylate (PMMA) quasistatic
crack growth experiment, which is modeled as elastic material, to substantiate its
utility. Near tip displacement field is obtained experimentally using DIC and used as
input to the optimization schemes. Computationally predicted global responses of the
PMMA specimen, using the CZMs extracted from the inverse analysis, shows good
agreement with the experimental global response.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
