- Title Information
- Title
- Large-deformation, viscoelastic constitutive modeling of elastomeric foams
- Name:
Personal
- Name Part
- Li, Xiuqi
- Role
- Role Term:
Text
- creator
- Name:
Personal
- Name Part
- Henann, David
- Role
- Role Term:
Text
- Advisor
- Name:
Personal
- Name Part
- Franck, Christian
- Role
- Role Term:
Text
- Reader
- Name:
Personal
- Name Part
- Srivastava, Vikas
- Role
- Role Term:
Text
- Reader
- Name:
Corporate
- Name Part
- Brown University. Engineering: Mechanics of Solids
- Role
- Role Term:
Text
- sponsor
- Origin Information
- Copyright Date
- 2021
- Physical Description
- Extent
- , None p.
- digitalOrigin
- born digital
- Note:
thesis
- Thesis (Ph. D.)--Brown University, 2021
- Genre (aat)
- theses
- Abstract
- Elastomeric foams are widely used for impact protection due to their ability to undergo
large, reversible deformations and absorb large amounts of energy. A predictive model of
their time-dependent, large-deformation mechanical behavior is needed for use in design.
This thesis addresses several problems related to the constitutive modeling of elastomeric
foams:
• At quasi-static strain rates, the material response in simple compression/tension is
highly nonlinear and shows substantial asymmetry between tension and compression.
The response in compression is particularly complex. The response is initially linear,
but as the axial strain magnitude increases, the response gradually transitions into a
“plateau” in which both the axial stress and the lateral strain vary minimally as the
axial strain magnitude increases. We propose a phenomenological, isotropic, finitedeformation, hyperelastic constitutive model based on invariants of the logarithmic,
Hencky strain that is able to capture the material response. A systematic procedure
for material parameter estimation is provided.
• At higher strain rates, due to the viscoelasticity of the matrix, many elastomeric foams
display a highly dissipative, time-dependent mechanical response, manifesting in
rate-dependence and hysteresis under reversed loading. We propose a viscoelastic
model based on a multi-mechanism, multiplicative-decomposition based strategy. The
model consists of a time-independent, hyperelastic contribution and several timedependent, viscoelastic contributions that employ the multiplicative decomposition of
the deformation gradient into non-equilibrium elastic and viscous parts.
• Different foam materials exhibit different rate-dependent behavior due to their porous
structures and matrix material types. The phenomenological modeling framework
proposed in this thesis is able to accommodate this by utilizing a flexible flow rule and a
flexible non-equilibrium free energy density function for the viscoelastic contributions.
We show that the model framework may be applied to both open-cell and closed-cell
elastomeric foams and validate the predictive capability of the calibrated model for
several materials in multiple cases that involve inhomogeneous deformation.
- Subject (fast)
(authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/01167809")
- Topic
- Viscoelastic materials
- Subject
- Topic
- Constitutive Modeling
- Subject
- Topic
- hyperelastic
- Subject
- Topic
- elastomeric foams
- Language
- Language Term (ISO639-2B)
- English
- Record Information
- Record Content Source (marcorg)
- RPB
- Record Creation Date
(encoding="iso8601")
- 20210607
- Type of Resource (primo)
- dissertations