Please cite this article in press as: E. Kishta, et al., Strong discontinuity analysis of a class of anisotropic continuum damage constitutive
models – Part II: Concrete material application, Mech. Re. Commun. (2017), http://dx.doi.org/10.1016/j.mechrescom.2017.03.004
ARTICLE IN PRESS
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MRC-3155; No. of Pages 5
Mechanics Research Communications xxx (2017) xxx–xxx
Contents lists available at ScienceDirect
Mechanics Research Communications
journal h om epa ge: www.elsevier.com/locate/mechrescom
Strong discontinuity analysis of a class of anisotropic continuum
damage constitutive models – Part II: Concrete material application
Ejona Kishta
a,b
, Benjamin Richard
a,∗
, Cédric Giry
b
, Frédéric Ragueneau
b
a
DEN-Service d’études mécaniques et thermiques (SEMT), CEA, Université Paris-Saclay, F-91191, Gif-sur-Yvette, France
b
LMT, ENS Cachan, CNRS, Université Paris-Saclay, 61 avenue du Président Wilson, F-94230 Cachan, France
a r t i c l e i n f o
Article history:
Received 24 October 2016
Accepted 26 March 2017
Available online xxx
MSC:
00-01
99-00
Keywords:
Discontinuity
Failure
Damage
Anisotropy
Willam’s test
a b s t r a c t
On the basis of the strong discontinuity analysis, a discrete model expressed in terms of traction vector-
displacement jump has been constructed from a continuous model expressed in terms of stress–strain
law. In the first part of the paper, this approach has been extended to a class of anisotropic continuum
damage constitutive models [1]. In this second part of the paper, the proposed class of discrete anisotropic
damage constitutive models is particularized. More precisely, a micromechanical-based anisotropic dam-
age constitutive model is derived. This model accounts in a natural manner for particular crack families
orientation. The aims of this paper are (i) to illustrate the capabilities of the proposed discrete enhanced
model in reproducing the induced anisotropy appearing in quasi-brittle materials when cracking and
(ii) to assess the numerical robustness of the time integration scheme. For this purpose, two numerical
examples at the material point level are exposed after a brief presentation of the time integration scheme.
The correspondence between the continuous and the discrete model as well as the induced anisotropy
features are emphasized.
© 2017 Elsevier Ltd. All rights reserved.
1. Introduction
In the first part of this paper, it was shown that the strong discon-
tinuity kinematics enhancement leads naturally to the definition
of a discrete constitutive model, expressed in terms of traction
vector-displacement jump, for a class of anisotropic continuum
damage based constitutive models [1]. This framework was already
well-established for isotropic damage and plasticity model [2,3].
The discrete framework is built considering the traction continu-
ity condition and regularization of the hardening parameter. These
considerations allow for the kinematic compatibility between the
continuum model, expressed in terms of stress–strain relation, and
the strong discontinuity kinematics. For an easier reading, the dis-
crete constitutive equations of the proposed class of anisotropic
damage models are summarized hereafter (see Eqs. (1a)–(1f)).
State potential
¯
=
1
2
t
0
· [u ] −
n
i=1
¯
i
g
i
(([u ] ⊗ n )
s
) (1a)
∗
Corresponding author.
E-mail address: Benjamin.Richard@cea.fr (B. Richard).
Traction vector
t =
∂
¯
∂[u ]
= t
0
−
n
i=1
¯
i
dg
i
d[u ]
(([u ] ⊗ n )
s
) (1b)
Thermodynamic forces
¯
F
¯
i
= −
∂
¯
∂ ¯
i
= g
i
(([u ] ⊗ n )
s
) (1c)
Threshold surface
¯
i
(
¯
F
i
,
¯
Z
i
) =
¯
F
i
−
¯
Z
i
(1d)
Flow rules
˙
¯
i
=
˙
¯
i
∂
¯
i
∂
¯
F
¯
i
=
˙
¯
i
;
˙
¯ z
i
=
˙
¯
i
∂
¯
i
∂
¯
Z
i
= −
˙
¯
i
(1e)
Loading/unloading conditions
˙
¯
i
≥ 0;
¯
¯
i
≤ 0;
˙
¯
i
¯
¯
i
= 0 (1f)
In this second part, the discrete framework is applied to a
specific micromechanical-based anisotropic damage model. This
model is chosen because it describes the anisotropic character
of concrete-like materials illustrated by different oriented crack
families. Furthermore, this framework is useful for future develop-
ments on reinforced concrete structures characterized by normal
http://dx.doi.org/10.1016/j.mechrescom.2017.03.004
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