Dynamic Behavior of Concrete: Constitutive Models - Dynamic Behavior of Concrete and Seismic Engineering - page 85

1 U

pp P p tr V P U = 1 [2.51]

3

0

ii) the deviatoric mechanism is defined by a threshold of plasticity in the plane

(p,q)

3

2 2

q s 3 J [2.52]

ij 2

2

The material's threshold curve depends on a damage variable D:

SS 1 D SD [2.53]

s f

where S S = threshold for the undamaged material and S f = threshold for the damaged
material (Figure 2.8).

Figure 2.21. “ARMOR” model, elastic field in the density-pressure plane
and flow threshold surface in the p-q plane (from [MAR 94])

2.6.6.2. Holmquist

- Reference: [HOL 93].

- Principle: spherical and deviatoric separation of parts, perfect plasticity and
damage.

- Application fields: high stresses, high strain rates and high pressure.

- Can model: compaction, damage.

- Cannot model: negative strain hardening.