Dynamic Behavior of Concrete: Constitutive Models - Dynamic Behavior of Concrete and Seismic Engineering - page 90

Figure 2.25. Relative displacement-normal load answer of a bonding between
two EDs and strength field limit (from [DON 98])
2.6.8.3. “LMGC” type
- Reference: [MOR 96].
- Type: “dynamic contact”.
The directing idea of this model is dealing separately with the elasticity of the
medium and the adhesive contact laws where damage can appear. The laws linking
the elements are of the graph type and describe the contact physical behavior.
Between two elements, two physical principles exist: the existence of contact that is
described using a Signorini condition, and the potential friction between elements.
To this law, a new law is added to build a cohesive medium, namely adherence. Two
media stand out, the micro-medium between discrete elements respecting the
adhesive friction contact laws, and the macro-medium which describes the elastic
continuous medium governed by the first principle of dynamics and the elements'
elastic (or viscoelastic) strain laws.
2.7. Conclusion
2.7.1. Main features of the models
Most models are constructed within an elastoplastic framework, with a criterion
determined by the first stress invariant. Taking the loading field into consideration,
models generally include:
- a plastic flow due to shear;
- a plastic volume strain due to compaction;
- scalar damage due to cracking (usually).