Models for Simulating the Seismic Response of Concrete Structures - Dynamic Behavior of Concrete and Seismic Engineering - page 235

Figure 7.1. Overall models of shear and masonry in filled walls
7.2.2. Semi-global modeling
Multi-fiber and multi-layer models are examples of semi-global models: they
rely on beam elements and cover the conventional laws of beam theory - the
hypothesis of plane sections that remain plane for instance. Here, the inner stresses
are calculated from uniaxial laws that reproduce the behavior of each material
(concrete, steel, etc.) instead of empirical laws. Such an approach by of this
“simplified method” frames results in generating problems of moderate size and
with a quality standard that is respectable when compared to those obtained using
conventional 2D or 3D finite element calculations, particularly if the discretization,
the behavior models and the boundary conditions are well-defined.
Multi-layer discretization is well suited to dealing with plane problems involving
slender structures. Later, among the applications, we will present an example
illustrating “multi-layer” elements and including a damage model that will be
described further in section 7.4.2. These elements include two nodes and consist of
superimposed layers with non-linear behavior, specialized according to whether they
include reinforcements or not (Figure 7.2). The Navier-Bernouilli hypothesis on
cross-sections attributes a uniaxial behavior to the layers [MAZ 98]. As far as layers