Civil Engineering Reference
In-Depth Information
REINFORCING STEEL
y
y
y
z
j
CONCRETE
z
confined
unconfined
x
z
Figure 9.8
Illustration of fiber beam-column element (Taucer
et al.
1991)
element, such as element flexibility and element displacements, are obtained from integrating
their sectional components along the element. The corresponding sectional components, such
as section flexibility and section forces, are calculated from summing the contributions of all
the fibers on the specific cross-section. The section force and deformation relation of RC fiber
section, the fiber element formulation, and the analysis procedures of the fiber model can be
found in the project report by Taucer
et al
. (1991).
9.4 2-D CSMM Model for Walls
As introduced previously, the CSMM is a rational model that can readily be applied to a plane
stress problem, such as reinforced concrete walls subject to reversed cyclic loading. Using this
model the coordinate systems, implementation and analysis procedures are presented below.
9.4.1 Coordinate Systems for Concrete Structures
Three Cartesian - coordinates,
x-y
, 1-2, and si-ti, are defined in the reinforced concrete
elements, as demonstrated in Figure 9.9. Coordinate
x-y
represents the local coordinate of the
elements. The coordinate 1-2 defines the principal stress directions of the applied stresses,
which have an angle
α
1
x
with respect to the
x-y
coordinate. Steel bars can be distributed in
different directions in the concrete. Coordinate si-ti shows the
i
ith direction of the reinforcing
steel bars, where the
i
th steel bars are located in the direction of axis si at an angle
α
ix
to the
x-y
coordinate.
