Nonlinear Finite Element Analysis of Concrete Structures

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program and (2) attainment of insight into the structural behaviour
are maintained in the analysis of the considered structures.
It should also be emphasized that these structures all
represent very difficult cases to investigate by other theoretical
means and this benchmark-aspect should be borne in mind when
evaluating predictions versus experimental evidence. The structures
considered here are all loaded to their ultimate capacity,
the quantity of primary concern here.
The next section treats quadratic panels with isotropic and
orthogonal reinforcement loaded by tensile forces skewed to the
reinforcement. The analysis focuses on aspects of reinforcement
bar modelling and in particular or. simulation of lateral bar
stiffness.
In section 5.2, a thick-walled closure for a reactor pressure
vessel is considered. It represents a structure where large triaxial
compressive stresses as well as cracking are present. The
influence of different failure criteria and post-failure behaviours
is investigated.
Section 5.3 deals with the important cases of beams failing in
shear. Beams both with and without shear reinforcement are considered,
and of special interest are aggregate interlock, secondary
cracks, influence of the magnitude of tensile strength and
dowel action.
Finally, section 5.4 contains an analysis of a specific pull-out
test, the so-called LoK-test. The influence of the uniaxial compressive
strength, the ratio of tensile strength to compressive
strength, different failure criteria and post-failure behaviours
are investigated and special attention is given to the failure
mode.
5. J.. Panel
This first example of analysis of a concrete structure is an
introductory one dealing primarily with different aspects of re-