Nonlinear Finite Element Analysis of Concrete Structures

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Let us now consider the *~2 beam where shear re in forcessent is
present and let us illustrate the behaviour of the beam with
figures similar to figs. 4-7.
Fig. 8 shews the stress distribution at 63% loading. As previously
noted, loadings are expressed in relation to the predicted
failure load. Comparison with fig. 4 reveals that no
principal difference seems to exist for beams with and without
shear reinforcement.
Fig. 5.3-8: Isostress curves and directions of the principal
stresses in the A-2 beam. Loading = 63% of predicted
failure load. Quantities are in HPa.
Fig. 9 shows the development of the contour lines for the nonlinearity
index in per cent with increasing loading. A comparison
with fig. 5 again reveals no principal difference in the
behaviour of the two beams. For the A-2 beam also the region
adjacent to the load point is severely loaded; strain softening
initi -es here a little earlier than for the OA-2 beam namely
at 63% loading, i.e. for the stress distribution shown in fig. 8
and on fig. 9. At the failure load, this region is loaded far
into the post-failure region and just like the OA-2 beam this
situation is considered to be the primary reason for *he bear,
collapse.