consideration the influence of the longitudinal
deformation of the columns on the main bearing
system. Deformations of columns due to high
compression have to deal
with elastic deforma-
tion creeping and shrinkage of the concrete.
Some deformation is eliminated by floor slab lev-
elling, some has to be predicted by calculation. It
is also necessary to take into the consideration
the decreasing normal forces in the columns due
to the decreasing effect of the live load depend-
ing on the number of the floors above. Influence
of the settlement in the core area,
which is high-
er than settlement in the perimeter columns, also
plays a role in the designing of the bearing sys-
tem. For seismic response calculation, different
sub grade properties have to be used (stiffness or
resistance of the soil in the case of the dynamic
loads is higher).
At least two models have to be
calculated for one proportioning.
With ESA-Prima Win
we have the possibility to
make many calculations in real time.
Foundation slab design and calculation
The internal force and the calculation of the
foundation slab on the 3D
model for global
structure analysis was used here. The centre of
the gravity forces of the building was not close to
the centre of the contact area, as resulting from
the basement layout. For this reason cantilever
parts were designed.
Now the centre of the gravity force comes close
to the gravity centre of the resisting contact area.
The proportioning
was performed in the same
model.
Columns calculation
Columns are calculated in a separate calculation.
Normal forces are adopted from global structural
analysis. Bending
moments are adopted from
floor slab calculation. For each type of column, a
calculation is performed and influence due to live
load is taken into consideration.
Floor slab calculation
Floor slabs are calculated in a separate
model,
punching shear and connection to the core walls
is taken into account. In this model also bending
moments in the columns are calculated.
Around
the columns a more dense mesh is used.
On one
side, there are decreased bending moments in
the columns, and on the opposite side, there are
increased positive moments in the floor slab. The
proportioning of the slab in the columns is done
based on sections and the reinforcement is dis-
tributed accordingly.
Conclusion
In order to obtain a solution of such a demand-
ing structure, a very effective program for the cal-
culation of internal forces calculation is needed.
It must be able to prepare the structural
model
and to offer various possibilities to check the
results. The incorporation of the proportioning in
one package is also big advantage. ESA-Prima
Win fulfils these requirements.
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