57
Z
o,d
Q
o,d
Z
z,d
h
s
h
B
D
u,d
CB 240 Climbing Formwork
Instructions for Assembly and Use – Standard Configuration
C1 Planning and Work Preparation
Platform Dimensioning
Influence Factors for Dimensioning
b Width of influence of the bracket
h
S
Formwork height
Formwork weight max. 60 kg/m²
h
B
Concreting height
z Operating height above ground
q
κ
Reduced wind flow pressure
κ
Service life factor
(up to 24 months
κ
= 0.7)
q(z) Dynamic wind pressure
depending on the working height
and the reference wind pressure
according to the wind zone
Z
o,d
Design tensile force on the
bracket anchoring
Q
o,d
Vertical design shear force on the
bracket anchoring
D
u,d
Design compressive force to be
supported on the base of the
bracket
Z
z,d
Design tensile force in the wind
bracing
Determining the wind loads accor-
ding to DIN EN 1991-4 and DIN EN
12812
The dynamic wind pressure q(z) is deter-
mined from the operating height z, wind
load zone WZ and location, and reduced
by a service life factor
κ
.
q
κ
=
κ ⋅
q(z)
According to DIN EN 12812,
κ
= 0.7 can
be assumed for a service life up to 24
months.
Corner Platforms
In the corner area, it is normally necessary
to facilitate access around the corner of
the structure. For this purpose, corner
platforms are formed. In so doing, a
maximum overhang of 80 cm is allowed
on the concreting platform. No overhang
is allowed for the formwork nor finishing
platform. For larger overhangs, the width
of influence of the corner bracket is to
be increased accordingly or a separate
statistical proof is to be carried out.
Verification of the Platforms
The platform decking and platform
beams can be verified using the tables,
see C1 Platform Decking.
The length of the cantilevered area of
the platform beams must not be larger
than half the distance of the two brackets
of one unit.
In those cases where cantilevers are
longer, the main beams together with
their fastenings are to be verified by the
contractor and additionally secured
against lifting.
Verification of the Guardrails
Verification of the guardrails for the
concreting and intermediate platforms is
made in accordance with the respective
national regulations.
Verification of the guardrails for the
working platform and finishing platform
can be done with the help of the tables,
see C1 Rear and Side Protection.
Actual Width of Influence
The actual width of influence is deter-
mined with the help of the strongback
arrangement and taking into account the
formwork cantilever, and compared with
the permissible width of influence.
Permissible Width of Influence
The permissible width of influence for
the formwork height h
S
and the actual
service duration and height-dependent
dynamic wind pressure q
κ
is to be taken
from the CB 240 dimensioning informa-
tion. The different wind loads in the
standard and transition areas as well as
in the corners of the buildings are to be
taken into account. This results in diffe-
rent permissible widths of influence for
these areas.
Reaction Forces
The design values of the reaction forces
for the permissible width of influence
are to be taken from the separate
CB 240 design information and are to
be linearly interpolated for the formwork
height h
s
and the assumed dynamic
wind pressure q
κ
. These values must be
converted with the help of the given for-
mulae for the actual width of influence.
The reaction forces Z
o
und Q
o
on the
climbing anchor are to be verified sepa-
rately with the help of the interaction
charts for each load case.
AuV CB 240 EX.indb 57
29.06.16 09:45
