Table 29.2 Length of tie rod
Fig. 29.1
d
Bt
a
L
A
Upper rebar layer
Lower rebar layer
Tie rod DW
Single anchor DW
Planing cap
The exact length of the tie rods
DW when using single/double
anchors depends on the floor
slab thickness d
Bt
(Fig. 29.1) and
is calculated using the formula
on the right. For the exact length
of the tie rods DW in the dif-
ferent slab thicknesses refer to
Table 29.2.
Depending on the slab thickness,
the maximum installation depth
of the anchors and any addi-
tional rebaring measures required
are to be clarified with the struc-
tural engineer taking corrosion
protection requirements into
consideration.
Note
Æ
The tie rod lengths specified
in Table 29.2 apply when the
planing cap is installed. If planing
cap DW 26.5 is used, the tie rod
must be 1 cm longer.
Æ
Longer tie rods are required
if planing caps are not installed.
Length of the tie rod when using the single/double anchor:
L
A
= 2 x (d
Bt
- a - 6.5)
L
A
= length of tie rod
d
Bt
= thickness of component/slab
a = distance between lower edge of component to lower edge of slab
Anchoring – Installing single/double anchors
5 (3.5)
Single/double anchor
Thickness of component/slab in cm
35
40
45
50
55
60
65
Length of tie rod L
A
(for a concrete
thickness of at least 20 mm and use
of a planing cap)
35
42
49
56
65
72
79
The minimum length of the tie rod is 50 cm when anchoring the STB 450 (see page STB-25). The
part/slab must thus have a thickness of at least 50 cm.
Use of the planing cap DW 26.5 = length of tie rod L
A
+ 1 cm.
The dimension in brackets applies to the
use of planing cap DW 26.5.
STB-29
Technical Instruction Manual / Status November 2019
STB
Support frame
