Advertisement
ANCHORAGE
To make it easier to size the anchor points and ground bearing for the Escalib, the ground load
calculations and the forces at the anchor points are given for the various configurations.
Assumptions:
I - Wind action as in EN 1991-1-4:
- f = 0.23 and Cf = 2.73
- v p : Wind speed (km/h).
- q p : Peak wind pressure (daN/m²).
2 - Working load Q:
- 8 persons per Escalib module.
- Up to a maximum of 20 for the complete
stair tower.
- Stair tower not to be used for winds of over
65 km/h.
3 - Weight (P) of Escalib..
The results are presented at SLS. Wind
speeds are not weighted.
To calculate values for the ultimate limit
state, ULS:
1.5 x SLS
Anchor points:
Configuration 1:
d ≤ 20 cm
If "d" is greater than 20 cm,
wind bracing may be required to
reinforce the anchor system.
Configuration 2 requires special
calculations.
For a given direction, forces from
both ways must be taken into
account.
Anchorage height
1 module
Self-sup-
porting in
winds up to
120 km/h
Anchor
Stresses on the anchor points in configuration 1:
Shearing stresses (V):
Escalib
height
7-8 modules
5-6 modules
3-4 modules
1-2 modules
Pullout forces (T):
If a net (φ = 20%) covers
the Escalib, consider a
pressure q p multiplied
by 1.4.
Ground loads:
Ground loads P+Q (daN)
Number of modules
Max. load per foot
Total load
If the anchors used cannot withstand
the load calculated, increase the
number of anchor points.
2 mod-
3 mod-
4 mod-
5 mod-
ules
ules
ules
Self-sup-
Anchor points required every 3 modules for a wind speed
porting
less than 145 km/h (for higher speeds see table 1).
in winds
up to 72
km/h
900
800
Anchor
point density
700
Every 3 Every 2
600
modules modules
500
400
300
200
100
Vp : 90 100 110 120 130 140 150 160 170 180 190 km/h
q p : 38
550
450
350
250
150
50
Vp : 90 100 110 120 130 140 150 160 170 180 190 km/h
q p : 38
1
2
673
1050 1244 1339 1434 1529 1624 1719
1379 2355 2999 3379 3759 4139 4519 4899
6 mod-
7 mod-
8 mod-
ules
ules
ules
ules
Cisaillement : V
Arrachement
47
57
68
80
93 106 121 137 153 171 daN/m²
47
57
68
80
93 106 121 137 153 171 daN/m²
3
4
5
6
WWW.COMBISAFE.COM
module 8
module 7
module 6
module 5
module 4
module 3
module 2
module 1
Base
de po
7
8
12
Advertisement
