o_19jdnovcg1eh21852116govv1lgra.pdf

PA-TOWER
PA-Tower
... to continue
• dynamic pressure for wind up to wind force beaufort
8 H< 8,0mq = 0,20 kN/m 2 ²
• wind on pay load
W = 1,3 x q x A [kN]
with A = surface exposed to the wind
• Wind on truss tower
w 1 = 0,25 x q [kN/m]
(estimated load for trusses with standard dimensions)
Example 2:
tower H = 6.0 m
pay load 500 kg (= 5.0kN)
eccentricity e = 0.5 m
surface exposed to wind A = 1.5 m²
Wind on tower of unperforated profiles
w 1 = 1,3 x b x q [kN/m]
with b = Towerwidth
For example a free standing tower without wind load limit
in wind zone 2:
• dynamic pressure
H< 10 mq = 0,46 kN/m 2²
• wind on the tower analogous to state of operation
w 2 = 0,25 x q bzw. w 2 = 1,3 x b x q
Wind on pay load is not taken into account because the
load is lowered from wind force beaufort 8.
As well as for the indoor use again the ratio tilting
moment - stability moment is decisive for the verification.
The tilting moment is:
For operation mode up to wind force 8:
Mk = P x e + W x H + w 1 x H 2 / 2
Out of operation:
Mk = w 2 x H 2 / 2
The stability moment is the same as for indoor use:
Ms = G x L/2
Here again the stability is proofed if:
Ms > v x Mk .
The safety factor for temporary buildings for wind loads is
v = 1,2.
For operation mode up to wind force 8 :
W = 1,3 x 0,20 kN/m² x 1,5m² = 0,39 kN
w1= 0,25 x 0,20 kN/m² = 0,05 kN/m
Mk = 5,0 kN x 0,5m+0,39kN x 6,0m + 0,05 kN/m x 6,0² / 2 = 5,74 kNm
for comparison:
tiliting moment at tower without pay load and without wind force limit:
Mk = 0,25 x 0,46 kN/m² x 6,0 ² / 2 = 2,07 kNm
ground area basement 1,5m x 1,5 m
self weight tower + basement 150 kg = 1,5 kN
stability moment Ms = (1,5kN + 5,0kN) x 1,5m / 2 = 4,875 kNm
required safety acc. EN 1381 = 1,2
Ms = 4,875 < 1,2 x Mk = 6,89 kNm
No verification => additional ballast necessary
Ms = erfG x 1,5m / 2 > 6,89 => erf G = 9,19 kN = 919 kg
present 150 kg + 500 kg => still necessary 269 kg
alternative : raising width of basement to 2,12 m
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