Wind Load to BS6399

PROJECT STRUCTURE CODES Reference

ELEMENT BS 6399:2 1997 Corrigendum No. 1

DESIGNED BY

Wind Load Calculation CHECKED BY

Calculations

REF 1/24/2017 Output

Building Wind Zone = 3 Since the building is a power station, it is categorized as a post-disaster Structure So basic 3-second gust wind speed

= 38 m/s

But the minimum 3 second wind speed to be taken for wind analysis = 40 m/s Hence Vbasic = 40 m/s which is in terms of three second gust speed

Vbasic = 40 m/s

Dynamic Classification BS6399:2-1997 Table 1 Figure 3

HB-Wind Loading by Nicholas J. Cook

BS6399:2-1997 Clause 2.2.2.1

Building Type Factor

=

kb

=

1 since this building is a framed structure with structural walls

Building Height above ground level = 20 m 6H0

Closest Dist. To Sea Closet Dis. in Town Hr He

>100 km

1 km

0.9 km

1 km

2.5 km

1 km

0.9 km

1 km

20 m 20 m

20 m 0.4xHr =0.4x20 = 8 m

20 m 20 m

20 m 20 m

Sb for eff. speed

1.77

1.73

1.9

1.9

Sb for convert 3 sec gust speed

1.62

1.78

1.78

1.78

Converted Vbasic in terms of houlry mean speed

40/1.62 = 24.7 m/s

40/1.78 = 22.5 m/s

40/1.78 = 22.5 m/s

40/1.78 = 22.5 m/s

Direc. Factor Sd

0.75

0.95

1

0.89

Site Spd. Vs

24.7x0.75x1.004x1x1 =18.6 m/s

21.5 m/s

22.6 m/s

20.1 m/s

Eff. Spd. Ve

18.6x1.77 =32.9 m/s

37.2

42.9

38.2

0.85 kPa

1.13 kPa

0.89 kPa

BS 6399: 2 Clau. 1.7.3.3. & Figure C2 Google Earth Clau. 1.7.3.3. Figure C4

Clau. 1.7.3.3. Table 4 HB-Wind Loading by Nicholas J. Cook HB-Wind Loading by Nicholas J. Cook Figure C3 & Table 3 of BS 6399:2 BS 6399:2 Clau 2.2.2.1. Clau 2.2.3.1. Clau 2.1.2.1.

Dyn 0.613x32.92x10-3 = 0.66 Pressure qs kPa

Dynamic Press"-ures

PROJECT STRUCTURE CODES Reference

ELEMENT BS 6399:2 1997 Corrigendum No. 1

DESIGNED BY

Wind Load Calculation CHECKED BY

Calculations

Pressure Coeffecient and Overall Wind Force

Table 5

Table 5

Figure 4

Figure 4 Figure 4

Clau. 2.1.3.1. , Clause 2.1.3.5. Figure 3 Clau. 2.1.3.6.

NE FACE

SE FACE

SW FACE

NW FACE

Cross wind breath :B

28.3 m

9.9 m

28.3 m

9.9 m

Inwind Depth D

9.9 m

28.3 m

9.9 m

28.3 m

D/H

0.5

1.42

0.5

1.42

Cpe windward

+0.85

+0.82

+0.85

0.82

Cpe leeward

-0.5

-0.5

-0.5

-0.5

Cpenet

+0.85-(-0.5) = 1.35

1.32

1.35

1.32

sqrt(9.92+202) =22.3 m

34.7 m

22.3 m

B

A

A

A

0.85

0.91

0.87

0.91

Diagonal sqrt(28.32+202) = 34.7 Dimension :a m Curve on Figure 4 Size eff, Factor Ca Loaded Area A Pnet=qxCpenetx CaxA

20x28.3 m2

20x9.9 m2

20x28.3 m2

20x9.9 m2

0.66x1.35x0.85x20x 28.3 = 434 kN

0.85x1.32x0.96x20x 9.9 = 202 kN

752 kN

211 kN

Cr

0.035

0.035

0.035

0.035

P overall

0.85x434x(1+0.035+ =382 kN

178 kN

662 kN

186 kN

382/6 = 64 kN

30 kN

110 kN

31 kN

P per floor dividing equally between 6 levels

Above Wind Forces are applied to relevant faces of the model in each level and the applied values can be found in Section 3.3.2.

REF 1/24/2017 Output