Wind Load Calculation

Wind speed -33m/sec

From Ground floor  to Slab level – 14.675m

SLAB LEVEL  to NEXT Slab level – 9.0 m

Horizontal support interval    – 1.55m

Height of the building = 27.725m say 28m

Length = 39.450m

Width = 22.195m

Dead load = self weight of beam

Wind load

WIND SPEED – 42M/SEC

Design Wind speed

Vz = Vb x K₁ x K₂Xk₃ xK₄

Vb= 33m/sqc

K₁ = 1     (Cl6.3.1- IS 875-3)

K₂ = 1.06 ( Terrain category -3)  ((Cl6.3.2.2- IS 875-3)

k₃ = 1.0 ( cl 6.3.3.1)

K₄ = 1.0 ( Cl- 6.3.4)

V_z = 33×1.06x1x1 = 34.98 m/sec

Wind pressure at height

P_z   = 0.6 V_Z²  = 0.6×34.98²  = 0.735Kn/sqm

Design wind pressure

P_d=K_d  K_a K_c P_z

K_d =  1.0  ( Cl- 7.2.1)

K_a =  1.0  ( Cl- 7.2.2)

K_c =  0.9 ( Cl- 7.3.3.13)

P_z = 0.735Kn/sqm

P_d  =  K_d  K_a K_c P_z

     =  0.662KN/sqm

WHICH IS HIGHER THAN 0.7P_Z SO CONSIDERED DESIGN WIND SPEED IS 0.662KN/SQM

Internal wind pressure

 = +0.2/-0.2

External wind pressure

L/w   = 39.45/22.195 = 1.78

h/w =  27.725/22.195 = 1.25

Critical co eff ( cl 7.3.3.1)

Pressure = +0.7

Suction =  -0.5    

Net wind co-eff

External to internal Pressure Co-eff  = +0.9

Internal to external pressure Co-eff= -0.7

Wind load on every vertical support

External to internal loads on the vertical support   = +0.9 x 1.55 x 0.662 = 0.923Kn/m 

Internal to external Loads on the vertical support   = -0.7 x 1.55 x 1.07  = 0.72 Kn/m

Reaction on support  positive  = (11.28×0.923)

                               = 10.42 KN( un factored)

                                 = 1.5×10.42 = 15.63KN( factored)

Reaction on support  Negative   = 11.28×0.72

                                = 8.12 KN  ( un factored)

                                 = 1.5×8.12 = 12.2KN( factored)