11

From Equation 22.39

Sp;(n)=r2CDB2x2(n)Su(H, n)0^ I i f1(z1 )f1(z2)zalz21y(z1, z2, n) dz1 dz2

The square root of coherence g is determined from Equation 22.16, considering only the vertical correlation. Thus

Sp«(n1) = 1.22 x 1.32 x 562 x(0.45)2 x 18.8 x (3406r x 16,900 = 7.85 x 1010 N2/Hz

From Equations 22.41 and 22.42, the variance of resonant displacement at the top of the building is obtained as sD = f1(H)02d„ = Pn1 SP' (n1)

VfP^V^ x 1010)106 mm2

Nonresonant displacement

The variance of nonresonant displacement at the top of the building is determined from Equations 22.41 and 22.42 as sB = fi(H)sBqi =-^2 I Sp*(«) dn (ki) Jo

565 x 109 6

x 106 mm

Response to mean wind

From Equation 22.43, the mean generalized force

The generalized stiffness

1 V5.1V

Thus, the mean displacement

26:8 106

The peak factor gD for resonant response is determined from Equation 22.46 as 3.78. Using a peak factor of 3.5 for nonresonant response, the most probable maximum displacement is

The most probable maximum drift would be

0 0

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