Pages From Asce 7-10 (3rd Print) 615l4x

Velocity Pressure Exposure Coefficients, Kh and Kz Table 29.3-1

Exposure

Height above ground level, z ft

(m)

0-15 20 25 30 40 50 60 70 80 90 100 120 140 160 180 200 250 300 350 400 450 500

(0-4.6) (6.1) (7.6) (9.1) (12.2) (15.2) (18) (21.3) (24.4) (27.4) (30.5) (36.6) (42.7) (48.8) (54.9) (61.0) (76.2) (91.4) (106.7) (121.9) (137.2) (152.4)

B

C

D

0.57 0.62 0.66 0.70 0.76 0.81 0.85 0.89 0.93 0.96 0.99 1.04 1.09 1.13 1.17 1.20 1.28 1.35 1.41 1.47 1.52 1.56

0.85 0.90 0.94 0.98 1.04 1.09 1.13 1.17 1.21 1.24 1.26 1.31 1.36 1.39 1.43 1.46 1.53 1.59 1.64 1.69 1.73 1.77

1.03 1.08 1.12 1.16 1.22 1.27 1.31 1.34 1.38 1.40 1.43 1.48 1.52 1.55 1.58 1.61 1.68 1.73 1.78 1.82 1.86 1.89

Notes: 1. The velocity pressure exposure coefficient Kz may be determined from the following formula: For 15 ft. ≤ z ≤ zg For z < 15 ft. 2/α Kz = 2.01 (15/zg)2/α Kz = 2.01 (z/zg) 2. α and zg are tabulated in Table 26.9.1. 3. Linear interpolation for intermediate values of height z is acceptable. 4. Exposure categories are defined in Section 26.7.

Minimum Design Loads for Buildings and Other Structures

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