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WEST 1624 Grove Street (425)347-8998 <br /> COAST _ <br /> STRUCTURAL Suite D2 wcse.net <br /> ENGINEERING,INCMarysville,WA 98270 <br /> . <br /> ASCE 7-10 Chapter 27 Directional Procedure Wind Load Design Procedure: Enclosed Buildings <br /> Velocity Pressure Coefficients, Kh and Kz <br /> Design Parameters: Table 27.3-1 qz = 0.00256 * Kz* Kzt * Kd *V^2 = <br /> Exposure <br /> V= 110 mph (Figure 26.5-1A) Height, z qz <br /> Exposure: B ft B C D psf <br /> Kd = 0.85 ASCE table 26.6-1 _ 0-15 0.57 0.85 1.03 15.0 <br /> Kzt= 1 Topographic factor 20 0.62 0.90 1.08 16.3 <br /> RC = 2 Risk Category 1.5-2 25 0.66 0.94 1.12 17.4 <br /> Velocity is based upon Risk Catergory, and 30 0.70 0.98 1.16 18.4 <br /> there is no longer an importance wind factor. 40 0.76 1.04 1.22 20.0 <br /> G = 0.85 Gust Factor 6.5.8 50 0.81 1.09 1.27 21.3 <br /> Gcpi = 0.18 (+/-figure 6-5) 60 0.85 1.13 1.31 22.4 <br /> h = 15 mean roof height(ft, h) 70 0.89 1.17 1.34 23.4 <br /> 15 snap to nearest table height 80 0.93 1.21 1.38 24.5 <br /> qh = 15 velocity pressure @ mean roof 90 0.96 1.24 1.40 25.3 <br /> roof pitch = 5 rise 100 0.99 1.26 1.43 26.1 <br /> 12 run q = 22.62 deg <br /> Main Wind Force Resisting System - Part 1 All Heights <br /> Figure 27.4-1 (cont'd)I External Pressure Coefficients, Cp Walls & Roofs <br /> Enclosed, Partially Enclosed Buildings <br /> Wall Pressure Coefficients, Cp <br /> Surface L/B Cp Use With <br /> Windward Wall All Values 0.8 qz <br /> 0-1 -0.5 <br /> Leeward Wall 2 -0.3 qh <br /> >=4 -0.2 <br /> Side Wall All Values -0.7 qh <br /> Roof Pressure Coefficients, Cp, for use with qh <br /> Wind Windward Leeward <br /> Direction Angle, q (degrees) Angle, q (deg.) <br /> h/L 10 15 20 25 30 35 45 >60 10 15 >20 <br /> -0.70 -0.50 -0.30 -0.20 -0.20 0.00 <br /> < .25 -0.30 -0.50 -0.60 <br /> Normal to -0.18 0.00 0.20 0.30 0.30 0.40 0.40 0.23 <br /> ridge for q 0.5 -0.90 -0.70 -0.40 -0.30 -0.20 -0.20 0.00 0.50 -0.50 -0.60 <br /> >10 deg 0.18 -0.18 0.00 0.20 0.20 0.30 0.40 0.23 <br /> > 1.0 -1.30' -1.00 -0.70 -0.50 -0.30 -0.20 0.00 0.70 -0.60 -0.60 <br /> -0.18 -0.18 -0.18 0.00 0.20 0.20 0.30 0.23 <br /> Horizontal distance Value provided for <br /> Normal to from windward edge p interpolation <br /> ridge for q 0 to h/2 -0.90 -0.18 Value can be reduced <br /> <10 deg <.5 h/2 to h -0.90 -0.18 linearly as follows <br /> and h to 2h -0.50 -0.18 Area (sq ft) Reduction <br /> Parallel to > 2h -0.30 -0.18 < 100 1 <br /> ridge for <br /> all q >1.0 0 to h/2 0.18 250 0.9 <br /> > h/2 -0.70 -0.18 > 1000 0.8 <br /> Project: W4371 Sheet No: 25 9/5/2017 <br />