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SáustriEs- <br /> Towers and Poles <br /> BIIIIIIIIIIIIILIIMIMMMIMIIMIIMIIIIIMIIIIMIIIMIIMIIIIMIIIMIMI <br /> December 14, 2016 <br /> Ms. Andrea Gassner <br /> SBA Network Services Inc. <br /> 8051 Congress Avenue <br /> Boca Raton, FL 33487 <br /> RE: 100' (extendible to 150') Sabre Monopole for Stoughton SW, WI <br /> Dear Ms. Gassner, <br /> Upon receipt of order, we propose to design and supply the above referenced Sabre monopole for <br /> a Basic Wind Speed of 90 mph with no ice and 40 mph with 3/4" radial ice, Structure Class II, <br /> Exposure Category C and Topographic Category 1 in accordance with the Telecommunications <br /> Industry Association Standard ANSUTIA-222-G, "Structural Standard for Antenna Supporting <br /> Structures and Antennas". <br /> When designed according to this standard, the wind pressures and steel strength capacities include <br /> several safety factors, resulting in an overall minimum safety factor of 25%. Therefore, it is highly <br /> unlikely that the monopole will fail structurally in a wind event where the design wind speed is <br /> exceeded within the range of the built-in safety factors. <br /> Should the wind speed increase beyond the capacity of the built-in safety factors, to the point of <br /> failure of one or more structural elements, the most likely location of the failure would be within the <br /> monopole shaft, above the base plate. Assuming that the wind pressure profile is similar to that used <br /> to design the monopole, the monopole will buckle at the location of the highest combined stress ratio <br /> within the monopole shaft. This is likely to result in the portion of the monopole above leaning over <br /> and remaining in a permanently deformed condition. Please note that this letter only applies to <br /> the above referenced monopole designed and manufactured by Sabre Towers & Poles. The <br /> fall radius for the monopole design described above is less than 55 feet. <br /> Sincerely, ` ' ' <br /> M <br /> ' y..4S670-006 <br /> a1OL}y.c1 <br /> Robert E. Beacom, P.E., S.E. �'i► It4 .14 <br /> Senior Design Engineer S.,:• ,,—.4*••r'''(10,a \.lo <br /> Sabre Towers and Poles• 7101 Southbridge Drive•P.O.Box 658•Sioux City,IA 51102-0658 <br /> P:712-258-6690 F:712-279-0814 W:www.SabreTowersandPoles.com <br />