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May 19, 2022 <br />Tim Scott <br />PeakNet <br />9887 Fourth Street North, Suite 100 <br />St. Petersburg, FL 33702 <br />RE: Proposed 230’ Monopole + 5’ lightning rod (235’ total) for Concord,NC <br />(Sabre proposal # 22-5821-JDS) <br />Dear Mr. Scott, <br />Upon receipt of order, we propose to design and supply the above-referenced monopole for a <br />Basic Wind Speed of 110 mph without ice and 30 mph with 1.5” ice, Structure Classification II, <br />Exposure Category C, and Topographic Category 1, in accordance with the <br />Telecommunications Industry Association Standard ANSI/TIA-222-G, “Structural Standards for <br />Steel Antenna Towers and Antenna-Supporting Structures”, to support (3) carriers with <br />industry-standard loads for antennas, lines, and associated equipment. <br />When designed according to this standard, the wind pressures and steel strength capacities <br />include several safety factors, resulting in an overall minimum safety factor of 25%. Therefore, <br />it is highly unlikely that the monopole will fail structurally in a wind event where the design wind <br />speed is 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 <br />of failure of one or more structural elements, the most likely location of the failure would be <br />within the monopole shaft, above the base plate. Assuming that the wind pressure profile is <br />similar to that used to design the monopole, the monopole will buckle at the location of the <br />highest combined stress ratio within the monopole shaft. This is likely to result in the portion of <br />the monopole above leaning over and remaining in a permanently deformed condition. This <br />would effectively result in a fall radius of 90’. Please note that this letter only applies to the <br />above-referenced monopole designed and manufactured by Sabre Industries. <br />Sincerely, <br />David Hill, P.E. <br />Design Engineer II <br />Sabre Industries, Inc. • 7101 Southbridge Drive • Sioux City, IA 51111 <br />P: 712-258-6690 F: 712-279-0814 W: www.SabreIndustries.com <br /> <br />